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How Does Physician Advice Influence Patient Behavior?

How Does Physician Advice Influence Patient Behavior? ObjectiveTo explore a potential "priming effect" of physician advice on patient responses to behavioral change interventions.DesignRandomized controlled trial with a 3-month follow-up.SettingFour community-based group family medicine clinics in southeastern Missouri.ParticipantsAdult patients (N=915).InterventionsPrinted educational materials designed to encourage patients to quit smoking, eat less fat, and increase physical activity.Main Outcome MeasuresRecall, rating, and use of the educational materials; changes in smoking behavior, dietary fat consumption, and physical activity.ResultsPatients who received physician advice to quit smoking, eat less fat, or get more exercise prior to receiving intervention materials on the same topic were more likely to remember the materials, show them to others, and perceive the materials as applying to them specifically. They were also more likely to report trying to quit smoking (odds ratio [OR&rsqb;=1.54, 95% confidence interval [CI&rsqb;=0.95-2.40), quitting for at least 24 hours (OR=1.85, 95% CI=1.02-3.34), and making some changes in diet (OR=1.35, 95% CI=1.00-1.84) and physical activity (OR=1.51, 95% CI=0.95-2.40).ConclusionsFindings support an integrated model of disease prevention in which physician advice is a catalyst for change and is supported by a coordinated system of information and activities that can provide the depth of detail and individualization necessary for sustained behavioral change.NATIONAL DISEASE prevention objectivesand practice guidelinescall for physicians to advise patients more routinely to modify health-related behaviors like tobacco use, physical inactivity, and eating unhealthy diets. Underlying these recommendations are 4 basic assumptions: (1) certain behaviors can lead to increased risk for many chronic diseases, (2) effective strategies exist to help patients make behavioral changes, (3) making such changes can reduce a person's disease risk, and (4) patients who receive physician advice are often more likely to successfully enact behavioral changes. A large and growing body of epidemiologic evidence and intervention evaluations support the first 3 assumptions.However, the nature of the physician advice–patient behavior relationship is less well understood.Although physician counseling interventions have been shown to help patients quit smoking,evidence for the efficacy of counseling patients to modify their diets and level of physical activity is minimal.Among studies reporting favorable results in any of these areas, physician counseling is almost always combined with other intervention strategies, and often involves repeated advice, follow-up visits, and referral.While more intensive, multifaceted counseling interventions may be the ideal, they are not always feasible in many primary care settings. Furthermore, owing to the way these studies have been designed, it is often difficult to disentangle the effect of physician counseling from that of other intervention approaches that were used concurrently. As a result, we cannot be certain that the relationship between physician counseling and patient behavior change is a causal one. More importantly, little is known about the specific mechanisms through which physician counseling might work. By better understanding the nature of this relationship, physician counseling could potentially be made more effective and less demanding. To maximize the effectiveness of physician advice and justify its continued inclusion in population-based disease prevention guidelines, a more thorough understanding of this relationship is necessary.Basic models of communication suggest that for patient education materials or other health-related information to stimulate attitude or behavior change, certain intermediary steps like paying attention to the materials and understanding their content must also occur.Some educational materials are more likely to have these effects than others. For example, the elaboration likelihood model of Petty and Caciopposuggests people will process information more thoughtfully and carefully if they perceive it to be personally relevant. Messages processed in this way (ie, "elaborated" on) tend to be retained for a longer period of time and are more likely to lead to permanent change.One possible mechanism for a behavioral change effect of physician counseling can be inferred from these theoretical frameworks; that advice from a physician to make lifestyle changes may "prime" patients to become more aware of and attentive to health information, programs, and services they may encounter as a result of either planned intervention or happenstance. In addition, patients whose physician has recommended that they modify some behavior may subsequently view information about that behavior as more personally relevant. This explanation is also consistent with theories of health-related behavior change. For example, the health belief model suggests that persons who perceive themselves to be susceptible to some adverse health outcome can sometimes be prompted to take precautions by a simple cue to action such as physician advice.The transtheoretical model or "stages of change" theory also suggests that patients who are thinking about adopting lifestyle changes (ie, "contemplators") may be motivated to take action by relatively minimal interventions.If physician advice indeed has such a priming effect, the implications for practice are clear. Disease prevention programs should attempt to engineer this synergy, assuring that physicians' advice is fully coordinated with adjunctive materials, programs, or services available for all patients.This longitudinal study sought to identify differences in the ways patients respond to printed behavior change materials based on whether their primary care physician had previously advised them to change the same behavior. Analyses examine differences in patients' recall of receiving materials, amount of materials read, perceived relevance of materials, saving and sharing materials with others, and actual behavior change.PARTICIPANTS AND METHODSSTUDY POPULATIONThe study population was composed of 915 adult patients (aged ≥18 years) drawn by convenience sample from 4 community-based family medicine clinics in southeastern Missouri. This region was selected because it has the highest rates of cardiovascular disease in the state and lower than average rates of preventive counseling by physicians.Rates of poverty and unemployment in the region are also higher than state averages.The 4 sites were selected based on their comparatively high patient volume for the region. After reading and signing the approved consent form, patients enrolled in the study by completing a self-administered questionnaire in the waiting area of their physician's office. Thirty-three of the 915 patients who returned questionnaires were disqualified owing to extensive missing data, leaving a final baseline sample of 882 patients. The questionnaire and all aspects of the study were approved by the institutional review board of St Louis University, St Louis, Mo.BASELINE QUESTIONNAIRE AND MEASURESThe self-administered baseline questionnaire included multi-item assessments of cigarette smoking, physical activity, dietary fat consumption, and patients' receipt of physician advice on selected lifestyle behaviors. Smoking status was measured by asking whether the patient had smoked a cigarette, even a puff, in the last 7 days. Level of physical activity was assessed by asking patients to report the number of days per week they had participated for at least 30 minutes in 8 different categories of physical activity. Each category included examples of specific activities that required at least moderate energy expenditure (>3 metabolic equivalents)and were consistent with recent national recommendations.Responses to the categories of "sports," "strengthening exercises," "dancing," and "aerobic-type exercise" were summed to calculate a total score on leisure time physical activities. Responses to the categories of "child care," "work in the home," "home repair," and "yard work" were summed to calculate a score for physical activities of daily living. Dietary fat intake was assessed using a 15-item screen developed by Block et al.This instrument yields a total fat score ranging from 0 to 60, with scores of 22 and higher indicating a need for reduced dietary fat intake. Its scores have been shown to correlate reasonably well (0.65) with multiple dietary records.We divided the total fat score into 3 categories: meat sources (6 items), dairy sources (5 items), and fried sources (4 items). Stage of readiness was also assessed for each of the 3 behaviors by asking patients which of 4 statements best described them (don't want to change, seriously thinking about changing in the next 6 months, planning to change in the next 30 days, or already trying to change). Physician advice was measured by asking patients to identify their usual physisican from a list and indicate whether in the last 6 months that physician had told them to quit smoking, get more physical activity, or eat less fat in their diet. Patients could also indicate that they had not seen their physician in the last 6 months. Demographic variables were also assessed. Baseline questionnaires were distributed and collected by members of each medical office staff, who were paid $1 at the end of the study for each completed questionnaire. Baseline data were collected during March 1996, with data collection periods ranging from 8 to 12 days by practice.HEALTH EDUCATION MATERIALSData reported in this study were drawn from a larger investigation undertaken to determine the relative efficacy of 3 different types of printed health education materials in helping patients reduce behavioral risk factors for cardiovascular disease. In the larger study, patients who completed the baseline questionnaire were randomly assigned to receive computer-generated educational materials that were either tailored to their specific needs and concerns, generic but personalized using the patient's name, or generic but not personalized, or to a usual-care control group receiving no educational materials. Educational materials were mailed to the homes of intervention group patients within 2 to 4 days of completing the baseline questionnaire. In this mailing, a short cover letter from the physician's office and project staff thanked patients for completing the questionnaire and introduced the educational materials.All 3 types of educational materials included text and graphics in a 3-column format and were printed on identical letter-size paper with the project name ("Change of Heart") and logo in color at the top of the page. Two single-sided pages of information were generated for each of the 3 behavioral risk factors (ie, smoking, physical inactivity, high level of dietary fat consumption). Current smokers in all 3 intervention groups received educational materials on quitting smoking, regardless of their stage of readiness to quit. Patients free of contraindications to exercise as measured by the Physical Activity Readiness Questionnaireand who were in the contemplation, preparation, or action/maintenance stages of readiness to increase physical activityreceived educational materials on exercise. Patients with a total fat score of 22 or higher on the food frequency assessment, regardless of their stage of readiness to make dietary changes, received educational materials on dietary fat consumption. Information on reducing dietary fat consumption through increased nutrition label reading was also given if patients reported drinking any kind of milk on a regular basis. Patients could receive educational materials for 0, 1, 2, or all 3 behaviors based on these eligibility criteria.FOLLOW-UP AND ATTRITIONFollow-up questionnaires were mailed to patients' homes 3 months after baseline data collection. After 2 weeks, nonrespondents were sent a second follow-up questionnaire in the mail. Patients who did not respond to either questionnaire were contacted by telephone and asked to complete the questionnaire in a telephone interview with a trained research assistant. The follow-up questionnaire was the same as that administered at baseline except its time-based questions referred only to the study period (ie, "In the last 3 months . . .?"). Questions were also added to assess patients' recall, rating, and use of the intervention materials they had received. Patients were first asked if they remembered receiving any health information in the mail from the study. Those who answered yes were then asked how much, if any, of the information they read (all of it, most of it, some of it, none of it); how well the information applied to them (didn't apply at all, could have applied to anyone, applied to me specifically); whether they still had the information they received (yes, no); and whether they had shown the information to any friends or family members (yes, no).Seventy-eight percent of patients (685/882) completed a follow-up assessment. Of these 685, 51% returned the first questionnaire, 18% returned the second, and 31% completed a telephone interview. Although respondents tended to be older and were more likely to be women compared with nonrespondents, this pattern did not vary by study group. Among nonrespondents, 47% indicated by mail or telephone they were not interested in participating in follow-up, 18% were never reached because their telephone number had been disconnected or they had moved with no forwarding address, and the remainder never responded to either mail or telephone follow-up.STATISTICAL ANALYSESThe outcomes of primary interest in the study were patients' recall, rating, and use of the educational materials they received, and changes in smoking behavior, dietary fat consumption, and physical activity. For each of these outcomes, analyses compared proportional change across 2 groups of patients: (1) those who reported at baseline receiving physician advice to change the same behavior for which they received educational materials in the study; and (2) those who reported at baseline that their physician provided no advice, or reported receiving advice to change a behavior for which they did not receive educational materials in the study.Logistic regression analyses were conducted to test for group differences. Dependent variables included patient recall (remembered receiving materials/didn't remember), reading (read all or most of the materials/read some or none), perceived relevance (materials applied to me specifically/could have applied to anyone or didn't apply to me at all), keeping (kept the materials/didn't keep them), sharing (shared the materials with friends or family members/didn't share), and behavior change (modified smoking, physical activity, or diet behaviors/didn't change behavior). In all analyses, one dependent variable was regressed on a dichotomous independent variable for physician advice (reported receiving advice/reported not receiving advice), a control variable for type of educational materials received (tailored/personalized/generic), and 4 control variables known to be associated with receiving physician advice or preventive services: patient's ageand years of education(both scaled as continuous variables), and sexand income(scaled as a dichotomous variable, ≤$30,000/>$30,000). Because educational materials for smoking cessation and dietary fat consumption were provided to patients who were in different stages of readiness to change those behaviors, analyses of these outcomes also adjusted for patients' behavior-specific stage of readiness to change.The purpose of these analyses was to determine the effect of physician advice on patients' use of printed educational materials. Accordingly, only patients who actually received educational materials were included. Analyses of patients' recall, rating, and use of educational materials compared 2 groups of patients: (1) those who had received physician advice to change some behavior and subsequently received educational materials addressing the same behavior; and (2) those for whom no such match existed. Analyses of behavioral outcomes compared similar groups, although the denominator varied across the 3 behaviors. For example, a given patient may have been advised by his or her physician to quit smoking, but not to eat less fat. Yet in this study the patient met the criteria to receive educational materials on both topics. As a result, he or she would be counted in the "matched" group denominator for analyses of smoking outcomes, but in the "unmatched" group denominator for analyses of dietary fat consumption.Although the purpose of the study was not to evaluate the relative contribution of physician advice and educational materials to patients' behavioral change, the study design allows for a preliminary examination of this question. Evidence for a direct effect of physician advice (vs the hypothesized synergistic effect) would largely negate the "priming" explanation put forth in this article. To consider this possibility, we compared in post hoc analyses the rates of behavior change among control group patients (who were randomly assigned to receive no educational materials) who did and did not report having received physician advice. In these analyses, differences that were similar in direction and magnitude to findings from the main analyses would constitute evidence for a potential direct effect of physician advice. In other words, if the same results are found regardless of whether a patient received educational materials, it is probably physician advice alone, not its synergy with educational materials, that is driving observed differences. On the other hand, if receipt or nonreceipt of physician advice is not associated with behavioral change among control group patients, the priming hypothesis cannot be rejected.RESULTSPARTICIPANTSOf the 685 patients who completed a follow-up questionnaire, 519 (76%) had been randomly allocated to 1 of the 3 intervention groups and 496 (96%) of these met the criteria to receive educational materials on either smoking cessation, dietary fat consumption, or physical activity. These 496 patients were predominantly women (76%) and white (98%), with a mean age of 49 years. Roughly two thirds of patients (69%) had 12 or fewer years of education, and 59% reported a 1996 pretax household income of $30,000 or less. A total of 27 physicians from the 4 clinics had at least 1 of their patients enrolled in the study. All but 1 physician was male, and all were white.RECEIVING PHYSICIAN ADVICE AND EDUCATIONAL MATERIALSIn all, 44% of patients (219/496) reported that their physician had told them to change at least 1 of the 3 health-related behaviors considered in the study. About half of smokers (52%) reported receiving advice to quit, 25% of patients reported receiving advice to eat less fat, and 24% reported receiving advice to get more exercise. All 101 smokers were sent educational materials on cessation, 486 patients (98%) were sent materials on reducing dietary fat consumption, and 153 patients (31%) were sent materials on increasing physical activity. Among patients who were sent materials on dietary fat consumption, 25% reported that their physician had told them to eat less fat. Among patients who received materials on physical activity, 18% reported that their physician had told them to get more exercise.RECALL AND USE OF EDUCATIONAL MATERIALSAt 3-month follow-up, most patients said they remembered receiving educational materials from the study, but there were no overall differences in recall between those who had received matching physician advice and those who had not (63% vs 57%). However, among women patients, those who had received matching physician advice were about 30% more likely to remember receiving educational materials than those who did not receive advice (70% vs 60%; odds ratio [OR&rsqb;=1.29, 95% confidence interval [CI&rsqb;=1.01-1.66). Patients who received matching physician advice were also more likely to show the educational materials to a friend or family member (51% vs 34%; OR=1.48, 95% CI=1.13-1.95) and to report that the materials applied to them specifically (44% vs 31%; OR=1.30, 95% CI=0.98-1.72). However, there were no significant differences across the 2 groups in the proportion of patients who reported reading most or all of the materials (76% vs 71%) or keeping the materials (65% vs 58%). Findings are reported for all patients and by patients' sex in Table 1.Table 1. Reaction to Mailed Health Education Materials Among Patients Who Did and Did Not Receive Physician Advice to Change the Same Behavior Addressed by the MaterialsPatient CharacteristicPercentageUnadjusted Odds Ratio (95% Confidence Interval)Adjusted Odds Ratio† (95% Confidence Interval)Physician Advice*No Physician AdviceRemembered receiving health education materialsAll (N=458)63571.13 (0.93-1.38)1.21 (0.98-1.49)Women (n=351)70601.23 (0.97-1.56)1.29 (1.01-1.66)Men (n=107)45460.98 (0.66-1.45)0.96 (0.63-1.47)Showed health education materials to a friendAll (N=256)51341.42 (1.10-1.84)1.48 (1.13-1.95)Women (n=208)47281.49 (1.11-2.00)1.57 (1.15-2.14)Men (n=48)67571.24 (0.67-2.27)1.08 (0.52-2.21)Said health education materials applied to themAll (N=247)44311.32 (1.01-1.72)1.30 (0.98-1.72)Women (n=202)44311.32 (0.98-1.77)1.31 (0.96-1.79)Men (n=45)41291.32 (0.70-2.49)1.03 (0.45-2.34)Read all or most of health education materialsAll (N=254)76711.13 (0.84-1.51)1.09 (0.80-1.47)Women (n=206)79741.17 (0.83-1.64)1.19 (0.84-1.69)Men (n=48)61601.02 (0.56-1.86)1.51 (0.70-3.27)Kept health education materials they receivedAll (N=254)65581.14 (0.87-1.48)1.09 (0.83-1.43)Women (n=206)67601.17 (0.87-1.57)1.11 (0.82-1.51)Men (n=48)56531.05 (0.58-1.88)1.10 (0.58-2.08)*Includes patients who reported receiving physician advice about the same topic for which they were sent educational materials in the study.†Analyses of women and men adjusted for study group, patient's age, years of education, annual household income; analyses of both combined also adjusted for sex.BEHAVIOR CHANGEAmong patients who received educational materials to help them stop smoking, those who reported their physician had told them to quit were 54% more likely to have tried to quit during the study period than were those whose physicians provided no such advice (49% vs 24%; OR=1.54, 95% CI=0.95-2.51). Those who received physician advice to quit were also more likely to quit smoking for at least 24 hours (35% vs 13%; OR=1.85, 95% CI=1.02-3.34), but were no more likely to report 7-day continuous abstinence at follow-up (4% vs 9%). Patients who received educational materials on physical activity and reported that their physician had told them to get more exercise were more likely to have increased leisure time activities at follow-up (64% vs 48%; OR=1.51, 95% CI=0.95-2.40) but less likely to have increased physical activities of daily living (25% vs 36%) compared with patients who did not receive physician advice. Among patients who received educational materials to help them eat less fat, those who did and did not receive physician advice had almost identical rates of reducing dietary fat from meat sources (33% vs 33%) and fried foods (37% vs 36%). However, those who received physician advice to eat less fat were 35% more likely to reduce fat from dairy sources at follow-up (47% vs 33%; OR=1.35, 95% CI=1.00-1.84). Table 2summarizes these behavioral findings.Table 2. Behavioral Changes Among Patients Who Did and Did Not Receive Physician Advice to Change the Same Behavior Addressed by the Health Education Materials They ReceivedBehavioral ChangePercentageUnadjusted Odds Ratio (95% Confidence Interval)Adjusted Odds Ratio† (95% Confidence Interval)Physician Advice*No Physician AdviceSmoking cessation, % of smoking patients whoTried to quit smoking (n=91)49241.75 (1.12-2.75)1.54 (0.95-2.51)Quit for at least 24 h (n=89)35131.93 (1.11-3.35)1.85 (1.02-3.34)Had quit at follow-up (n=97)490.65 (0.27-1.57)0.52 (0.19-1.41)Physical activity, % of inactive patients whoIncreased leisure time activities‡ (n=134)64481.39 (0.91-2.14)1.51 (0.95-2.40)Increased physical activities of daily living§ (n=146)25360.76 (0.48-1.22)0.73 (0.45-1.18)Dietary fat intake, % of patients eating high-fat diets whoWere eating less meat fat (n=321)33331.02 (0.77-1.35)1.06 (0.79-1.41)Were eating less dairy fat (n=280)47331.36 (1.01-1.83)1.35 (1.00-1.84)Were eating less fried fat (n=329)37361.02 (0.78-1.34)1.06 (0.80-1.40)*Includes patients who reported receiving physician advice about the same topic for which they were sent educational materials in the study.†Adjusted for study group, patient's age, sex, years of education, and household income; smoking and diet analyses also adjust for stage of readiness to change.‡Includes aerobic-type exercise, strengthening exercises, sports, and dancing.§Includes work around the home, child care, yard work, and home repair.POST HOC ANALYSESAmong smokers in the control group, those who received physician advice to quit were actually somewhat less likely to have tried to quit during the study period than were those who did not receive such advice (20% vs 56%; P<.08, n=24). Likewise, control group smokers who reported receiving physician advice to quit were no more likely to quit for at least 24 hours (40% vs 33%) than those who did not report such advice. Rates of 7-day continuous abstinence at follow-up were not significantly different (6% vs 18%) from those found among intervention group patients. Among control group patients who would have received educational materials on physical activity, there were no differences among patients who did and did not report receiving physician advice in the proportion who increased leisure time activities (33% vs 33%; n=39) or physical activities of daily living (33% vs 35%; n=46). Among control group patients who would have received educational materials on dietary fat consumption, the pattern of differences between those who did and did not report having received physician advice is nearly identical to that reported in Table 2for fat from meat sources (30% vs 30%; n=99), dairy products (53% vs 29%; P<.05), and fried foods (35% vs 35%).COMMENTThis study sought to better understand a possible mechanism by which physician advice influences patient behaviors. In the study, patients who reported having received physician advice to quit smoking, eat less fat, or get more exercise prior to being sent printed educational materials on the same topic were more likely to remember the materials, show them to a friend or family member, and perceive the materials as applying to them specifically, compared with patients who received the same materials but did not report having received physician advice. According to theories of communication and information processing, intermediate outcomes like these (ie, recall, interest, and perceived relevance) can be important precursors to behavior change.These findings suggest that receiving physician advice may make patients (women in particular) more attuned to other information they encounter that is consistent with their physician's recommendations. In addition, patients who reported having received physician advice to quit smoking prior to receiving educational materials about quitting were more likely to make a quit attempt and to quit for at least 24 hours compared with patients who received the materials but did not report receiving physician advice. Similar differences were found for patients increasing their leisure time physical activity and eating less fat from dairy products, although no differences were found for patients increasing physical activities of daily living or fat intake from meats or fried foods. The inconsistent findings in the areas of physical activity and diet may simply reflect a relatively low awareness among patients and physicians of new recommendations for physical activities of daily living, and the relative ease of change in dairy fat consumption compared with other dietary changes. Given the convenience nature of the sample and characteristics of the patients (ie, mostly white) and physicians (ie, mostly male and all white) in the study, generalizing these findings to other primary care populations would be inappropriate.Post hoc control group analyses found no greater success in quitting smoking or increasing physical activity among patients who reported having received physician advice compared with patients who reported receiving no such advice. Because such positive differences did exist in the main analyses, these data are consistent with a priming effect of physician advice. On the other hand, the pattern and magnitude of effects for dietary change in control group patients who did and did not report having received physician advice is nearly identical to that observed among patients who received educational materials on dietary fat consumption. This could be viewed as evidence that the educational materials on dietary fat consumption were relatively inert, suggesting a possible direct effect of physician advising. Because of the exploratory and preliminary nature of these analyses and the equivocal findings they produce, we cannot definitively confirm or refute the priming hypothesis.In 1996, the US Preventive Services Task Force recognized as a research priority the need for "determining the effectiveness of counseling interventions, especially ones that are feasible in primary care settings."(pxxvi) To explore this relationship, it is first necessary to distinguish between physician counseling and physician advice. Although the 2 terms are frequently used interchangeably,physician counseling suggests a more interactive and in-depth encounter, while physician advice may involve making only a brief recommendation to adopt or modify a behavior. In this study, we asked patients if their physician had told them to get more physical activity, eat less fat in their diet, or quit smoking. Clearly, it requires less of a physician's time and little special training to tell a patient he or she needs to make a change, as opposed to showing them how to change or taking specific steps to help them change. While the more intensive counseling approach may be ideal, it is not always feasible given physicians' limited time and training in behavior modification.However, because physician advice offers less substantive guidance than counseling would, it is important to closely link advising activities with other materials or resources that provide that guidance. Viewed from this perspective, the findings implicitly support an integrated model of disease prevention in which physician advice is only the catalyst for change and is supported by a coordinated system of activities that can provide the depth of detail and individualization that is necessary for sustained behavioral change. Translating these findings into practice would require physicians to provide patients with a strong recommendation to change, followed by additional information, resources, or services coordinated to reinforce that recommendation. Identification and distribution of these ancillary educational materials should be integrated into the health care provider system.Advocating for the use of written materials and other interventions together with counseling is nothing new.Educational materials addressing preventive health behaviors are often available for patients through their physicians' offices. However, the use of the materials on a consistent basis and in a coordinated fashion together with physician advice occurs less often. This study suggests that establishing a link between written materials and physician advice would be an important first step in establishing an office-based system for disease prevention. At the simplest level, this may mean better coordination of existing resources such as the preprinted brochures and pamphlets often available in the waiting room of physicians offices. However, referring patients to poorly designed materials will not likely have the desired effect. A better approach would be to coordinate physician advising with office-based, computer-generated educational information that is tailored to the specific needs of individual patients. Tailored health education materials include any combination of strategies and information intended to reach one specific patient, based on characteristics that are unique to that patient, related to the outcome of interest, and derived from an individual assessment.In a series of randomized trials, tailored materials have been shown to be more effective than usual primary care or "one size fits all" preprinted materials in helping some primary care patients change a range of health-related behaviors.This study relied on patients' reports of receiving physician advice. Although it is possible that these reports do not accurately reflect whether advice was actually given, patient reports seem to provide a more conservative estimate of this important variable. For example, several recent studies have found that physicians may overreport their own prevention activities.In this study, using a method published previously,we evaluated levels of agreement between physician and patient reports of advising and found them to be low: 61% for eating less fat and 58% for increasing physical activity. The majority of nonagreeing cases (88%) involved physicians reporting they advised patients and patients reporting they were not advised. It could be that recall of physician advice is itself related to some unmeasured patient characteristic or patient-physician interaction dynamic that also influences the processing of health information and the modification of health-related behaviors. Analyses in this study adjusted for patients' age, sex, education, income, and behavior-specific stage of readiness to change. Although it is unclear to us what such an additional characteristic might be, it is still possible that one could exist.Successful disease prevention programs in primary care settings will systematically detect patients who need preventive services, advise them that preventive action is needed, and use automated data systems to support and reinforce physician advice and preventive services.Physician advice that primes patients to act on subsequent health information will play an important role in this disease prevention equation.Department of Health and Human ServicesHealthy People 2000: National Health Promotion and Disease Prevention Objectives.Washington, DC: Dept of Health and Human Services; 1991. DHHS publication PHS 91-50212.Preventive Task ForceGuide to Clinical Preventive Services.2nd ed. 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results from a randomized trial.Health Educ Res.1996;11:97-105.DBrinbergMLAxelsonIncreasing consumption of dietary fiber: a decision theory analysis.Health Educ Res.1990;5:409-420.SJCurryDLouieLCGrothausEHWagnerWritten personalized feedback and confidence in smoking cessation.Psychol Addict Behav.1992;6:175-180.JOProchaskaCCDiClementeWFVelicerJSRossiStandardized, individualized, interactive and personalized self-help programs for smoking cessation.Health Psychol.1993;12:399-405.BHMarcusBCBockBMPintoLHForsythMBRobertsRMTraficanteEfficacy of an individualized, motivationally tailored physical intervention.Ann Behav Med.In press.CELewisDisease prevention and health promotion practices of primary care physicians in the United States.Am J Prev Med.1988;4:9-16.DEMontañoWRPhillipsCancer screening by primary care physicians: a comparison of rates obtained from physician self-report, patient survey, and chart audit.Am J Public Health.1995;85:795-800.MKKreuterDPScharffLKBrennanSNLukwagoPhysician recommendations for diet and physical activity: which patients get advised to change?Prev Med.1997;26:825-833.RSThompsonSHTaplinTAMcAfeeMRMandelsonAESmithPrimary and secondary prevention services in clinical practice: twenty years' experience in development, implementation, and evaluation.JAMA.1995;273:1130-1135.Accepted for publication April 9, 1999.This project was funded through contract U48/CCU710806 from the Centers for Disease Control and Prevention, Atlanta, Ga (Centers for Research and Demonstration of Health Promotion and Disease Prevention).We thank Darcell Scharff, PhD, for her assistance in reviewing the manuscript.Reprints: Matthew W. Kreuter, PhD, MPH, Health Communication Research Laboratory, School of Public Health, Saint Louis University, 321 N Spring Ave, St Louis, MO 63108 (e-mail: kreuter@slu.edu). http://www.deepdyve.com/assets/images/DeepDyve-Logo-lg.png Archives of Family Medicine American Medical Association

How Does Physician Advice Influence Patient Behavior?

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Abstract

ObjectiveTo explore a potential "priming effect" of physician advice on patient responses to behavioral change interventions.DesignRandomized controlled trial with a 3-month follow-up.SettingFour community-based group family medicine clinics in southeastern Missouri.ParticipantsAdult patients (N=915).InterventionsPrinted educational materials designed to encourage patients to quit smoking, eat less fat, and increase physical activity.Main Outcome MeasuresRecall, rating, and use of the educational materials; changes in smoking behavior, dietary fat consumption, and physical activity.ResultsPatients who received physician advice to quit smoking, eat less fat, or get more exercise prior to receiving intervention materials on the same topic were more likely to remember the materials, show them to others, and perceive the materials as applying to them specifically. They were also more likely to report trying to quit smoking (odds ratio [OR&rsqb;=1.54, 95% confidence interval [CI&rsqb;=0.95-2.40), quitting for at least 24 hours (OR=1.85, 95% CI=1.02-3.34), and making some changes in diet (OR=1.35, 95% CI=1.00-1.84) and physical activity (OR=1.51, 95% CI=0.95-2.40).ConclusionsFindings support an integrated model of disease prevention in which physician advice is a catalyst for change and is supported by a coordinated system of information and activities that can provide the depth of detail and individualization necessary for sustained behavioral change.NATIONAL DISEASE prevention objectivesand practice guidelinescall for physicians to advise patients more routinely to modify health-related behaviors like tobacco use, physical inactivity, and eating unhealthy diets. Underlying these recommendations are 4 basic assumptions: (1) certain behaviors can lead to increased risk for many chronic diseases, (2) effective strategies exist to help patients make behavioral changes, (3) making such changes can reduce a person's disease risk, and (4) patients who receive physician advice are often more likely to successfully enact behavioral changes. A large and growing body of epidemiologic evidence and intervention evaluations support the first 3 assumptions.However, the nature of the physician advice–patient behavior relationship is less well understood.Although physician counseling interventions have been shown to help patients quit smoking,evidence for the efficacy of counseling patients to modify their diets and level of physical activity is minimal.Among studies reporting favorable results in any of these areas, physician counseling is almost always combined with other intervention strategies, and often involves repeated advice, follow-up visits, and referral.While more intensive, multifaceted counseling interventions may be the ideal, they are not always feasible in many primary care settings. Furthermore, owing to the way these studies have been designed, it is often difficult to disentangle the effect of physician counseling from that of other intervention approaches that were used concurrently. As a result, we cannot be certain that the relationship between physician counseling and patient behavior change is a causal one. More importantly, little is known about the specific mechanisms through which physician counseling might work. By better understanding the nature of this relationship, physician counseling could potentially be made more effective and less demanding. To maximize the effectiveness of physician advice and justify its continued inclusion in population-based disease prevention guidelines, a more thorough understanding of this relationship is necessary.Basic models of communication suggest that for patient education materials or other health-related information to stimulate attitude or behavior change, certain intermediary steps like paying attention to the materials and understanding their content must also occur.Some educational materials are more likely to have these effects than others. For example, the elaboration likelihood model of Petty and Caciopposuggests people will process information more thoughtfully and carefully if they perceive it to be personally relevant. Messages processed in this way (ie, "elaborated" on) tend to be retained for a longer period of time and are more likely to lead to permanent change.One possible mechanism for a behavioral change effect of physician counseling can be inferred from these theoretical frameworks; that advice from a physician to make lifestyle changes may "prime" patients to become more aware of and attentive to health information, programs, and services they may encounter as a result of either planned intervention or happenstance. In addition, patients whose physician has recommended that they modify some behavior may subsequently view information about that behavior as more personally relevant. This explanation is also consistent with theories of health-related behavior change. For example, the health belief model suggests that persons who perceive themselves to be susceptible to some adverse health outcome can sometimes be prompted to take precautions by a simple cue to action such as physician advice.The transtheoretical model or "stages of change" theory also suggests that patients who are thinking about adopting lifestyle changes (ie, "contemplators") may be motivated to take action by relatively minimal interventions.If physician advice indeed has such a priming effect, the implications for practice are clear. Disease prevention programs should attempt to engineer this synergy, assuring that physicians' advice is fully coordinated with adjunctive materials, programs, or services available for all patients.This longitudinal study sought to identify differences in the ways patients respond to printed behavior change materials based on whether their primary care physician had previously advised them to change the same behavior. Analyses examine differences in patients' recall of receiving materials, amount of materials read, perceived relevance of materials, saving and sharing materials with others, and actual behavior change.PARTICIPANTS AND METHODSSTUDY POPULATIONThe study population was composed of 915 adult patients (aged ≥18 years) drawn by convenience sample from 4 community-based family medicine clinics in southeastern Missouri. This region was selected because it has the highest rates of cardiovascular disease in the state and lower than average rates of preventive counseling by physicians.Rates of poverty and unemployment in the region are also higher than state averages.The 4 sites were selected based on their comparatively high patient volume for the region. After reading and signing the approved consent form, patients enrolled in the study by completing a self-administered questionnaire in the waiting area of their physician's office. Thirty-three of the 915 patients who returned questionnaires were disqualified owing to extensive missing data, leaving a final baseline sample of 882 patients. The questionnaire and all aspects of the study were approved by the institutional review board of St Louis University, St Louis, Mo.BASELINE QUESTIONNAIRE AND MEASURESThe self-administered baseline questionnaire included multi-item assessments of cigarette smoking, physical activity, dietary fat consumption, and patients' receipt of physician advice on selected lifestyle behaviors. Smoking status was measured by asking whether the patient had smoked a cigarette, even a puff, in the last 7 days. Level of physical activity was assessed by asking patients to report the number of days per week they had participated for at least 30 minutes in 8 different categories of physical activity. Each category included examples of specific activities that required at least moderate energy expenditure (>3 metabolic equivalents)and were consistent with recent national recommendations.Responses to the categories of "sports," "strengthening exercises," "dancing," and "aerobic-type exercise" were summed to calculate a total score on leisure time physical activities. Responses to the categories of "child care," "work in the home," "home repair," and "yard work" were summed to calculate a score for physical activities of daily living. Dietary fat intake was assessed using a 15-item screen developed by Block et al.This instrument yields a total fat score ranging from 0 to 60, with scores of 22 and higher indicating a need for reduced dietary fat intake. Its scores have been shown to correlate reasonably well (0.65) with multiple dietary records.We divided the total fat score into 3 categories: meat sources (6 items), dairy sources (5 items), and fried sources (4 items). Stage of readiness was also assessed for each of the 3 behaviors by asking patients which of 4 statements best described them (don't want to change, seriously thinking about changing in the next 6 months, planning to change in the next 30 days, or already trying to change). Physician advice was measured by asking patients to identify their usual physisican from a list and indicate whether in the last 6 months that physician had told them to quit smoking, get more physical activity, or eat less fat in their diet. Patients could also indicate that they had not seen their physician in the last 6 months. Demographic variables were also assessed. Baseline questionnaires were distributed and collected by members of each medical office staff, who were paid $1 at the end of the study for each completed questionnaire. Baseline data were collected during March 1996, with data collection periods ranging from 8 to 12 days by practice.HEALTH EDUCATION MATERIALSData reported in this study were drawn from a larger investigation undertaken to determine the relative efficacy of 3 different types of printed health education materials in helping patients reduce behavioral risk factors for cardiovascular disease. In the larger study, patients who completed the baseline questionnaire were randomly assigned to receive computer-generated educational materials that were either tailored to their specific needs and concerns, generic but personalized using the patient's name, or generic but not personalized, or to a usual-care control group receiving no educational materials. Educational materials were mailed to the homes of intervention group patients within 2 to 4 days of completing the baseline questionnaire. In this mailing, a short cover letter from the physician's office and project staff thanked patients for completing the questionnaire and introduced the educational materials.All 3 types of educational materials included text and graphics in a 3-column format and were printed on identical letter-size paper with the project name ("Change of Heart") and logo in color at the top of the page. Two single-sided pages of information were generated for each of the 3 behavioral risk factors (ie, smoking, physical inactivity, high level of dietary fat consumption). Current smokers in all 3 intervention groups received educational materials on quitting smoking, regardless of their stage of readiness to quit. Patients free of contraindications to exercise as measured by the Physical Activity Readiness Questionnaireand who were in the contemplation, preparation, or action/maintenance stages of readiness to increase physical activityreceived educational materials on exercise. Patients with a total fat score of 22 or higher on the food frequency assessment, regardless of their stage of readiness to make dietary changes, received educational materials on dietary fat consumption. Information on reducing dietary fat consumption through increased nutrition label reading was also given if patients reported drinking any kind of milk on a regular basis. Patients could receive educational materials for 0, 1, 2, or all 3 behaviors based on these eligibility criteria.FOLLOW-UP AND ATTRITIONFollow-up questionnaires were mailed to patients' homes 3 months after baseline data collection. After 2 weeks, nonrespondents were sent a second follow-up questionnaire in the mail. Patients who did not respond to either questionnaire were contacted by telephone and asked to complete the questionnaire in a telephone interview with a trained research assistant. The follow-up questionnaire was the same as that administered at baseline except its time-based questions referred only to the study period (ie, "In the last 3 months . . .?"). Questions were also added to assess patients' recall, rating, and use of the intervention materials they had received. Patients were first asked if they remembered receiving any health information in the mail from the study. Those who answered yes were then asked how much, if any, of the information they read (all of it, most of it, some of it, none of it); how well the information applied to them (didn't apply at all, could have applied to anyone, applied to me specifically); whether they still had the information they received (yes, no); and whether they had shown the information to any friends or family members (yes, no).Seventy-eight percent of patients (685/882) completed a follow-up assessment. Of these 685, 51% returned the first questionnaire, 18% returned the second, and 31% completed a telephone interview. Although respondents tended to be older and were more likely to be women compared with nonrespondents, this pattern did not vary by study group. Among nonrespondents, 47% indicated by mail or telephone they were not interested in participating in follow-up, 18% were never reached because their telephone number had been disconnected or they had moved with no forwarding address, and the remainder never responded to either mail or telephone follow-up.STATISTICAL ANALYSESThe outcomes of primary interest in the study were patients' recall, rating, and use of the educational materials they received, and changes in smoking behavior, dietary fat consumption, and physical activity. For each of these outcomes, analyses compared proportional change across 2 groups of patients: (1) those who reported at baseline receiving physician advice to change the same behavior for which they received educational materials in the study; and (2) those who reported at baseline that their physician provided no advice, or reported receiving advice to change a behavior for which they did not receive educational materials in the study.Logistic regression analyses were conducted to test for group differences. Dependent variables included patient recall (remembered receiving materials/didn't remember), reading (read all or most of the materials/read some or none), perceived relevance (materials applied to me specifically/could have applied to anyone or didn't apply to me at all), keeping (kept the materials/didn't keep them), sharing (shared the materials with friends or family members/didn't share), and behavior change (modified smoking, physical activity, or diet behaviors/didn't change behavior). In all analyses, one dependent variable was regressed on a dichotomous independent variable for physician advice (reported receiving advice/reported not receiving advice), a control variable for type of educational materials received (tailored/personalized/generic), and 4 control variables known to be associated with receiving physician advice or preventive services: patient's ageand years of education(both scaled as continuous variables), and sexand income(scaled as a dichotomous variable, ≤$30,000/>$30,000). Because educational materials for smoking cessation and dietary fat consumption were provided to patients who were in different stages of readiness to change those behaviors, analyses of these outcomes also adjusted for patients' behavior-specific stage of readiness to change.The purpose of these analyses was to determine the effect of physician advice on patients' use of printed educational materials. Accordingly, only patients who actually received educational materials were included. Analyses of patients' recall, rating, and use of educational materials compared 2 groups of patients: (1) those who had received physician advice to change some behavior and subsequently received educational materials addressing the same behavior; and (2) those for whom no such match existed. Analyses of behavioral outcomes compared similar groups, although the denominator varied across the 3 behaviors. For example, a given patient may have been advised by his or her physician to quit smoking, but not to eat less fat. Yet in this study the patient met the criteria to receive educational materials on both topics. As a result, he or she would be counted in the "matched" group denominator for analyses of smoking outcomes, but in the "unmatched" group denominator for analyses of dietary fat consumption.Although the purpose of the study was not to evaluate the relative contribution of physician advice and educational materials to patients' behavioral change, the study design allows for a preliminary examination of this question. Evidence for a direct effect of physician advice (vs the hypothesized synergistic effect) would largely negate the "priming" explanation put forth in this article. To consider this possibility, we compared in post hoc analyses the rates of behavior change among control group patients (who were randomly assigned to receive no educational materials) who did and did not report having received physician advice. In these analyses, differences that were similar in direction and magnitude to findings from the main analyses would constitute evidence for a potential direct effect of physician advice. In other words, if the same results are found regardless of whether a patient received educational materials, it is probably physician advice alone, not its synergy with educational materials, that is driving observed differences. On the other hand, if receipt or nonreceipt of physician advice is not associated with behavioral change among control group patients, the priming hypothesis cannot be rejected.RESULTSPARTICIPANTSOf the 685 patients who completed a follow-up questionnaire, 519 (76%) had been randomly allocated to 1 of the 3 intervention groups and 496 (96%) of these met the criteria to receive educational materials on either smoking cessation, dietary fat consumption, or physical activity. These 496 patients were predominantly women (76%) and white (98%), with a mean age of 49 years. Roughly two thirds of patients (69%) had 12 or fewer years of education, and 59% reported a 1996 pretax household income of $30,000 or less. A total of 27 physicians from the 4 clinics had at least 1 of their patients enrolled in the study. All but 1 physician was male, and all were white.RECEIVING PHYSICIAN ADVICE AND EDUCATIONAL MATERIALSIn all, 44% of patients (219/496) reported that their physician had told them to change at least 1 of the 3 health-related behaviors considered in the study. About half of smokers (52%) reported receiving advice to quit, 25% of patients reported receiving advice to eat less fat, and 24% reported receiving advice to get more exercise. All 101 smokers were sent educational materials on cessation, 486 patients (98%) were sent materials on reducing dietary fat consumption, and 153 patients (31%) were sent materials on increasing physical activity. Among patients who were sent materials on dietary fat consumption, 25% reported that their physician had told them to eat less fat. Among patients who received materials on physical activity, 18% reported that their physician had told them to get more exercise.RECALL AND USE OF EDUCATIONAL MATERIALSAt 3-month follow-up, most patients said they remembered receiving educational materials from the study, but there were no overall differences in recall between those who had received matching physician advice and those who had not (63% vs 57%). However, among women patients, those who had received matching physician advice were about 30% more likely to remember receiving educational materials than those who did not receive advice (70% vs 60%; odds ratio [OR&rsqb;=1.29, 95% confidence interval [CI&rsqb;=1.01-1.66). Patients who received matching physician advice were also more likely to show the educational materials to a friend or family member (51% vs 34%; OR=1.48, 95% CI=1.13-1.95) and to report that the materials applied to them specifically (44% vs 31%; OR=1.30, 95% CI=0.98-1.72). However, there were no significant differences across the 2 groups in the proportion of patients who reported reading most or all of the materials (76% vs 71%) or keeping the materials (65% vs 58%). Findings are reported for all patients and by patients' sex in Table 1.Table 1. Reaction to Mailed Health Education Materials Among Patients Who Did and Did Not Receive Physician Advice to Change the Same Behavior Addressed by the MaterialsPatient CharacteristicPercentageUnadjusted Odds Ratio (95% Confidence Interval)Adjusted Odds Ratio† (95% Confidence Interval)Physician Advice*No Physician AdviceRemembered receiving health education materialsAll (N=458)63571.13 (0.93-1.38)1.21 (0.98-1.49)Women (n=351)70601.23 (0.97-1.56)1.29 (1.01-1.66)Men (n=107)45460.98 (0.66-1.45)0.96 (0.63-1.47)Showed health education materials to a friendAll (N=256)51341.42 (1.10-1.84)1.48 (1.13-1.95)Women (n=208)47281.49 (1.11-2.00)1.57 (1.15-2.14)Men (n=48)67571.24 (0.67-2.27)1.08 (0.52-2.21)Said health education materials applied to themAll (N=247)44311.32 (1.01-1.72)1.30 (0.98-1.72)Women (n=202)44311.32 (0.98-1.77)1.31 (0.96-1.79)Men (n=45)41291.32 (0.70-2.49)1.03 (0.45-2.34)Read all or most of health education materialsAll (N=254)76711.13 (0.84-1.51)1.09 (0.80-1.47)Women (n=206)79741.17 (0.83-1.64)1.19 (0.84-1.69)Men (n=48)61601.02 (0.56-1.86)1.51 (0.70-3.27)Kept health education materials they receivedAll (N=254)65581.14 (0.87-1.48)1.09 (0.83-1.43)Women (n=206)67601.17 (0.87-1.57)1.11 (0.82-1.51)Men (n=48)56531.05 (0.58-1.88)1.10 (0.58-2.08)*Includes patients who reported receiving physician advice about the same topic for which they were sent educational materials in the study.†Analyses of women and men adjusted for study group, patient's age, years of education, annual household income; analyses of both combined also adjusted for sex.BEHAVIOR CHANGEAmong patients who received educational materials to help them stop smoking, those who reported their physician had told them to quit were 54% more likely to have tried to quit during the study period than were those whose physicians provided no such advice (49% vs 24%; OR=1.54, 95% CI=0.95-2.51). Those who received physician advice to quit were also more likely to quit smoking for at least 24 hours (35% vs 13%; OR=1.85, 95% CI=1.02-3.34), but were no more likely to report 7-day continuous abstinence at follow-up (4% vs 9%). Patients who received educational materials on physical activity and reported that their physician had told them to get more exercise were more likely to have increased leisure time activities at follow-up (64% vs 48%; OR=1.51, 95% CI=0.95-2.40) but less likely to have increased physical activities of daily living (25% vs 36%) compared with patients who did not receive physician advice. Among patients who received educational materials to help them eat less fat, those who did and did not receive physician advice had almost identical rates of reducing dietary fat from meat sources (33% vs 33%) and fried foods (37% vs 36%). However, those who received physician advice to eat less fat were 35% more likely to reduce fat from dairy sources at follow-up (47% vs 33%; OR=1.35, 95% CI=1.00-1.84). Table 2summarizes these behavioral findings.Table 2. Behavioral Changes Among Patients Who Did and Did Not Receive Physician Advice to Change the Same Behavior Addressed by the Health Education Materials They ReceivedBehavioral ChangePercentageUnadjusted Odds Ratio (95% Confidence Interval)Adjusted Odds Ratio† (95% Confidence Interval)Physician Advice*No Physician AdviceSmoking cessation, % of smoking patients whoTried to quit smoking (n=91)49241.75 (1.12-2.75)1.54 (0.95-2.51)Quit for at least 24 h (n=89)35131.93 (1.11-3.35)1.85 (1.02-3.34)Had quit at follow-up (n=97)490.65 (0.27-1.57)0.52 (0.19-1.41)Physical activity, % of inactive patients whoIncreased leisure time activities‡ (n=134)64481.39 (0.91-2.14)1.51 (0.95-2.40)Increased physical activities of daily living§ (n=146)25360.76 (0.48-1.22)0.73 (0.45-1.18)Dietary fat intake, % of patients eating high-fat diets whoWere eating less meat fat (n=321)33331.02 (0.77-1.35)1.06 (0.79-1.41)Were eating less dairy fat (n=280)47331.36 (1.01-1.83)1.35 (1.00-1.84)Were eating less fried fat (n=329)37361.02 (0.78-1.34)1.06 (0.80-1.40)*Includes patients who reported receiving physician advice about the same topic for which they were sent educational materials in the study.†Adjusted for study group, patient's age, sex, years of education, and household income; smoking and diet analyses also adjust for stage of readiness to change.‡Includes aerobic-type exercise, strengthening exercises, sports, and dancing.§Includes work around the home, child care, yard work, and home repair.POST HOC ANALYSESAmong smokers in the control group, those who received physician advice to quit were actually somewhat less likely to have tried to quit during the study period than were those who did not receive such advice (20% vs 56%; P<.08, n=24). Likewise, control group smokers who reported receiving physician advice to quit were no more likely to quit for at least 24 hours (40% vs 33%) than those who did not report such advice. Rates of 7-day continuous abstinence at follow-up were not significantly different (6% vs 18%) from those found among intervention group patients. Among control group patients who would have received educational materials on physical activity, there were no differences among patients who did and did not report receiving physician advice in the proportion who increased leisure time activities (33% vs 33%; n=39) or physical activities of daily living (33% vs 35%; n=46). Among control group patients who would have received educational materials on dietary fat consumption, the pattern of differences between those who did and did not report having received physician advice is nearly identical to that reported in Table 2for fat from meat sources (30% vs 30%; n=99), dairy products (53% vs 29%; P<.05), and fried foods (35% vs 35%).COMMENTThis study sought to better understand a possible mechanism by which physician advice influences patient behaviors. In the study, patients who reported having received physician advice to quit smoking, eat less fat, or get more exercise prior to being sent printed educational materials on the same topic were more likely to remember the materials, show them to a friend or family member, and perceive the materials as applying to them specifically, compared with patients who received the same materials but did not report having received physician advice. According to theories of communication and information processing, intermediate outcomes like these (ie, recall, interest, and perceived relevance) can be important precursors to behavior change.These findings suggest that receiving physician advice may make patients (women in particular) more attuned to other information they encounter that is consistent with their physician's recommendations. In addition, patients who reported having received physician advice to quit smoking prior to receiving educational materials about quitting were more likely to make a quit attempt and to quit for at least 24 hours compared with patients who received the materials but did not report receiving physician advice. Similar differences were found for patients increasing their leisure time physical activity and eating less fat from dairy products, although no differences were found for patients increasing physical activities of daily living or fat intake from meats or fried foods. The inconsistent findings in the areas of physical activity and diet may simply reflect a relatively low awareness among patients and physicians of new recommendations for physical activities of daily living, and the relative ease of change in dairy fat consumption compared with other dietary changes. Given the convenience nature of the sample and characteristics of the patients (ie, mostly white) and physicians (ie, mostly male and all white) in the study, generalizing these findings to other primary care populations would be inappropriate.Post hoc control group analyses found no greater success in quitting smoking or increasing physical activity among patients who reported having received physician advice compared with patients who reported receiving no such advice. Because such positive differences did exist in the main analyses, these data are consistent with a priming effect of physician advice. On the other hand, the pattern and magnitude of effects for dietary change in control group patients who did and did not report having received physician advice is nearly identical to that observed among patients who received educational materials on dietary fat consumption. This could be viewed as evidence that the educational materials on dietary fat consumption were relatively inert, suggesting a possible direct effect of physician advising. Because of the exploratory and preliminary nature of these analyses and the equivocal findings they produce, we cannot definitively confirm or refute the priming hypothesis.In 1996, the US Preventive Services Task Force recognized as a research priority the need for "determining the effectiveness of counseling interventions, especially ones that are feasible in primary care settings."(pxxvi) To explore this relationship, it is first necessary to distinguish between physician counseling and physician advice. Although the 2 terms are frequently used interchangeably,physician counseling suggests a more interactive and in-depth encounter, while physician advice may involve making only a brief recommendation to adopt or modify a behavior. In this study, we asked patients if their physician had told them to get more physical activity, eat less fat in their diet, or quit smoking. Clearly, it requires less of a physician's time and little special training to tell a patient he or she needs to make a change, as opposed to showing them how to change or taking specific steps to help them change. While the more intensive counseling approach may be ideal, it is not always feasible given physicians' limited time and training in behavior modification.However, because physician advice offers less substantive guidance than counseling would, it is important to closely link advising activities with other materials or resources that provide that guidance. Viewed from this perspective, the findings implicitly support an integrated model of disease prevention in which physician advice is only the catalyst for change and is supported by a coordinated system of activities that can provide the depth of detail and individualization that is necessary for sustained behavioral change. Translating these findings into practice would require physicians to provide patients with a strong recommendation to change, followed by additional information, resources, or services coordinated to reinforce that recommendation. Identification and distribution of these ancillary educational materials should be integrated into the health care provider system.Advocating for the use of written materials and other interventions together with counseling is nothing new.Educational materials addressing preventive health behaviors are often available for patients through their physicians' offices. However, the use of the materials on a consistent basis and in a coordinated fashion together with physician advice occurs less often. This study suggests that establishing a link between written materials and physician advice would be an important first step in establishing an office-based system for disease prevention. At the simplest level, this may mean better coordination of existing resources such as the preprinted brochures and pamphlets often available in the waiting room of physicians offices. However, referring patients to poorly designed materials will not likely have the desired effect. A better approach would be to coordinate physician advising with office-based, computer-generated educational information that is tailored to the specific needs of individual patients. Tailored health education materials include any combination of strategies and information intended to reach one specific patient, based on characteristics that are unique to that patient, related to the outcome of interest, and derived from an individual assessment.In a series of randomized trials, tailored materials have been shown to be more effective than usual primary care or "one size fits all" preprinted materials in helping some primary care patients change a range of health-related behaviors.This study relied on patients' reports of receiving physician advice. Although it is possible that these reports do not accurately reflect whether advice was actually given, patient reports seem to provide a more conservative estimate of this important variable. For example, several recent studies have found that physicians may overreport their own prevention activities.In this study, using a method published previously,we evaluated levels of agreement between physician and patient reports of advising and found them to be low: 61% for eating less fat and 58% for increasing physical activity. The majority of nonagreeing cases (88%) involved physicians reporting they advised patients and patients reporting they were not advised. It could be that recall of physician advice is itself related to some unmeasured patient characteristic or patient-physician interaction dynamic that also influences the processing of health information and the modification of health-related behaviors. Analyses in this study adjusted for patients' age, sex, education, income, and behavior-specific stage of readiness to change. 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Journal

Archives of Family Medicine – American Medical Association

Published: May 1, 2000

References

  • Healthy People 2000: National Health Promotion and Disease Prevention Objectives.
  • Guide to Clinical Preventive Services.
  • Physical Activity and Health: A Report of the Surgeon General.
  • The Surgeon General's Report on Nutrition and Health.
  • Reducing the Health Consequences of Smoking: 25 Years of Progress.
  • Cigarette smoking: attributable mortality and years of potential life lost—United States, 1990.
  • The Health Benefits of Smoking Cessation: A Report of the Surgeon General.
  • Mortality rates after 10.5 years for participation in the Multiple Risk Factor Intervention Trial: findings related to a priori hypotheses of the trial.