In this study of self-reported physician behavior, avoiding cost to the patient was the most consistent motivator for physicians to use drug samples, although physicians acknowledged other benefits of drug samples that varied with the clinical scenarios. The perceived benefits of drug samples often led physicians to report that they would dispense or prescribe drugs that differed from their preferred drug choice. Residents and internists were more likely to report using drug sample than attendings and family physicians.
Physicians' self-reported drug sample use appears to be driven by the best intentions of providing high-quality care to patients. In the treatment of a lower, uncomplicated UTI, drug samples served as a source of immediate drug therapy, allowing physicians to initiate treatment promptly to relieve the patient's symptoms and prevent potential complications. In comparison, for the management of depression in which responses and side effects to drug therapy vary, drug samples were used on a trial basis to assess individual effectiveness and side effects.
Physicians' self-reported drug sample dispensing suggests that the availability of drug samples may alter their prescribing practices, with potential implications for patient care and health care costs. The most disturbing finding is that the presence of drug samples may influence physicians to dispense or prescribe drugs that differ from their preferred drug choice. As a result, it is possible that compliance with evidence-based guidelines may be decreased. For example, all surveyed clinic sites had adopted the JNC V guidelines, which are based on scientific evidence related to long-term efficacy and cost for the treatment of HTN.14,15
The preferred drug in the HTN scenario for almost all respondents was a β-blocker or diuretic, consistent with JNC V recommendations. But when drug samples were made available, 27% of physicians indicated that they would dispense a drug sample not recommended as a first-line agent by JNC V.14,15
It is particularly noteworthy that in reducing the burden of drug costs on an individual patient, physicians may actually increase the overall cost of prescription medications. This is apparent in the HTN scenario, where a significant proportion of self-reported sample users subsequently would write a prescription for the more expensive sampled medication (which also differed from their preferred drug choice). Therefore, despite short-term cost savings to the patient, overall societal costs could increase when the sampled drug was subsequently prescribed although patients would not necessarily incur the additional costs. In addition, given the higher rate of sample use by residents, drug sample availability may influence resident behavior potentially leading to increased costs and suboptimal prescribing patterns over the long run.
Several features of this study may limit the generalizability of our findings. The study was conducted in an academic center, and we presented only a few case scenarios with limited treatment choices. Therefore, our results may not be generalizable to other clinical settings or other disease processes. In using a scenario-based questionnaire, we were limited in our ability to simulate actual clinic visits and patient-provider relationships and have no direct confirmation of reported behavioral changes associated with drug samples. Previous research has documented variability in the extent to which written case simulations reflect actual clinical practice.17,18
Response and social desirability biases may have inflated rates of compliance with guidelines and underestimated use of nonpreferred drugs.
This is the first study to our knowledge that addresses when and why physicians use drug samples, and under what circumstances physicians will subsequently prescribe a medication that was initially dispensed as a drug sample. By targeting a physician population based at one institution that has a formulary and clinical guidelines in common, we were able to minimize potential variability related to institutional policy. The anonymity of the survey encouraged accurate reporting of behavior and our high response rate minimized nonresponse bias. Given the lack of available data in this area, we hope this use of clinical vignettes will provide the impetus and guidance for future research that can assess actual practice patterns in diverse clinical settings.
Professional groups may want to develop guidelines similar to the Society of Teachers of Family Medicine guidelines10
with protocols encouraging the appropriate use of drug samples. In addition, techniques such as academic detailing of unbiased drug information by health care professionals may be an effective means to promote the selection of drugs based on efficacy and cost.19
Most importantly, because prescribing habits develop during training, increased attention and educational efforts should be directed at minimizing the effects of drug sample availability on residents' prescribing practices. Residents should be educated about the clinical use of drug samples and teaching clinics should consider alternative means of providing medications to patients who cannot afford to buy them. It is incumbent upon the medical profession to ensure that drug sample availability does not lead to overutilization of expensive medications when effective and inexpensive alternatives are available.
Local and national policy changes could counteract potential adverse effects of drug sample availability on physicians' practice patterns. Some health care organizations and training programs may want to consider developing alternatives to drug samples. One option is the availability of prepacks of first-line medications in clinics allowing physicians to initiate therapy immediately and save patients a trip to the pharmacy without changing physicians' drug choices to expensive second-line medications. Alternatively, the development of patient-assistance programs to provide indigent patients with medications at lower or no cost could lessen the burden of drug costs to those patients without the use of drug samples. If drug samples are used for patient care, we must ensure that they are used appropriately and without adversely affecting subsequent prescribing behavior or inflating long-term costs.