RATIONALE, AIMS AND OBJECTIVES: Although demand for medication is regarded as one of the most important factors in pharmaceutical expenditure, little is known about patients' influence on drug prescribing. This study assesses the influence exerted on drug prescribing by patients' attitudes and expectations, and by doctors' perception of such expectations.

METHOD

We conducted a population-based cohort study covering 937 subjects attending a health centre in the northwest of Spain. Prescription-drug advertising directly targeted at patients is banned in Spain. We conducted home-based interviews at the start of follow-up to assess patients' attitudes, and monthly telephone interviews during the 1-year follow-up period to assess consumption of medical drugs and medical visits. Using nested case-control study covering 127 of the cohort subjects who attended the health centre, we assessed patients' pre-consultation expectations for prescriptions, doctors' perception of such patients' expectations, and the drugs actually prescribed.

RESULTS

Of the total sample, 69.3% answered the home-based questionnaire, 77.6% completed 11 or more months of follow-up, and 100% of cohort subjects who attended the health centre responded to the pre-consultation survey conducted in the waiting room. Patients' attitudes, though not associated with prescription (P > 0.1), were, however, associated with demand for medical consultation (P < 0.01), self-medication (P < 0.01) and prescription expectations (P < 0.01). Although doctors' perception of patients' expectations did indeed show an association with drug prescribing (P = 0.001), there was no association between patients' expectations and doctors' perception of such expectations (P > 0.1), as these tended to be overestimated by doctors.

CONCLUSION

We conclude that, although doctors prescribe in accordance with what they believe their patients expect, in practice patients exert no influence on drug prescribing because their prescription expectations are misconstrued by doctors, who overestimate them.