[Adoption of new medications by prescribing physicians. The innovator physician]

To determine how new medicines are adopted by primary care doctors, identifying innovators or first adopters. Also, to define the variables determining the characteristics of innovative doctors.

Retrospective, longitudinal, observational and descriptive study.

Primary care doctors from the Bahía-Vejer Area in Cádiz (78 general practitioners and 22 paediatricians).

All the prescriptions dispensed in pharmacy offices between 1/1/94 and 31/12/96 and prescribed by doctors with over three years experience (74 doctors) were analysed. The active principles sold for the first time between 1/10/93 and 31/12/96 and mainly used in primary care were chosen. Medicines coming on prescription were grouped by three-month periods (28 medicines) and studied for a year. The number of containers of each group prescribed by each doctor was calculated. The doctors were classified in decreasing order according to the number of containers used and given scores through weighting more the initial periods of the prescription of each medicine. The characteristics of the innovative doctor were found with the following variables: age, gender, training, type of care network, type of contract, drugs expenditure and prescription quality through logistic regression. The OR of prevalence for each variable analysed was calculated, and 90% confidence intervals were also determined. 33% of the total (25 doctors) were identified as innovative doctors or first adopters. The statistically significant variables correlating with this group of doctors were: doctors aged > 45, male, non-MIR training, temporary contract, not their sole job, with drug expenditure over the area's 50 percentile, from non-reformed centres.

The identification of this group of doctors will enable specific programmes to be set up in an attempt to alter their attitude to the marketing of new medicines (objective information, evaluation comparing new medicines with existing ones, and increasing doctors' awareness of perceived risk of the use of medicines).