Purpose: A Prescription Event Monitoring (PEM) study was carried out by the Drug Safety Research Unit (DSRU) to monitor the safety of irbesartan, an angiotensin II antagonist, immediately after launch in the United Kingdom in September 1997. The DSRU 'green form' questionnaire response rate was lower than expected. The manufacturer was conducting a concurrent postmarketing surveillance study. The aim of this cross-sectional study, was to identify reasons for non-response by general practitioners in England.
Methods: In PEM, questionnaires are posted to the prescribing general practitioner approximately 6 months after the date of the first prescription for each patient, requesting details of clinical events recorded in the patients' notes since starting treatment. Those that failed to respond were sent a second questionnaire, including tick box questions to elucidate reasons for non-response.
Results: A total of 21.3% (3088/14502) second send forms were returned. There were 1747 tick box responses. The most common reason specified for non-response was 'I was too busy' (31.2%) followed by 'no payment included' (13.4%). Participation in another study accounted for only 3.4%.
Conclusions: The concurrent postmarketing surveillance study was not a significant factor. The general practitioner's workload appeared to have a far larger impact. While research remains a non-core activity and receives no payment, participation is likely to fall. Researchers need to find means of benefiting the general practitioner if participation is to continue.