Aims: Voluntary adverse drug reaction (ADR) reporting schemes have operated since the early sixties in many Western countries. It is generally recognized, however, that only a small proportion of ADRs is actually reported. The current survey was conducted to assess attitudes towards reporting of ADRs, and to study which types of ADRs are reported.
Methods: A questionnaire seeking reasons for nonreporting was sent to a random sample of 10% of medical practitioners in The Netherlands in October 1997. After 6 weeks, a reminder was sent to those who had not responded.
Results: One thousand four hundred and forty-two (73%) questionnaires were returned, of which 94% were complete. The percentage of GPs (51%) which had ever reported an ADR to the national reporting centre was significantly higher than the percentage of specialists (35%), who reported more often to the pharmaceutical industry (34% vs 48%). 86% of GPs, 72% of surgical specialists and 81% of medical specialists had ever diagnosed an ADR, which they had not reported. Uncertainty as to whether the reaction was caused by a drug (72%), the ADR being trivial (75%) or too well known (93%) were the most important reasons for not reporting. 18% were not aware of the need to report ADRs, 22% did not know how to report ADRs, 38% did not have enough time, 36% thought that reporting was too bureaucratic and only 26% of Dutch physicians knew which ADRs to report. A serious ADR, an unlabelled ADR, an ADR to a new drug, history of reporting of one or more ADRs, and specialty were all independently associated with reporting of 16 hypothetical ADRs. Surgical and medical specialists tended to report less often than GPs.
Conclusions: There is a considerable degree of underreporting, which might partly be explained by lack of knowledge and misconceptions about spontaneous reporting of adverse drug reactions.