Adverse drug reactions in patients admitted to hospital identified by discharge ICD-10 codes and by spontaneous reports

Aims We studied the international classification of disease (ICD) hospital discharge codes to find unreported adverse drug reactions (ADRs), and asked doctors about their attitudes to reporting some of these cases. Methods We examined the ICD codes assigned on discharge to identify ADRs an d compared these with spontaneous reports made to the Committee on Safety o f Medicines (CSM). Doctors involved were sent brief resumes of cases and as ked if they would report them. Results 49 of 21 365 patient episodes were coded on discharge as ADRs, of w hich 33 were 'reportable'. Fourteen spontaneous reports were received by th e CSM during the same period. The two groups did not overlap. 25 of 60 doct ors responded to our questionnaire, and would have reported only 8 of 75 ca ses outlined. Conclusions The ICD coding allowed us to identify important ADRs which most doctors would not report spontaneously.