Hospital discharge diagnoses: how accurate are they and their international classification of diseases (ICD) codes?

The accuracy of the discharge diagnoses recorded in hospital medical records, and the accuracy of their ICD codes, were retrospectively examined in 174 randomly chosen hospital patients. There was a 29% error rate in the recorded ICD codes when compared at a three digit level to the results obtained by retrospectively reviewing the records, establishing diagnoses and coding them. The error rate increased when medical records coders, rather than medically trained personnel, undertook the task of establishing the discharge diagnoses.