Amish Study, II: Consensus diagnoses and reliability results

Reliability of diagnosis is central to genetic research on mental illness. In the Amish Study of affective disorders, consensus diagnoses were derived by a psychiatric board using the Research Diagnostic Criteria (RDC). To verify the reliability of diagnoses, the authors 1) studied how well board members followed RDC procedures, 2) compared diagnoses based on abstracted medical records with those based on full medical records, 3) compared diagnoses based on the two data sources-- abstracted medical records and the Schedule for Affective Disorders and Schizophrenia-Lifetime Version--and 4) studied diagnostic stability to determine validity of diagnosis. The results of these substudies demonstrate a high concordance of diagnosis.