Self-report stability for substance use over 10 years: data from the St. Louis Epidemiologic Catchment Study.

In substance abuse research many study protocols require the recall and report of behavior from the distant past that may affect reliability. This study addresses the stability of substance use reports over a 10-year follow-up period. We reinterviewed 223 ECA subjects who reported baseline drug use. Reports from baseline to follow-up were categorized as either incident cases, agreements, or discrepancies. Different patterns were found for each substance group. The authors found that cannabis, cocaine, sedatives, and opiates had high agreement rates ranging from 82-86% and amphetamines had the lowest (73%). Implications for future drug research are discussed.