STABILITY OF DIAGNOSIS OF OBSESSIVE-COMPULSIVE DISORDER IN THE EPIDEMIOLOGIC CATCHMENT-AREA STUDY

Objective: This study examined the 2-year temporal stability of a Nati onal Institute of Mental Health Diagnostic Interview Schedule (DIS) li fetime diagnosis of obsessive-compulsive disorder in the Epidemiologic Catchment Area (ECA) study. Method: In that study 20,862 individual, aged 18 years and over, at five sites were evaluated by lay interviewe rs using the DIS (wave 1). All of those who were available 12 months l ater were reinterviewed (wave 2). In the present study, the temporal s tability of wave 1 obsessive-compulsive disorder diagnoses at wave 2 w as examined, as well as relationships with comorbid diagnoses. The con sistency of reports of ''new-onset'' illness was also examined. Factor s contributing to these measures were evaluated. Results: The temporal stability of the diagnosis of obsessive-compulsive disorder order was very low. Subjects with a stable diagnosis of obsessive-compulsive di sorder had a higher rate of both obsessions and compulsions, an earlie r age at onset, and more comorbid anxiety, affective, and alcohol abus e/dependence disorders at initial assessment. The originally reported 1-year incidence estimates for obsessive-compulsive disorder primarily reflect data from subjects at wave 2 who reported the onset of sympto ms as preceding the wave 1 interview. Older and less-educated subjects had significantly higher error rates in reporting onset. Conclusions: The DIS diagnosis of obsessive-compulsive disorder has poor validity, leaving the true incidence and prevalence of the disorder unknown. Ol der and less-educated subjets require special attention in the design of instruments for use with community samples.