Improved detection of depression in primary care through severity evaluation

Objectives: To determine whether the use of a symptom severity measure to augment an existing Diagnostic and Statistical Manual of Mental Disorders - Third Edition, Revised (DSM-III-R) criteria-based depression screener (PRIME-MD) would decrease the difficulties associated with depression screening in primary care by filtering out patients with minimal impairment. STUDY DESIGN: The study design was secondary data analysis. POPULATION: The study sample comprised 1317 patients, with intentional oversampling by ethnicity and sex, presenting for routine care at a university family practice center in Galveston, Texas. OUTCOMES MEASURED: The primary outcomes were cross-sectional, health-related quality-of-life outcomes of subjects who met symptom severity criteria as well as criteria for a DSM-III-R mood disorder. Health care utilization outcomes were examined as secondary outcomes. RESULTS: The combination of a 6-item depression severity instrument and the PRIME-MD resulted in 71% of depressed subjects being categorized as severely symptomatic and 29% as minimally symptomatic. Severely symptomatic subjects had significantly worse SF-36 Mental Health Component Summary scale (MCS) scores than did minimally symptomatic subjects (32.8 vs 43.5, P < .05). Minimally symptomatic subjects had MCS scores similar to those of a third group of subjects who did not meet DSM-III-R "threshold" criteria for mood disorder but who were severely symptomatic. Adjusted health care utilization was higher for the initial 3-month charge period in the severely symptomatic depressed subjects compared with minimally symptomatic depressed subjects ($679.20 vs $462.38, P < .05). CONCLUSIONS: The 6-item depression severity measure effectively separated patients meeting DSM-III-R "threshold" depression criteria into 2 groups: one presenting with severe symptoms and impairment and the other presenting with mild symptoms and significantly less impairment. A strategy of initial screening using a brief depression severity instrument, followed with a DSM criteria-based instrument, could decrease the immediate clinician workload by one third and focus treatment on those most likely to benefit.