Concurrent Validity of Depression Diagnoses Versus Continuous Syndrome Depression Scores

Abstract

Using a sample of depressed adults taken from the NIMH Treatment for Depression Collaborative Research Program (TDCRP), I examined the concurrent and incremental validity of using depression diagnoses, diagnostic components, and continuous syndrome depression scores to predict theoretically-relevant dependent variables. This study builds upon previous work in this area because (a) a variety of conceptually and theoretically relevant categorical and continuous dependent variables were studied, (b) it evaluated the non-symptom criteria required to meet the diagnostic threshold, and (c) the same measures were used to derive both the diagnoses and the continuous symptom scores, thus eliminating the confounding effects of the content versus structure of measures for which most previous studies have failed to control. The findings from this study suggest that depression diagnoses, key symptom criteria (i.e., sadness and/ or anhedonia), and duration criteria add relatively little predictive utility over and above continuous syndrome measures of depression.