Comparison of the GHQ-36, the GHQ-12 and the SCL-90 as psychiatric screening instruments in the Finnish population

Abstract

The aim of the study was to compare the screening properties of two General Health Questionnaire (GHQ) versions and the Symptom Checklist (SCL-90), and to evaluate them as psychiatric screening instruments in Finland. We administered the GHQ-36 and the SCL-90 to psychiatric outpatients (n=207) and to a community sample (n=315). Receiver operating characteristic (ROC) analysis was used to estimate the screening performance of the two instruments and of the GHQ-12 extracted from the GHQ-36. The screening properties of the scales were found to be good and similar. Suggested optimal cut-off points were 3/4 for the GHQ-12, 8/9 for the GHQ-36 and 0.90/0.91 for the SCL-90. In conclusion, the scales functioned equally well in screening. This favors the GHQ-12 for pure screening. When information on the symptom level is also needed, the GHQ-36 and the SCL-90 become better choices. The cut-off points presented here should be considered in the future Finnish psychiatric screening studies.