The Kessler PSychological Distress Scale in Te Rau Hinengaro: The New Zealand Mental Health Survey:

Objective: The aim of the present study was to compare two versions of the Kessler 10-item scale (K10), as measures of population mental health status in New Zealand.Method: A nationwide household survey of residents aged ≥16 years was carried out between 2003 and 2004. The World Mental Health Composite International Diagnostic Interview (CIDI 3.0) was used to obtain DSM-IV diagnoses. Serious mental illness (SMI) was defined as for the World Mental Health Surveys Initiative and the USA National Comorbidity Survey Replication. Participants were randomly assigned to receive the ‘past month’ K10 or the ‘worst month in the past 12 months’ K10. There were 12 992 completed interviews; 7435 included the K10. The overall response rate was 73.3%. Receiver operator characteristic (ROC) curves were used to examine the ability of both K10 versions to discriminate between CIDI 3.0 cases and non-cases, and to predict SMI.Results: Scores on both versions of the K10 were higher for female subjects, younger people, people...