The Performance of the K6 Scale in a Large School Sample

Timely prevalence data of psychiatric morbidity among adolescents in small areas remains vital for mental health policy planning at the regional and local levels. Furthermore, effective regional policy planning also requires the measurement of psychiatric morbidity using clinically validated instruments. The K6 scale was therefore included on the 2012 administration of the Kentucky Incentives for Prevention Survey as a measure of serious emotional disturbance in the past 30 days. Principal axis and confirmatory factor analyses were performed to determine the unidimensional structure of the K6 in a school-based sample of Kentucky students (n = 108,736). The documented cutoff of 13 on the K6 was then used to screen Kentucky students for serious emotional disturbance, estimate the state prevalence, and define epidemiologic correlates. Overall, the K6 performed well, with factor analyses confirming the 1-factor solution of the K6. Based upon the established cutoff, the prevalence of serious emotional disturbance was 13.9% in Kentucky. Grade, gender, race and ethnicity, and family structure emerged as significant predictors in a multivariable logistic regression model. Substance abuse, antisocial behavior, role impairments, and peer victimization were significantly higher among students with a positive screen. These results indicate the K6 is particularly useful for inclusion in large epidemiologic surveys that have limited space and logistics that demand timely administration.