Kessler K10: Scoring and Interpretation Guide
A scoring and interpretation guide to the Kessler Psychological Distress Scale (K10): what it measures, its response format and scoring, the widely used Australian severity bands, psychometric background, and how to use it for screening and outcome monitoring. The items themselves are not reproduced.
About this resource
The K10 was developed by Ronald Kessler and Daniel Mroczek for the US National Health Interview Survey and published with its validation by Kessler and colleagues in 2002. It is a 10-item self-report measure of non-specific psychological distress over the past 30 days, asking how often the person has experienced symptoms of anxiety and depression such as nervousness, hopelessness, restlessness, fatigue, low mood and worthlessness. Each item is rated on a five-point frequency scale, giving a total of 10 to 50. A six-item short form, the K6, uses a subset of the items.
The scale was designed for population surveys, where it is used to estimate the prevalence of probable mental disorder, and it has since become a routine measure in primary care, community mental health and psychological therapy services, particularly in Australia and Canada. Because it measures general distress rather than a specific disorder, it is useful as a first screen and as an outcome measure across mixed presentations, and it is often paired with disorder-specific scales such as the PHQ-9 and GAD-7 when a more precise picture is needed.
This guide covers the structure, scoring, severity bands, psychometric background, use in session, limitations and how to obtain the instrument. The items are not reproduced here; the K10 is copyrighted by its authors, although it is freely available for use and can be obtained from the official sources named at the end. The professional version adds the scoring bands with their source and guidance on the difference between survey and clinical uses.
How to use it
- Obtain the official version of the K10 and give it at assessment, asking the client to rate each item for the past 30 days (some versions say the past four weeks).
- Score each item from 1 (none of the time) to 5 (all of the time) and sum for a total between 10 and 50. Check the version you are using: a few adaptations score items 0 to 4, giving a range of 0 to 40, and the bands below do not apply to those.
- Interpret the total using the Australian bands (10 to 19 likely to be well, 20 to 24 mild, 25 to 29 moderate, 30 to 50 severe distress) and follow up any score of 20 or more with a clinical assessment.
- Repeat at intervals during treatment and at discharge to track change. The 30-day time frame means monthly repetition is the natural rhythm.
- Pair the K10 with disorder-specific measures and direct questions about risk, because it does not identify which disorder is present and contains no suicide item.
References
- Kessler, R. C., Andrews, G., Colpe, L. J., Hiripi, E., Mroczek, D. K., Normand, S.-L. T., Walters, E. E., & Zaslavsky, A. M. (2002). Short screening scales to monitor population prevalences and trends in non-specific psychological distress. Psychological Medicine, 32(6), 959-976.
- Andrews, G., & Slade, T. (2001). Interpreting scores on the Kessler Psychological Distress Scale (K10). Australian and New Zealand Journal of Public Health, 25(6), 494-497.
- Kessler, R. C., Barker, P. R., Colpe, L. J., Epstein, J. F., Gfroerer, J. C., Hiripi, E., Howes, M. J., Normand, S.-L. T., Manderscheid, R. W., Walters, E. E., & Zaslavsky, A. M. (2003). Screening for serious mental illness in the general population. Archives of General Psychiatry, 60(2), 184-189.
