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K10 and K6 Scales
The K10 and K6 scales were developed with support from the U.S. government's National Center for Health Statistics for use in the redesigned U.S. National Health Interview Survey (NHIS). As described in more detail in Kessler et al. (2003), the scales were designed to be sensitive around the threshold for the clinically significant range of the distribution of nonspecific distress in an effort to maximize the ability to discriminate cases of serious mental illness (SMI) from non-cases. A small validation study carried out in a convenience sample in Boston found evidence that the scales perform quite well and that, in fact, the six-question scale is at least as sensitive as the ten-question scale for the purpose of discriminating between cases and non-cases of SMI. The K6 is now included in the core of the NHIS as well as in the annual National Household Survey on Drug Abuse. The K10 is in the Australian and Canadian equivalents of the NHIS. The K10 is also included in the National Comorbidity Survey Replication (NCS-R) as well as in all the national surveys in the World Mental Health (WMH) Initiative.

Two versions of the scales are presented here, one for interviewer-administration and the other for self-administration. Note that the K6 is merely a truncated form of the K10 in which four questions are deleted. The question series presented here include not only the six or ten Likert scale questions in the scales, but also a number of other questions that we routinely administer along with the scales to learn about persistence and impairment. These additional questions are not required to score the K6 or K10.

Permission requests

Use of the K6 and K10 is free and does not require any formal permission or approval. We do ask that you please cite the below article and include the copyright when using these scales. In addition, we would appreciate it if you would send us the citations to all final publications that use the K6/K10.

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.

Copyright © Ronald C. Kessler, PhD. All rights reserved.

K6
K10
Self-Administered (English) Self-Administered (English)
Interviewer-administered (English) Interviewer-administered (English)

Scoring rules: click here.

Translated versions of the K6/K10 instruments

The translations of the K6 and K10 are posted for unrestricted use, with the same requirement to acknowledge the copyright and cite the above article.

If you wish to translate K6 and or K10 into a language not listed below (please also check the additional translations posted on the Australian websites), you have permission to do so. We no longer require that you submit the translation for approval but we recommend that you follow one of these guidelines below and cite the protocol that you followed in your publications.

International Test Commission, ITC Guidelines for Translating and Adapting Tests, 2017.

University of Michigan, Cross-cultural Survey Guidelines, Translation. 2020.

Language
K6
K10
Arabic
Chinese (Cantonese)
Not available*
Chinese (Mandarin)
Danish
Not available*
Dutch
Finnish
Download
French
Download
Not available*
German
Not available*
Greek
Download
Not available*
Hebrew
Download
Italian
Japanese
Malay
Not available*
Mongolian
Not available*
Nepali
Not available*
Persian
Not available*
Portuguese (for use in Brazil)
Not available*
Sinhalese
Spanish (for use in Spain)
Spanish (for use in Americas)
Swahili
Not available*
Download
Swedish
Tagalog
Not available*
Turkish
Urdu
Vietnamese
Not available*
Welsh
Not available*

*Not yet translated in this language.

Additional translations are available on these websites below.

http://www.dhi.health.nsw.gov.au/Transcultural-Mental-Health-Centre/Resources/Translations-/Kessler10/Kessler10/default.aspx.

http://http://www.healthtranslations.vic.gov.au/bhcv2/bhcht.nsf/PresentDetail?Open&s=Kessler_10_(K10)_Assessment_Form.

Methodology papers

Puac-Polanco, V., Ziobrowski, H.N., Zainal, N.H., Sampson, N.A., Kessler, R.C. (2025). K10 and K6 Scales. In: Krägeloh, C.U., Alyami, M., Medvedev, O.N. (Eds.) International Handbook of Behavioral Health Assessment (pp. 1-30). Cham, Switzerland: Springer Cham.

Furukawa, T.A., Kessler, R.C., Slade, T., Andrews, G. (2003). The performance of the K6 and K10 screening scales for psychological distress in the Australian National Survey of Mental Health and Well-Being Psychological Medicine. 33:357-362.

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

Kessler, R.C., Andrews, G., Colpe, L.J., Hiripi, E., Mroczek, D.K., Normand, S.-L.T., Walters, E.E., & Zaslavsky, A. (2002). Short screening scales to monitor population prevalances and trends in nonspecific psychological distress. Psychological Medicine. 32(6), 959-976.

Green, J.G., Gruber, M.J., Sampson, N.A., Zaslavsky, A.M., Kessler, R.C. (2010). Improving the K6 short scale to predict serious emotional disturbance in adolescents in the USA. International Journal of Methods in Psychiatric Research 19(S1), 23-35.

Kessler, R.C., Green, J.G., Gruber, M.J., Sampson, N.A., Bromet, E., Cuitan, M., Furukawa, T.A., Gureje, O., Hinkov, H., Hu, C.Y., Lara, C., Lee, S., Mneimneh, Z., Myer, L., Oakley-Browne, M., Posada-Villa, J., Sagar, R., Viana, M.C., Zaslavsky, A.M. (2010). Screening for serious mental illness in the general population with the K6 screening scale: results from the WHO World Mental Health (WMH) survey initiative. International Journal of Methods in Psychiatric Research 19(S1), 4-22. Erratum in International Journal of Methods in Psychiatric Research 2011 Mar;20(1):62.

Additional papers on studies that used K6 and K10 are listed here: View here

Frequently Asked Questions

Q. We note that asking clients about the 'last 4 weeks' may prevent us from identifying change in distress over the course of a brief intervention (i.e. 4-6 weeks). Will it cause significant issues when interpreting scores if we changed the wording to 'in the last 7 days' for each item?

Changing the wording to 'in the last 7 days' is ok and should not cause significant issues in interpreting scores.

Q. Have you ever used the CDC measure of "frequent mental distress (FMD)" derived from the question "Thinking about your mental health, for how many days during the past 30 days was your mental health not good?" in the same survey where K-6 questions are used? If yes, to which extent may FMD and psychological distress overlay? Do they measure different things?

The FMD question has a much more skewed distribution than the K6 or K10 and should only be used when you are interested in fleshing out the top 1-2% of the population. The K6 is best to use when you want to look at serious mental illness (about 5-8% of the population). The K6 was not designed to distinguish the top 1-2% from the rest of the population. If you want to have sensitivity throughout the severity range, you can use the K6 or K10 along with the FMD question. Remember, though, that in order to have adequate statistical power for substantive analysis of the top 1-2% of the population, you need a very large sample.

Q: A question has been raised by several colleagues about the likelihood of seriously ill persons who are being successfully treated (manic depressives with lithium, for example) being picked up by the K6. How do we handle this problem?

A: Symptom screening scales miss people who are successfully treated. It takes much more extensive instruments to find people who have, say, bipolar disorder, but who are being successfully treated. A quick thing you might want to do if you want to know this stuff in a rough and ready way: You can ask people if they are in treatment and, if so, you can ask them to think about the month before treatment and to tell you how they would respond to the K10/K6 questions for that month. Note that this approach will only expand your assessment to include people who might have high distress right now were it not for current treatment (e.g., taking their lithium every day). You will not pick up people with a history of SMI who are currently doing well without treatment.