Mental Health Test (K10)

Ronald Kessler and his colleagues built the K10 for the redesigned US National Health Interview Survey. They tried out candidate questions in a national mail survey and a national telephone survey, then used item response theory to choose ten. Six of those ten make up a shorter form, the K6. The paper came out in Psychological Medicine in 2002.

The K6 went into the 1997 and 1998 US National Health Interview Surveys, and the K10 into Australia's 1997 national mental health survey. The authors also list US and Canadian government health surveys and the WHO World Mental Health Surveys among its uses.

The questions here come from the self-administered English form on Kessler's page. That form opens with "During that month, how often did you feel" and lists the ten feelings under it. We repeat the words "How often did you feel" on each line, so a question still makes sense once you've scrolled past the top. Kessler's page says use of the scale "is free and does not require any formal permission or approval." It asks for a citation of the 2003 paper and this line: Copyright © Ronald C. Kessler, PhD. All rights reserved.

The 2002 paper reports good precision in the 90th to 99th percentile range of the population, the range where serious distress shows up. Both scales worked consistently across major sociodemographic groups and separated people with and without DSM-IV disorders, checked against structured clinical interviews.

A 2003 study in Archives of General Psychiatry gave the K10 and K6 to an enriched convenience sample of 155 people, then did a clinical interview about the past 12 months. It looked for serious mental illness, meaning a DSM-IV disorder other than a substance use disorder plus marked trouble functioning. The area under the ROC curve was 0.854 for the K10 and 0.865 for the K6, where 1 would be perfect separation and 0.5 a coin flip. The K6 had a sensitivity of 0.36 and a specificity of 0.96, so it rarely flagged people without serious illness and missed many who had it.

In 2001, Andrews and Slade compared K10 scores with symptoms, disability, service use and diagnosis in the Australian National Survey of Mental Health and Well-Being. They found the K10 related to those measures in predictable ways.

Kessler's scoring notes give each answer 0 to 4, for a total of 0 to 40, and say Australia uses 1 to 5, for 10 to 50. This page uses 1 to 5 because its ranges are Australian. A total on Kessler's scale is 10 points lower with the same meaning. The authors publish no K10 ranges of their own. The Australian Bureau of Statistics says "no universally agreed categories" exist and describes other groupings, such as one for primary care: 10 to 19 likely to be well, 20 to 24 likely a mild disorder, 25 to 29 likely a moderate disorder, 30 to 50 likely a severe disorder.

The K10 measures general distress. It can't say what's behind a score or tell anxiety from depression, and it isn't built to find bipolar disorder, OCD or psychosis. It covers only the past 30 days, so it can't separate a long-running problem from a reaction to a recent loss, illness or job change.

None of the ten questions asks about suicide or self-harm, so a low score says nothing about those thoughts. The ranges come from Australian surveys and aren't universally agreed. We found no study of this page's version, so read your score as a rough guide.

A score describes the past 30 days, not who you are. At 10 to 15 there's nothing in particular to do, and you can retake it in a month to see if it holds. At 16 to 21, look at what's taking your energy: short sleep, workload, a conflict that won't end. At 22 to 29, talk with a doctor or therapist. The anxiety test and the depression test can show which one is louder. At 30 to 50, please see a doctor or therapist in the next few days. You can ask for help at any score.

If you're thinking about suicide or hurting yourself, call or text 988 (the 988 Suicide & Crisis Lifeline), which is free and open 24/7, or text HOME to 741741. Call 911 if you're in immediate danger.

More on this topic: Anxiety test (GAD-7), Depression test (PHQ-9), Stress test (PSS-10), DASS-21.

Your answers are scored in your browser. If you sign in and choose to save a result, we store the score and its label, not your individual answers. Without an account, nothing is saved.

• Kessler, K10 and K6 Scales (Harvard): the developer's page: terms of use, the citation and copyright line it asks for, the forms and the scoring notes.
• K10 self-administered form (Internet Archive copy of the Harvard file): the English wording of the ten items and the five answers used on this page.
• Kessler, Andrews, Colpe and colleagues, Psychological Medicine, 2002 (PubMed): abstract only: how the scales were built, precision, group consistency, surveys that use them.
• Kessler, Barker, Colpe and colleagues, Archives of General Psychiatry, 2003 (PubMed): abstract only: 155 people, serious mental illness, area under the curve, K6 sensitivity and specificity. This is the paper Kessler asks users to cite.
• Andrews and Slade, Australian and New Zealand Journal of Public Health, 2001 (PubMed): abstract only: K10 scores compared with symptoms, disability, service use and diagnosis in an Australian survey.
• Australian Bureau of Statistics, Information Paper 4817.0.55.001, K10 scoring: the 1 to 5 scoring, the four ranges on this page, the primary care grouping, and the statement that no categories are universally agreed.