To score the K10, rate each of the 10 items from 1 ("none of the time") to 5 ("all of the time") and add them up, giving a total between 10 and 50. The Australian Bureau of Statistics groups totals as low (10-15), moderate (16-21), high (22-29) and very high (30-50) psychological distress.
That is the quick answer. The part that trips clinicians up is that it is not the only set of bands in use in Australia, and the one printed on the form in front of you may not be the one your colleague, your PHN or a research paper is using.
What is the K10 and what does it measure?
The Kessler Psychological Distress Scale (K10) is a 10-item self-report questionnaire about how often a person has felt tired out for no good reason, nervous, so nervous that nothing could calm them down, hopeless, restless or fidgety, so restless they could not sit still, depressed, that everything was an effort, so sad that nothing could cheer them up, and worthless.
It was developed by Ronald Kessler and Daniel Mroczek and published with colleagues in 2002. The Department of Health's K10+ scoring guide describes it as a global measure of "non-specific psychosocial distress" and calls it a simple "thermometer" that detects general distress "without identifying its cause". That framing matters. The K10 tells you how distressed someone has been, not why, and not what diagnosis fits.
In Australian use the rating period is the past four weeks. The scoring guide notes the standard period is 30 days, but Australian services have settled on four weeks.
How do you score the K10?
Each item uses the same five response options, scored as follows in Australian practice (per the ABS K10 information paper):
- None of the time: 1
- A little of the time: 2
- Some of the time: 3
- Most of the time: 4
- All of the time: 5
Add the 10 item scores. The minimum total is 10 (every answer "none of the time") and the maximum is 50.
Why do some K10 scores range from 0 to 40?
The same ABS paper notes that in the US the K10 is typically scored 0 to 4 per item, producing totals from 0 to 40. If you are reading an American study or using an overseas calculator, a US total converts to the Australian scale by adding 10. Applying Australian bands to an unconverted US score will make every client look 10 points less distressed than they are.
One more historical trap: in the 1997 National Survey of Mental Health and Wellbeing, the scoring was reversed so that low scores meant high distress. The ABS flags this for anyone working with that dataset. It rarely affects clinical work, but it explains some confusing tables in older papers.
What do K10 score ranges mean?
Here is the key point, in the ABS's own words: "no universally agreed categories or groupings exist for K10 scores". Several banding schemes are used in Australia depending on the setting.
ABS population bands (four levels)
Used in ABS health surveys and the 2020-21 National Study of Mental Health and Wellbeing:
- 10-15: low (little or no psychological distress)
- 16-21: moderate
- 22-29: high
- 30-50: very high
The ABS says it built these groupings from the work of the Clinical Research Unit for Anxiety and Depression (CRUfAD), Andrews and Slade (2001) and Korten. Andrews and Slade used the national survey to provide normative data linking K10 scores with symptoms, disability, service use and diagnosis.
CRUfAD and GPcare primary care bands
The ABS paper also reproduces the groupings used by CRUfAD and GPcare in primary healthcare, which are intended to help monitor distress rather than identify a disorder:
- 10-19: likely to be well
- 20-24: likely to have a mild mental disorder
- 25-29: likely to have a moderate mental disorder
- 30-50: likely to have a severe mental disorder
Specialist mental health services use the same cut-offs with softer wording, for example "may be experiencing moderate levels of distress consistent with a diagnosis of a moderate depression and/or anxiety disorder".
A three-level "plain English" version
A third grouping, developed with AMHOCN and the Mental Health Association of NSW for the 2002 Healthy Mind Day questionnaire, uses three levels: 10-15, 16-30 and 31-50.
What does a K10 score of 20, 27 or 30 mean?
Because the schemes disagree below 30, the same number can carry quite different labels:
- A score of 18 is "moderate" on the ABS bands but "likely to be well" on the CRUfAD bands.
- A score of 20 is "moderate" (ABS), "likely to have a mild mental disorder" (CRUfAD) and "moderate symptoms" (plain English).
- A score of 27 is "high" (ABS) and "likely to have a moderate mental disorder" (CRUfAD).
- A score of 30 is "very high" (ABS) and "likely to have a severe mental disorder" (CRUfAD). Under the plain English version, 30 is still in the middle band; the top band starts at 31.
The schemes line up best at the top end, where 30 or more is treated as very high or severe distress by both four-level systems. The ABS National Health Survey users' guide notes that, based on other population studies, a very high K10 score "may indicate a need for professional help".
The practical rule: name the scheme whenever you write down a label. "K10 = 27 (high, ABS bands)" is interpretable by the next reader. "K10 = 27, moderate" is not, because it depends which table you used.
How common are high K10 scores in Australia?
For context when you explain a score to a client, the ABS found that in 2020-21, 15% of Australians aged 16-85 experienced high or very high psychological distress (a K10 of 22 or more). The rate was 19% for women and 12% for men, and 20% for people aged 16-34, more than twice the rate for people aged 65-85 (9%).
How do you handle missing K10 items?
This is where the documentation has shifted, and many templates have not caught up.
The Department of Health's K10+ scoring guide (dated 1 October 2021) says a completed K10 with more than one missing item is invalid, and that a single missing item is simply left out of the total. The Primary Mental Health Care Minimum Data Set (PMHC MDS) then announced a change taking effect in the last week of October 2021. The old method could produce a "valid" total of 9, below the scale's floor. The replacement pro-rates one missing item:
- Total score = round(sum of the nine valid item scores ÷ 9 × 10)
- More than one missing item: the total is invalid and recorded as missing
So a client who answers nine items with a sum of 24 has a pro-rated total of 27, not 24. If you report to a PHN through the PMHC MDS, use the pro-rated method. Whatever you use, note in the record that the score was pro-rated.
What are the extra questions on the K10+?
The K10+ used across Australian primary mental health care adds four questions: days totally unable to work, study or manage day-to-day activities; days they had to cut down; number of consultations with a health professional about these feelings; and how often physical health problems were the main cause.
These are not part of the total. The scoring guide excludes items 11 to 14 because they measure disability associated with the distress, separate from the distress itself. Clients who answer "none of the time" to all 10 distress items do not need to answer them.
The guide also mentions the K5, a five-item subset of the K10 selected to be suitable for use with Aboriginal and Torres Strait Islander clients. It is scored 5 to 25, so K10 bands cannot be applied to it.
How is the K10 used in Mental Health Treatment Plans?
The MBS explanatory note AN.0.56 requires the assessment for a Mental Health Treatment Plan to include an outcome measurement tool, unless clinically inappropriate, and names the K10 and DASS 21 as examples. The same tool is re-administered at plan review, again unless clinically inappropriate.
For psychologists receiving a referral, this means the GP's K10 is often your first data point. Re-administering the same measure, over the same four-week period and read against the same bands, keeps the numbers comparable. Our guides to Mental Health Treatment Plans and writing depression treatment plan objectives cover how to build measurable objectives around outcome scores.
How should you document a K10 in clinical notes?
A K10 entry that will still make sense at review, or to another clinician, records:
- The date administered and the rating period (past four weeks)
- The total, and whether it was pro-rated for a missing item
- The banding scheme used alongside the label
- Any items that stood out, such as "hopeless" or "worthless" endorsed "most of the time"
- The comparison point (the GP's referral score or your last administration)
One caution: the K10 does not ask about suicidal thoughts or behaviour, so neither a low nor a high score is a risk assessment. If items like hopelessness or worthlessness are elevated, follow up clinically and document the suicide risk assessment separately. For wider note structure, see our mental health progress notes guide.
Scoring by hand invites small arithmetic and banding errors, especially once pro-rating is involved. PractaLuma is AI-native practice management software for Australian mental-health practices, and its standardised assessments let you send, score and track the K10, DASS-21, PHQ-9, GAD-7 and other measures so scores sit in the client record over time.
Frequently asked questions
What is a normal K10 score? There is no single "normal" cut-off. On the ABS bands, 10-15 indicates little or no psychological distress. On the CRUfAD primary care bands, 10-19 is "likely to be well".
Is the K10 a diagnostic tool? No. It measures non-specific psychological distress and does not identify its cause. Any diagnosis needs a clinical assessment.
Can I compare a K10 score with a DASS-21 score? Not directly. They are different instruments with different scales and cut-offs. Track change within the same measure over time.
What if a client leaves two K10 questions blank? Under the PMHC MDS rules, a K10 with more than one missing item is invalid and recorded as missing. Ask the client to complete the missing items where possible.
This guide summarises published scoring conventions for clinicians. It is not a substitute for clinical judgement or your organisation's reporting requirements.