The Kessler psychological distress scale (K10) [476] is a widely used, simple self-report measure of psychological distress which can be used to identify those in need of further assessment for anxiety and depression (Appendix M). This measure was designed for use in the general population; however, it may also serve as a useful clinical tool. The K10 comprises 10 questions that are answered using a five-point scale (where 5 = all of the time, and 1 = none of the time). For all questions, the client circles the answer truest for them in the past four weeks. Scores are then summed with the maximum score of 50 indicating severe distress, and the minimum score of 10 indicating no distress. A guide to interpreting K10 scores is provided in Table 28.
A number of studies have been conducted to test the reliability and validity of the K10, and its brief version, the K6. Good reliability and validity have been found when these measures have been used among people with AOD use disorders, as well as in the general population [477–480].
Table 28: Severity of psychological distress according to K10 score
| K10 score |
Level of psychological distress |
| 10-15 |
Low |
| 16-21 |
Moderate |
| 22-29 |
High |
| 30-50 |
Very high |
Adapted from Andrews and Slade [481].