PHQ-9 scoring calculator

The PHQ-9 was developed by Robert Spitzer, Janet Williams, Kurt Kroenke and colleagues in the late 1990s as part of the Patient Health Questionnaire family, and it became the standard depression measure in UK services because it is short, free to use and sensitive to change. Nine items, each scored 0 to 3 over the last two weeks, giving a total from 0 to 27.

The bands are a shorthand, not a verdict. A score is a snapshot of symptom frequency over a fortnight; it moves with sleep, physical illness, bereavement and shift work as well as with depression. What the bands are genuinely good for is conversation and trend: naming where things sit today, and noticing where they have moved since last month.

Routine measurement earns its minute. Clients like seeing change they can point at, a falling line is motivating in a way reassurance is not, and a flat line is clinical information too: it asks a question about the work that is better asked at session twelve than session forty. In NHS Talking Therapies, a score of 10 or more counts as above caseness and a change of 6 or more counts as reliable, which is useful shared language even in private practice.

The honest caveat: a falling score is not the same as a good outcome. Scores fall when people avoid what hurts, and rise when therapy touches something real; item 9 needs your attention every single time it is scored above zero. The measure informs clinical judgement and never replaces it.