A statistical analysis of CORE-OM scores obtained at the intake assessment and again immediately before the start of therapy for 230 people seen in a primary care psychology service – a service designed to offer brief cognitive behavioural therapy (CBT) for the treatment of mild-to-moderate depressive and anxiety disorders – reveals a significant improvement for the total score and the domain scores of symptoms, wellbeing, life functioning and risk. The differences reported in this study are larger than the test–retest differences reported for CORE-OM, and are not associated with the length of the wait. However, while other studies have also reported changed psychometric scores over the duration of the wait, this study considers the clinical significance of the changes observed. Individual change statistics indicate that 16.5% of the sample achieved reliable and clinically significant improvement, 12.2% showed reliable improvement only, 67.8% did not show any reliable change, while 3.5% reliably deteriorated before the start of therapy. As for those scoring on or above the clinical cut-off points at the assessment, the proportions were 25.2%, 14.6%, 57.6% and 2.6% respectively.