OBJECTIVES
The UK's Improving Access to Psychological Therapies (IAPT) programme uses the Patient Health Questionnaire Depression Scale (PHQ-9; Kroenke, Spitzer, & Williams, , J. Gen. Intern. Med., 16, 606) and Generalized Anxiety Disorder Scale (GAD-7; Spitzer et al., Arch. Intern. Med., 166, 1092) to assess patients' symptoms of depression and anxiety respectively. Data are typically collecte...