Title: Regression discontinuity analysis of case finding for depression in primary care
Funder: Department of Health and Social Care

Abstract: Aim: To undertake a regression discontinuity (RD) study, with embedded qualitative and economic evaluations, to ascertain whether screening with the Geriatric Depression Scale (GDS) followed by alerting the GPs of severely depressed patients improves depression score six months later. Participants: We will identify participants, based in Northern England, via three methods: a cohort of older people (n~1500) who were originally recruited from primary care for the OTIS study; second, a cohort of arthroplasty patients recruited from Northern hospitals into the KReBS study (n~850); and third, we will identify GP practices in Hull, Leeds, Newcastle and York (10 in total) to undertake case finding within their practice. We will ask each practice to mail out to 800 adults over 65 years old. Methods: We will mail out potential participants an information sheet and a baseline questionnaire collecting basic demographic information, GDS and EuroQol 5D 5-level (EQ-5D-5L). From those who return the questionnaire, we will identify those who score &ge;10 on the GDS and notify their GP. Follow-up at six months will include: GDS; health care resource use in terms of GP and mental health services including medications; and EQ-5D-5L to undertake a cost-utility analysis. We will assess the impact of the intervention by running a RD analysis using the GDS score at six months as the primary outcome. In the 10 practices we will conduct qualitative interviews with a range of staff (n=20 including GPs, practice managers, practice nurses) to explore the acceptability and feasibility of this intervention, the types of treatments available, and offered to, older people with depression and how case finding could be incorporated into routine general practice. In addition, we will interview 25 participants (purposively sampled on the basis of age, gender, socio-economic position and GDS score) to explore acceptability of the intervention, and conduct thematic analysis.

Lay abstract: One in four people aged 65-plus are depressed. Most do not receive help from the NHS. There is little evidence that actively trying to find out who has depression to offer help (aka screening) could improve this situation. However, when we screened 895 podiatry patients aged 65-plus for depression in a previous falls prevention trial, it reduced symptoms among the severely depressed (about 6 in 100 people). Participants completed the Geriatric Depression Scale (GDS) questionnaire when joining the trial, and after six and 12 months. If their score suggested severe depression, we alerted their GP (for ethical reasons) and asked the GP to contact the patient. We measured the impact of this six months later. Our plan is to repeat this study involving more people. We will recruit 2000 participants across Northern England by post. We will ask them to complete the GDS and questions on quality of life and some general background information. They will receive the same questionnaire again after six months, along with questions about any GP visits, medications and treatments they have received in the last six months. In addition, we will interview GPs, practice managers and practice nurses (20 in total) from 10 GP practices in Northern cities to learn about treatments offered to depressed elderly people, and to explore if and how screening could be incorporated in practice. We will interview 25 participants about their views on screening for depression. This will help us determine if screening and making recommendations to GPs is good value for money. We will work with patient contributors on aspects such as the content and wording of information for (potential) participants and the general public. We will share study results with participants and publish in open access, peer-reviewed medical journals, and publications aimed at GPs.

Research activity codes: 4.4 POPULATION SCREENING
Health categories: MENTAL HEALTH