Behavioural Activation for Social IsoLation (BASIL+) trial (Behavioural activation to mitigate depression and loneliness among older people with long-term conditions): Protocol for a fully-powered pragmatic randomised controlled trial.

INTRODUCTION: Depression is a leading mental health problem worldwide. People with long-term conditions are at increased risk of experiencing depression. The COVID-19 pandemic led to strict social restrictions being imposed across the UK population. Social isolation can have negative consequences on the physical and mental wellbeing of older adults. In the Behavioural Activation in Social IsoLation (BASIL+) trial we will test whether a brief psychological intervention (based on Behavioural Activation), delivered remotely, can mitigate depression and loneliness in older adults with long-term conditions during isolation. METHODS: We will conduct a two-arm, parallel-group, randomised controlled trial across several research sites, to evaluate the clinical and cost-effectiveness of the BASIL+ intervention. Participants will be recruited via participating general practices across England and Wales. Participants must be aged ≥65 with two or more long-term conditions, or a condition that may indicate they are within a 'clinically extremely vulnerable' group in relation to COVID-19, and have scored ≥5 on the Patient Health Questionnaire (PHQ9), to be eligible for inclusion. Randomisation will be 1:1, stratified by research site. Intervention participants will receive up to eight intervention sessions delivered remotely by trained BASIL+ Support Workers and supported by a self-help booklet. Control participants will receive usual care, with additional signposting to reputable sources of self-help and information, including advice on keeping mentally and physically well. A qualitative process evaluation will also be undertaken to explore the acceptability of the BASIL+ intervention, as well as barriers and enablers to integrating the intervention into participants' existing health and care support, and the impact of the intervention on participants' mood and general wellbeing in the context of the COVID-19 restrictions. Semi-structured interviews will be conducted with intervention participants, participant's caregivers/supportive others and BASIL+ Support Workers. Outcome data will be collected at one, three, and 12 months post-randomisation. Clinical and cost-effectiveness will be evaluated. The primary outcome is depressive symptoms at the three-month follow up, measured by the PHQ9. Secondary outcomes include loneliness, social isolation, anxiety, quality of life, and a bespoke health services use questionnaire. DISCUSSION: This study is the first large-scale trial evaluating a brief Behavioural Activation intervention in this population, and builds upon the results of a successful external pilot trial. TRIAL REGISTRATION: ClinicalTrials.Gov identifier ISRCTN63034289, registered on 5th February 2021.

Behavioural activation to prevent depression and loneliness among socially isolated older people with long-term conditions: The BASIL COVID-19 pilot randomised controlled trial.

BACKGROUND: Older adults, including those with long-term conditions (LTCs), are vulnerable to social isolation. They are likely to have become more socially isolated during the Coronavirus Disease 2019 (COVID-19) pandemic, often due to advice to "shield" to protect them from infection. This places them at particular risk of depression and loneliness. There is a need for brief scalable psychosocial interventions to mitigate the psychological impacts of social isolation. Behavioural activation (BA) is a credible candidate intervention, but a trial is needed. METHODS AND FINDINGS: We undertook an external pilot parallel randomised trial (ISRCTN94091479) designed to test recruitment, retention and engagement with, and the acceptability and preliminary effects of the intervention. Participants aged ≥65 years with 2 or more LTCs were recruited in primary care and randomised by computer and with concealed allocation between June and October 2020. BA was offered to intervention participants (n = 47), and control participants received usual primary care (n = 49). Assessment of outcome was made blind to treatment allocation. The primary outcome was depression severity (measured using the Patient Health Questionnaire 9 (PHQ-9)). We also measured health-related quality of life (measured by the Short Form (SF)-12v2 mental component scale (MCS) and physical component scale (PCS)), anxiety (measured by the Generalised Anxiety Disorder 7 (GAD-7)), perceived social and emotional loneliness (measured by the De Jong Gierveld Scale: 11-item loneliness scale). Outcome was measured at 1 and 3 months. The mean age of participants was aged 74 years (standard deviation (SD) 5.5) and they were mostly White (n = 92, 95.8%), and approximately two-thirds of the sample were female (n = 59, 61.5%). Remote recruitment was possible, and 45/47 (95.7%) randomised to the intervention completed 1 or more sessions (median 6 sessions) out of 8. A total of 90 (93.8%) completed the 1-month follow-up, and 86 (89.6%) completed the 3-month follow-up, with similar rates for control (1 month: 45/49 and 3 months 44/49) and intervention (1 month: 45/47and 3 months: 42/47) follow-up. Between-group comparisons were made using a confidence interval (CI) approach, and by adjusting for the covariate of interest at baseline. At 1 month (the primary clinical outcome point), the median number of completed sessions for people receiving the BA intervention was 3, and almost all participants were still receiving the BA intervention. The between-group comparison for the primary clinical outcome at 1 month was an adjusted between-group mean difference of -0.50 PHQ-9 points (95% CI -2.01 to 1.01), but only a small number of participants had completed the intervention at this point. At 3 months, the PHQ-9 adjusted mean difference (AMD) was 0.19 (95% CI -1.36 to 1.75). When we examined loneliness, the adjusted between-group difference in the De Jong Gierveld Loneliness Scale at 1 month was 0.28 (95% CI -0.51 to 1.06) and at 3 months -0.87 (95% CI -1.56 to -0.18), suggesting evidence of benefit of the intervention at this time point. For anxiety, the GAD adjusted between-group difference at 1 month was 0.20 (-1.33, 1.73) and at 3 months 0.31 (-1.08, 1.70). For the SF-12 (physical component score), the adjusted between-group difference at 1 month was 0.34 (-4.17, 4.85) and at 3 months 0.11 (-4.46, 4.67). For the SF-12 (mental component score), the adjusted between-group difference at 1 month was 1.91 (-2.64, 5.15) and at 3 months 1.26 (-2.64, 5.15). Participants who withdrew had minimal depressive symptoms at entry. There were no adverse events. The Behavioural Activation in Social Isolation (BASIL) study had 2 main limitations. First, we found that the intervention was still being delivered at the prespecified primary outcome point, and this fed into the design of the main trial where a primary outcome of 3 months is now collected. Second, this was a pilot trial and was not designed to test between-group differences with high levels of statistical power. Type 2 errors are likely to have occurred, and a larger trial is now underway to test for robust effects and replicate signals of effectiveness in important secondary outcomes such as loneliness. CONCLUSIONS: In this study, we observed that BA is a credible intervention to mitigate the psychological impacts of COVID-19 isolation for older adults. We demonstrated that it is feasible to undertake a trial of BA. The intervention can be delivered remotely and at scale, but should be reserved for older adults with evidence of depressive symptoms. The significant reduction in loneliness is unlikely to be a chance finding, and replication will be explored in a fully powered randomised controlled trial (RCT). TRIAL REGISTRATION: ISRCTN94091479.

Dupuytren's interventions surgery versus collagenase (DISC) trial: study protocol for a pragmatic, two-arm parallel-group, non-inferiority randomised controlled trial.

BACKGROUND: Dupuytren's contracture is a fibro-proliferative disease of the hands affecting over 2 million UK adults, particularly the white, male population. Surgery is the traditional treatment; however, recent studies have indicated that an alternative to surgery-collagenase clostridium histolyticum (collagenase)-is better than a placebo in the treatment of Dupuytren's contracture. There is however no robust randomised controlled trial that provides a definitive answer on the clinical effectiveness of collagenase compared with limited fasciectomy surgery. Dupuytren's intervention surgery vs collagenase trial (DISC) trial was therefore designed to fill this evidence gap. METHODS/DESIGN: The DISC trial is a multi-centre pragmatic two-arm parallel-group, randomised controlled trial. Participants will be assigned 1:1 to receive either collagenase injection or surgery (limited fasciectomy). We aim to recruit 710 adult participants with Dupuytren's contracture. Potential participants will be identified in primary and secondary care, screened by a delegated clinician and if eligible and consenting, baseline data will be collected and randomisation completed. The primary outcome will be the self-reported patient evaluation measure assessed 1 year after treatment. Secondary outcome measures include the Unité Rhumatologique des Affections de la Main Scale, the Michigan Hand Questionnaire, EQ-5D-5L, resource use, further procedures, complications, recurrence, total active movement and extension deficit, and time to return to function. Given the limited evidence comparing recurrence rates following collagenase injection and limited fasciectomy, and the importance of a return to function as soon as possible for patients, the associated measures for each will be prioritised to allow treatment effectiveness in the context of these key elements to be assessed. An economic evaluation will assess the cost-effectiveness of treatments, and a qualitative sub-study will assess participants' experiences and preferences of the treatments. DISCUSSION: The DISC trial is the first randomised controlled trial, to our knowledge, to investigate the clinical and cost-effectiveness of collagenase compared to limited fasciectomy surgery for patients with Dupuytren's contracture. TRIAL REGISTRATION: Clinical.Trials.gov ISRCTN18254597 . Registered on April 11, 2017.

An assessment of the extent to which the contents of PROSPERO records meet the systematic review protocol reporting items in PRISMA-P.

Background: PROSPERO is an international prospective register for systematic review protocols. Many of the registrations are the only available source of information about planned methods. This study investigated the extent to which records in PROSPERO contained the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P). Methods: A random sample of 439 single entry PROSPERO records of reviews of health interventions registered in 2018 was identified. Using a piloted list of 19 PRISMA-P items, divided into 63 elements, two researchers independently assessed the registration records. Where the information was present or not applicable to the review, a score of 1 was assigned. Overall scores were calculated and comparisons made by stage of review at registration, whether or not a meta-analysis was planned and whether or not funding/sponsorship was reported. Results: Some key methodological details, such as eligibility criteria, were relatively frequently reported, but much of the information recommended in PRISMA-P was not stated in PROSPERO registrations. Considering the 19 items, the mean score was 4.8 (SD 1.8; median 4; range 2-11) and across all the assessed records only 25% (2081/8227) of the items were scored as reported. Considering the 63 elements, the mean score was 33.4 (SD 5.8; median 33; range 18-47) and overall, 53% (14,469/27,279) of the elements were assessed as reported. Reporting was more frequent for items required in PROSPERO than optional items. The planned comparisons showed no meaningful differences between groups. Conclusions: PROSPERO provides reviewers with the opportunity to be transparent in their planned methods and demonstrate efforts to reduce bias. However, where the PROSPERO record is the only available source of a priori reporting, there is a significant shortfall in the items reported, compared to those recommended. This presents challenges in interpretation for those wishing to assess the validity of the final review.

Sexual health promotion in people with severe mental illness: the RESPECT feasibility RCT.

BACKGROUND: People with serious mental illness have sexual health needs, but there is limited evidence regarding effective interventions to promote their sexual health. OBJECTIVES: To develop a sexual health promotion intervention for people with serious mental illness, and to conduct a feasibility trial in order to establish the acceptability and parameters for a fully powered trial. DESIGN: A two-armed randomised controlled, open feasibility study comparing usual care alone with usual care plus the adjunctive intervention. SETTING: Five community mental health providers in Leeds, Barnsley, Brighton and London. PARTICIPANTS: Adults aged ≥ 18 years with serious mental illness and receiving care from community mental health teams. INTERVENTIONS: A remote, web-based computer randomisation system allocated participants to usual care plus the RESPECT (Randomised Evaluation of Sexual health Promotion Effectiveness informing Care and Treatment) intervention (three sessions of 1 hour) (intervention arm) or usual care only (control arm). The intervention was an interactive manualised package of exercises, quizzes and discussion topics focusing on knowledge, motivation and behavioural intentions to adopt safer sexual behaviours. MAIN OUTCOME MEASURES: Feasibility parameters including establishing the percentage of people who were eligible, consented and were retained in each arm of the trial, retention for the intervention, as well as the completeness of the data collection. Data were collected on knowledge, motivation to adopt safer sexual behaviour, sexual behaviour, sexual stigma, sexual health service use and quality of life. Data were collected at baseline and then at 3 months and 6 months post randomisation. RESULTS: Of a target of 100 participants, 72 people participated in the trial over 12 months. Of the 36 participants randomised to the intervention arm, 27 received some of the intervention (75.0%). At 3 months, 59 of the 72 participants completed follow-up questionnaires (81.9%) (30 participants from the intervention arm and 29 participants from the control arm). Only the first 38 participants were followed up at 6 months. However, data were collected on 29 out of 38 participants (76.3% retention): 13 in the intervention arm and 16 in the control arm. No adverse events were reported. Participant feedback confirmed that both the design and the intervention were acceptable. The economic analysis indicated high completion rates and completeness of data among participants who continued the trial. CONCLUSIONS: Despite the limitations, the findings suggest that it is both acceptable and feasible to undertake a sexual health promotion study for people with serious mental illness. FUTURE WORK: A fully powered randomised controlled trial would be required to establish the clinical effectiveness of the intervention. TRIAL REGISTRATION: Current Controlled Trials ISRCTN15747739. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 23, No. 65. See the NIHR Journals Library website for further project information.

A team of researchers, mental health and sexual health workers, and people with lived experience of mental health problems developed an intervention to help people with serious mental health problems to increase their knowledge and understanding of sexual health, including types of contraception, using condoms safely and sexually transmitted infections, and to consider safety and assertiveness in intimate relationships. This was delivered over three sessions of 1 hour by a specifically trained mental health worker. We recruited 72 people from community mental health services to take part in a study to test the intervention and see whether or not we could collect information about their sexual behaviour using questionnaires. Initially, the numbers of people volunteering for the study were very small. We found that recruitment increased when we shifted to a more direct approach (rather than asking clinical staff to promote the study to people on their caseloads). The direct approach included talking to people who use services directly in clinics and at service user events, and by sending study information by post. We were not able to recruit the numbers that we aimed to (72/100 participants) in the timescale of the study, but the majority of the people who were recruited actively participated in the trial and were generally happy to attend follow-up appointments to complete more questionnaires. Most of those who were allocated to the intervention attended all three sessions. Overall, people found that being a participant of the study was comfortable and safe (acceptable) and we found that it was possible to undertake this type of study within mental health services. We have learnt a lot about how we could run this study on a larger scale. Such a study would allow us to see if the intervention makes a difference to sexual behaviour and increases access to sexual health services for people with serious mental illness.

CollAborative care for Screen-Positive EldeRs with major depression (CASPER plus): a multicentred randomised controlled trial of clinical effectiveness and cost-effectiveness.

BACKGROUND: Depression in older adults is common and is associated with poor quality of life, increased morbidity and early mortality, and increased health and social care use. Collaborative care, a low-intensity intervention for depression that is shown to be effective in working-age adults, has not yet been evaluated in older people with depression who are managed in UK primary care. The CollAborative care for Screen-Positive EldeRs (CASPER) plus trial fills the evidence gap identified by the most recent guidelines on depression management. OBJECTIVES: To establish the clinical effectiveness and cost-effectiveness of collaborative care for older adults with major depressive disorder in primary care. DESIGN: A pragmatic, multicentred, two-arm, parallel, individually randomised controlled trial with embedded qualitative study. Participants were automatically randomised by computer, by the York Trials Unit Randomisation Service, on a 1 : 1 basis using simple unstratified randomisation after informed consent and baseline measures were collected. Blinding was not possible. SETTING: Sixty-nine general practices in the north of England. PARTICIPANTS: A total of 485 participants aged ≥ 65 years with major depressive disorder. INTERVENTIONS: A low-intensity intervention of collaborative care, including behavioural activation, delivered by a case manager for an average of six sessions over 7-8 weeks, alongside usual general practitioner (GP) care. The control arm received only usual GP care. MAIN OUTCOME MEASURES: The primary outcome measure was Patient Health Questionnaire-9 items score at 4 months post randomisation. Secondary outcome measures included depression severity and caseness at 12 and 18 months, the EuroQol-5 Dimensions, Short Form questionnaire-12 items, Patient Health Questionnaire-15 items, Generalised Anxiety Disorder-7 items, Connor-Davidson Resilience Scale-2 items, a medication questionnaire, objective data and adverse events. Participants were followed up at 12 and 18 months. RESULTS: In total, 485 participants were randomised (collaborative care, n = 249; usual care, n = 236), with 390 participants (80%: collaborative care, 75%; usual care, 86%) followed up at 4 months, 358 participants (74%: collaborative care, 70%; usual care, 78%) followed up at 12 months and 344 participants (71%: collaborative care, 67%; usual care, 75%) followed up at 18 months. A total of 415 participants were included in primary analysis (collaborative care, n = 198; usual care, n = 217), which revealed a statistically significant effect in favour of collaborative care at the primary end point at 4 months [8.98 vs. 10.90 score points, mean difference 1.92 score points, 95% confidence interval (CI) 0.85 to 2.99 score points; p < 0.001], equivalent to a standard effect size of 0.34. However, treatment differences were not maintained in the longer term (at 12 months: 0.19 score points, 95% CI -0.92 to 1.29 score points; p = 0.741; at 18 months: < 0.01 score points, 95% CI -1.12 to 1.12 score points; p = 0.997). The study recorded details of all serious adverse events (SAEs), which consisted of 'unscheduled hospitalisation', 'other medically important condition' and 'death'. No SAEs were related to the intervention. Collaborative care showed a small but non-significant increase in quality-adjusted life-years (QALYs) over the 18-month period, with a higher cost. Overall, the mean cost per incremental QALY for collaborative care compared with usual care was £26,016; however, for participants attending six or more sessions, collaborative care appears to represent better value for money (£9876/QALY). LIMITATIONS: Study limitations are identified at different stages: design (blinding unfeasible, potential contamination), process (relatively low overall consent rate, differential attrition/retention rates) and analysis (no baseline health-care resource cost or secondary/social care data). CONCLUSION: Collaborative care was effective for older people with case-level depression across a range of outcomes in the short term though the reduction in depression severity was not maintained over the longer term of 12 or 18 months. Participants who received six or more sessions of collaborative care did benefit substantially more than those who received fewer treatment sessions but this difference was not statistically significant. FUTURE WORK RECOMMENDATIONS: Recommendations for future research include investigating the longer-term effect of the intervention. Depression is a recurrent disorder and it would be useful to assess its impact on relapse and the prevention of future case-level depression. TRIAL REGISTRATION: Current Controlled Trials ISRCTN45842879. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 67. See the NIHR Journals Library website for further project information.

CollAborative care and active surveillance for Screen-Positive EldeRs with subthreshold depression (CASPER): a multicentred randomised controlled trial of clinical effectiveness and cost-effectiveness.

BACKGROUND: Efforts to reduce the burden of illness and personal suffering associated with depression in older adults have focused on those with more severe depressive syndromes. Less attention has been paid to those with mild disorders/subthreshold depression, but these patients also suffer significant impairments in their quality of life and level of functioning. There is currently no clear evidence-based guidance regarding treatment for this patient group. OBJECTIVES: To establish the clinical effectiveness and cost-effectiveness of a low-intensity intervention of collaborative care for primary care older adults who screened positive for subthreshold depression. DESIGN: A pragmatic, multicentred, two-arm, parallel, individually randomised controlled trial with a qualitative study embedded within the pilot. Randomisation occurred after informed consent and baseline measures were collected. SETTING: Thirty-two general practitioner (GP) practices in the north of England. PARTICIPANTS: A total of 705 participants aged ≥ 75 years during the pilot phase and ≥ 65 years during the main trial with subthreshold depression. INTERVENTIONS: Participants in the intervention group received a low-intensity intervention of collaborative care, which included behavioural activation delivered by a case manager for an average of six sessions over 7-8 weeks, alongside usual GP care. Control-arm participants received only usual GP care. MAIN OUTCOME MEASURES: The primary outcome measure was a self-reported measure of depression severity, the Patient Health Questionnaire-9 items PHQ-9 score at 4 months post randomisation. Secondary outcome measures included the European Quality of Life-5 Dimensions, Short Form questionnaire-12 items, Patient Health Questionnaire-15 items, Generalised Anxiety Disorder seven-item scale, Connor-Davidson Resilience Scale two-item version, a medication questionnaire and objective data. Participants were followed up for 12 months. RESULTS: In total, 705 participants were randomised (collaborative care n = 344, usual care n = 361), with 586 participants (83%; collaborative care 76%, usual care 90%) followed up at 4 months and 519 participants (74%; collaborative care 68%, usual care 79%) followed up at 12 months. Attrition was markedly greater in the collaborative care arm. Model estimates at the primary end point of 4 months revealed a statistically significant effect in favour of collaborative care compared with usual care [mean difference 1.31 score points, 95% confidence interval (CI) 0.67 to 1.95 score points; p < 0.001]. The difference equates to a standard effect size of 0.30, for which the trial was powered. Treatment differences measured by the PHQ-9 were maintained at 12 months' follow-up (mean difference 1.33 score points, 95% CI 0.55 to 2.10 score points; p = 0.001). Base-case cost-effectiveness analysis found that the incremental cost-effectiveness ratio was £9633 per quality-adjusted life-year (QALY). On average, participants allocated to collaborative care displayed significantly higher QALYs than those allocated to the control group (annual difference in adjusted QALYs of 0.044, 95% bias-corrected CI 0.015 to 0.072; p = 0.003). CONCLUSIONS: Collaborative care has been shown to be clinically effective and cost-effective for older adults with subthreshold depression and to reduce the proportion of people who go on to develop case-level depression at 12 months. This intervention could feasibly be delivered in the NHS at an acceptable cost-benefit ratio. Important future work would include investigating the longer-term effect of collaborative care on the CASPER population, which could be conducted by introducing an extension to follow-up, and investigating the impact of collaborative care on managing multimorbidities in people with subthreshold depression. TRIAL REGISTRATION: Current Controlled Trials ISRCTN02202951. FUNDING: This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 21, No. 8. See the NIHR Journals Library website for further project information.

Identification of depression in women during pregnancy and the early postnatal period using the Whooley questions and the Edinburgh Postnatal Depression Scale: protocol for the Born and Bred in Yorkshire: PeriNatal Depression Diagnostic Accuracy (BaBY PaNDA) study.

INTRODUCTION: Perinatal depression is well recognised as a mental health condition but <50% of cases are identified by healthcare professionals in routine clinical practice. The Edinburgh Postnatal Depression Scale (EPDS) is often used to detect symptoms of postnatal depression in maternity and child services. The National Institute for Health and Care Excellence (NICE) recommends 2 'ultra-brief' case-finding questions (the Whooley questions) to aid identification of depression during the perinatal period, but this recommendation was made in the absence of any validation studies in a perinatal population. Limited research exists on the acceptability of these depression case-finding instruments and the cost-effectiveness of routine screening for perinatal depression. METHODS AND ANALYSIS: The diagnostic accuracy of the Whooley questions and the EPDS will be determined against a reference standard (the Client Interview Schedule-Revised) during pregnancy (around 20 weeks) and the early postnatal period (around 3-4 months post partum) in a sample of 379 women. Further outcome measures will assess a range of psychological comorbidities, health-related quality of life and resource utilisation. Women will be followed up 12 months postnatally. The sensitivity, specificity and predictive values of the Whooley questions and the EPDS will be calculated against the reference standard at 20 weeks pregnancy and 3-4 months post partum. Acceptability of the depression case-finding instruments to women and healthcare professionals will involve in-depth qualitative interviews. An existing decision analytic model will be adapted to determine the cost-effectiveness of routine screening for perinatal depression. ETHICS AND DISSEMINATION: This study is considered low risk for participants. Robust protocols will deal with cases where risk of depression, self-harm or suicide is identified. The protocol received favourable ethical opinion from the North East-York Research Ethics Committee (reference: 11/NE/0022). The study findings will be published in peer-reviewed journals and presented at relevant conferences.

CASPER plus (CollAborative care in Screen-Positive EldeRs with major depressive disorder): study protocol for a randomised controlled trial.

BACKGROUND: Depression accounts for the greatest disease burden of all mental health disorders, contributes heavily to healthcare costs, and by 2020 is set to become the second largest cause of global disability. Although 10% to 16% of people aged 65 years and over are likely to experience depressive symptoms, the condition is under-diagnosed and often inadequately treated in primary care. Later-life depression is associated with chronic illness and disability, cognitive impairment and social isolation. With a progressively ageing population it becomes increasingly important to refine strategies to identity and manage depression in older people. Currently, management may be limited to the prescription of antidepressants where there may be poor concordance; older people may lack awareness of psychosocial interventions and general practitioners may neglect to offer this treatment option. METHODS/DESIGN: CASPER Plus is a multi-centre, randomised controlled trial of a collaborative care intervention for individuals aged 65 years and over experiencing moderate to severe depression. Selected practices in the North of England identify potentially eligible patients and invite them to participate in the study. A diagnostic interview is carried out and participants with major depressive disorder are randomised to either collaborative care or usual care. The recruitment target is 450 participants. The intervention, behavioural activation and medication management in a collaborative care framework, has been adapted to meet the complex needs of older people. It is delivered over eight to 10 weekly sessions by a case manager liaising with general practitioners. The trial aims to evaluate the clinical and cost effectiveness of collaborative care in addition to usual GP care versus usual GP care alone. The primary clinical outcome, depression severity, will be measured with the Patient Health Questionnaire-9 (PHQ-9) at baseline, 4, 12 and 18 months. Cost effectiveness analysis will assess health-related quality of life using the SF-12 and EQ-5D and will examine cost-consequences of collaborative care. A qualitative process evaluation will be undertaken to explore acceptability, gauge the extent to which the intervention is implemented and to explore sustainability beyond the clinical trial. DISCUSSION: Results will add to existing evidence and a positive outcome may lead to the commissioning of this model of service in primary care. TRIAL REGISTRATION: ISRCTN45842879 (24 July 2012).