CRD summary

This review concluded that there was robust evidence to show that collaborative care models were effective for treating depressive disorders in a wide range of populations, settings and organisations. Despite gaps in the reporting of the review, the conclusions appeared to reflect the evidence and are likely to be reliable.

Authors' objectives

To evaluate the effectiveness of collaborative care to improve the management of depressive disorders and identify the variables that influence the applicability and generalisability of collaborative care models to various populations and settings.

Searching

Ten electronic databases were consulted, including MEDLINE, EMBASE and The Cochrane Library. Five journals were consulted for articles published in the 10 years preceding the review. Unpublished papers, conference abstracts, reports, books and book chapters identified by reviewers and subject experts were searched. Searches were limited to studies in English. Searches were conducted up to February 2009. Studies published before 2004 were excluded as older relevant studies were included in a previous review (see Other Publications of Related Interest). Search terms were reported online.

Study selection

Studies that evaluated collaborative care interventions that included at least a case manager, a primary care provider and a mental health specialist who collaborated were eligible for inclusion. Interventions had to target patients with a diagnosis of major depression, minor depression or dysthymia and without comorbid psychoses. Interventions had to be conducted in a high-income country. Patients exposed to the intervention had to be compared to a group who had not been exposed or who had been less exposed. Studies had to report depression outcomes, screening and diagnosis, adherence to treatment or health-related quality of life and functional status.

A wide range of standardised instruments were used to measure depression symptoms. Outcome definitions were reported. Where reported, most participants were white adults (22 to 64 years) or older adults (over 64 years). Most studies included a combination of patients with minor and major depression that had been diagnosed recently or in the past. A few studies reported comorbidities such as cardiac disease, stroke, diabetes and cancer. In collaborative care models, physicians were generally the primary care provider and nurses served as case managers in most studies. Psychiatrists and psychologists generally acted as mental health specialists. Interventions were implemented in a wide range of settings. Most were conducted in USA. The number of studies conducted in an NHS setting was unclear.

The authors did not state how many reviewers selected the studies.

Assessment of study quality

Design quality and threats to the validity of the studies were assessed using standard criteria. Studies were classed as having good (zero to one limitation), fair (two to four limitations) or limited (five or more limitations) quality of execution. Studies found to have limited quality of execution were excluded.

Two reviewers independently assessed study quality. Disagreements were resolved via consensus or with several other reviewers.

Data extraction

Outcome data were extracted to calculate odds ratios (ORs) and standardised mean difference with a correction factor (Hedges’ g). Calculation of 95% confidence intervals (95% CIs) and adjustment for baseline data were performed where possible. Study authors were contacted for missing or inconsistent data.

Several reviewers extracted study data but it was not stated whether this was done in duplicate.

Methods of synthesis

Meta-analyses were conducted using the random-effects model to calculate an overall weighted mean effect estimate (Hedges’ g or odds ratio). Homogeneity was evaluated using Q and Ι² statistics (Ι²≥50% indicated substantial heterogeneity).

Subgroup analyses were conducted to evaluate the effect of several variables (such as type of organisation, type of case manager and collaborative care components) and identify possible sources of heterogeneity. Sensitivity analyses were conducted to evaluate the effect of each individual study on the pooled estimates. Publication bias was assessed using several statistical tools.

Evidence was classed as strong, sufficient, or insufficient on the basis of the number of available studies, suitability of study designs for evaluating effectiveness, quality of execution of studies, consistency of results and effect estimates.

Results of the review

Thirty-two studies were included (number of patients not reported). Most studies (number not reported) were randomised controlled trials (RCTs) with researchers blinded to treatment allocation. Follow-up ranged from less than six months to nine years.

Collaborative care was associated with a significant improvement in depression symptoms (SMD 0.34, 95% CI 0.25 to 0.43; 28 study arms), better adherence (OR 2.22, 95% CI 1.67 to 2.96; 10 study arms) and better response to treatment (OR 1.78, 95% CI 1.42 to 2.23; 14 study arms).

Collaborative care was associated with significantly greater remission before six months (OR 2.37, 95% CI 1.72 to 3.25; five study arms) and after six months (OR 1.74, 95% CI 1.14 to 2.63; nine study arms) and better recovery rates (OR 1.75, 95% CI 1.17 to 2.61; five study arms) and satisfaction with care (SMD 0.39, 95% CI 0.26 to 0.51; 11 arms). All effects were considered to be meaningful and of public health benefit except for quality of life (where only a small effect was observed). The authors stated that substantial heterogeneity (Ι²>50%) was reported for several of the outcomes.

Results of subgroup and sensitivity analyses were reported. No evidence of publication bias was found.

Authors' conclusions

There was robust evidence to show that collaborative care models were effective for treating depressive disorders in a wide range of populations, settings and organisations.

CRD commentary

The review objectives and inclusion criteria were stated clearly. A large number of bibliographic sources were searched, including searches for unpublished studies. Date and language restrictions were applied to the searches so some studies may have been missed. Attempts to minimise error and bias were made when assessing study quality; whether similar steps were made at the study selection and extraction stages of the review was unclear. Individual study details and results of the quality assessment were not reported.

A wide range of instruments were used to measure outcomes and were adjusted using appropriate methods. The choice of a quantitative synthesis appeared appropriate for the outcome on improvement in depression symptoms. A forest plot was reported for this outcome only, which showed a generally consistent effect over a relatively large number of studies. Heterogeneity was explored using appropriate tests and substantial levels were found for several outcomes but detailed results were not reported. Sensitivity analyses suggested that the results of the analysis were robust. The authors interpreted the meaningfulness of the pooled effects within a public health context.

Despite gaps in the reporting of the review, the conclusions appeared to reflect the evidence and are likely to be reliable.

Implications of the review for practice and research

Practice: The authors stated that care should be taken by organisations that wished to implement collaborative care to make sure that training was adequate for case managers, with an emphasis on effective communication among providers.

Research: The authors stated that future research should provide information on the essential training and background required of key members of the collaborative care team, information on optimal frequency and intensity of case management sessions and utility of additional sessions for patients who do not improve. Studies were also needed of collaborative care for children and adolescents, patients of low socioeconomic status and those with comorbid conditions. More research studies that focused on improving depression screening at the primary care level through collaborative care were needed.

Funding

Centre for Disease Control and Prevention, USA.

Bibliographic details

Thota AB, Sipe TA, Byard GJ, Zometa CS, Hahn RA, McKnight-Eily LR, Chapman DP, Abraido-Lanza AF, Pearson JL, Anderson CW, Gelenberg AJ, Hennessy KD, Duffy FF, Vernon-Smiley ME, Nease DE Jr, Williams SP; Community Preventive Services Task Force. Collaborative care to improve the management of depressive disorders: a community guide systematic review and meta-analysis. American Journal of Preventive Medicine 2012; 42(5): 525-538. [PubMed: 22516495]

Original Paper URL

http://www.sciencedirect.com/science/article/pii/S0749379712000761

Other publications of related interest

Jacob V, Chattopadhyay SK, Sipe TA, Thota AB, Byard GJ, Chapman DP; Community Preventive Services Task Force. Economics of collaborative care for management of depressive disorders: a Community Guide systematic review. Am J Prev Med 2012; 42(5): 539-549.

Bower P, Gilbody S, Richards D, Fletcher J, Sutton A. Collaborative care for depression in primary care: making sense of a complex intervention: systematic review and meta-regression. Br J Psychiatry 2006; 189(6): 484-493.

Indexing Status

Subject indexing assigned by NLM

MeSH

Age Factors; Community Health Services /organization & administration; Cooperative Behavior; Depressive Disorder /therapy; Humans; Patient Care Management /organization & administration; Patient Care Team /organization & administration; Patient Compliance; Patient Satisfaction; Primary Health Care /organization & administration; Quality of Life; Sex Factors; Socioeconomic Factors; United States

AccessionNumber

12012022526

Database entry date

30/11/2012

Record Status

This is a critical abstract of a systematic review that meets the criteria for inclusion on DARE. Each critical abstract contains a brief summary of the review methods, results and conclusions followed by a detailed critical assessment on the reliability of the review and the conclusions drawn.