Protocol and registration

The review protocol was registered with PROSPERO (registration: CRD42015024618), and published in BioMed Central Systematic Reviews [12] in accordance with the criteria in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement for systematic reviews [13].

Eligibility criteria

The following criteria outline the eligibility of studies that were included in the review.

Types of studies

Studies were eligible if they were RCTs of community-based interventions coordinating care in dementia. We excluded non-randomised experimental studies such as before-and-after or quasi-experimental studies.

Types of participant

We included studies that involved participants with a dementia diagnosis of any type who were living at home, with no restrictions on age or gender. We excluded studies of individuals who did not have a formal diagnosis of dementia or had self-defined as having dementia due to the uncertainty of diagnosis in such participants. Additionally, we excluded studies that focused solely on informal caregivers of individuals with dementia which did not include a focus on increased care coordination or improved outcomes for individuals with dementia.

Types of intervention

We included interventions that were delivered by a single, identified professional who took responsibility for the provision and management of care. The main focus of their role was described in the study report as planning, facilitating and/or coordinating care through assessments and proactive follow-ups.

Control

Comparators included ‘usual care’, standard community treatment, alternative dementia care interventions or waiting-list controls.

Setting

We included studies of interventions that were based in the community. We excluded studies based in hospitals or nursing/residential homes, and those that involved changes made to healthcare systems or application of guidelines alone.

Types of outcome measures

We considered all available binary and continuous outcome measures related to individuals with dementia and/or their informal caregiver.

Date, language and location

No restrictions were placed on date, language or study location.

Information sources

Electronic searches

The following four electronic databases were searched from date of inception to June 2015, with the search syntax being modified appropriately for the individual database: MEDLINE (OvidSP), The Cochrane Library, EMBASE and PsycINFO. Electronic searches were updated in April 2017.

Additional resources

We searched four additional databases for unpublished studies; the Health Management Information Consortium (HMIC), Social Policy and Practice (SPP), ProQuest and the International Clinical Trials Registry Platform (ICTRP). Backward and forward citation searches were completed on included studies and relevant systematic reviews identified in screening.

Search

A comprehensive search strategy was developed through consultation with an information specialist (DM) and information on intervention terminology from a prior scoping review of the literature. The search based on the outlined eligibility criteria used a combination of controlled vocabulary specific to the individual database (e.g. MEDLINE Medical Subject Headings (MeSH terms)) and free text terms. A master search strategy can be found in Additional file 1.

Study selection

Data management

All references were managed in EndNote X7.0.2. Titles and abstracts of studies identified in the initial search were imported into EndNote and duplicates were removed, then full texts of potentially relevant papers were imported for further screening.

Screening

Two independent reviewers (AB, RW) conducted an initial screening of titles and abstracts followed by a screening of potential relevant full texts guided by inclusion criteria. A third reviewer (CD) was available for any screening disagreement.

Data extraction

A bespoke data extraction sheet designed using Microsoft Office Excel was piloted by one reviewer (AB) on three RCTs and modified in light of piloting. Data were extracted on study design, participant characteristics, methodology, intervention characteristics, comparator group(s) and outcome measures.

Data were also extracted on intervention components identified as potentially important in influencing treatment effects, based on the results of our recent review of qualitative evidence [11]. Informed by our review of qualitative studies the following intervention characteristics were identified for subgroup analysis:

1. Case manager base – i.e. the working location of the case manager, either in community or non-community (e.g. primary care) settings 2. Case manager professional background – nursing background or non-nursing 3. Case manager training – specifically trained for the case manager role or not 4. Contact frequency – how often the case manager was in contact, grouped as those with low contact frequency (less than or equal to the median across studies of 14.4 contacts per 12 months) and high contact frequency (more than 14.4 contacts per 12 months). 5. Contact type – mode of contact (i.e. telephone, face-to-face or written) used to communicate with individuals with dementia and their caregivers 6. Supervision – whether or not the case manager had been assigned a mentor or supervisor during the intervention 7. Workload – case manager caseload, divided at mean number of patients per case manager across studies (51.1), into those with high caseload (more than 50 patients) and low caseload (less than or equal to 50 patients).

Results of studies represented in multiple papers are included in the review once to avoid double counting. For trials with more than one associated paper, the primary paper has been cited as the main reference though data were extracted from all available papers. We approached authors via email to obtain missing data. Six missing standard deviations (SD) were calculated from standard errors of the mean (SEM) and two missing SDs were obtained from other studies.

Risk of bias

The Critical Appraisal Skills Programme (CASP) RCT appraisal tool [14] was used to assess the quality of included studies. The checklist includes 11 questions covering rigour, research methods, relevance and research integrity. Two independent reviewers (AB, RW) assessed the quality of included trials, and disagreement was resolved through discussion.

Method of analysis

Descriptive statistics were used to summarise main study characteristics and the risk of bias.

Meta-analysis

Random-effects meta-analyses of RCTs were conducted using Review Manager 5.3. Random-effects meta-analysis was selected over fixed-effect meta-analysis because of the methodological heterogeneity across studies. For continuous outcomes, standardised mean differences (SMD) were pooled, except when change scores and final scores were combined in which case the mean difference (MD) was pooled. For binary outcomes, odds ratios (OR) were pooled. For the purpose of this meta-analysis, where specific outcomes were measured across multiple time points, the result nearest the median time point for that outcome was used. Heterogeneity across studies was quantified using the I squared (I [2]) statistic (the percentage of variation across studies that is due to between-study heterogeneity as opposed to chance) [15].

Subgroup analysis

Trials were grouped based on the presence or absence of intervention components identified, as outlined above. Intervention effects were estimated within subgroups and compared across subgroups to identify components for which the size of the effect depends on whether they are present; in other words, to identify components that modify the intervention effects.