Study designs of evaluations included in the review
Only randomised controlled trials (RCTs) or controlled trials without randomisation, which were published in English language journals, were considered.
Specific interventions included in the review
PSIs were eligible for inclusion: interpersonal interventions concerned with the provision of information, education or emotional support, together with individual psychological interventions addressing a specific health and social care outcome. The interventions included in the review covered a wide range and were enormously heterogeneous. The reviewers grouped them into group-based interventions, individual-based interventions, service configuration, and technology-based interventions. The full list of interventions was given in the review. The control interventions were conventional care or no support.
Participants included in the review
Studies of informal carers of people living in the community were eligible.
Outcomes assessed in the review
The inclusion criteria for the review specified outcomes of psychological health (e.g. depression, guilt, anger, frustration, rage, hostility, stress, anxiety), physical health and quality of life (including perception of burden). Most of the included studies used measures of perception of burden and psychological morbidity.
How were decisions on the relevance of primary studies made?
The papers were selected according to the pre-specified inclusion criteria, but the authors do not state how many of the reviewers performed the selection.