Remarks y Carers were defined as relatives or friends who provide informal and regular care/support to someone with severe mental illness. y Interventions were included in the evidence review if they were provided to the carer alone or a family member (i.e. in the absence of the person with psychosis or bipolar disorder) and if they aimed to improve the carer’s experience in terms of quality of life, personal burden (subjective/objective), depressive symptoms and/or well-being. y The term “psychosocial intervention” is used loosely in research. Interventions are rarely manualized and often do not fall into mutually exclusive categories. The psychosocial interventions described feature common skills including problem-solving techniques, cognitive-behavioural techniques, teaching of coping strategies and communication skills. y Psychoeducation refers to educational programmes with psychological or psychotherapeutic components that provide standardized information and focus on increasing carers’ knowledge of the condition and developing specific coping skills to deal with caregiving challenges. They may be delivered individually or in group settings if the therapeutic components are adapted for delivery in a structured psychoeducational format (Cheng et al.,

• 2020)(190). y The choice of psychosocial intervention format largely depends on available resources in the health system as well as individual preferences.

Implementation considerations y Psychosocial interventions can be delivered effectively in non-specialized health-care settings, as well as in other settings including specialized mental health care and social care. y Integrating the provision of psychosocial interventions for carers into primary care provides many advantages, including more holistic support of carers as well as the person with schizophrenia/ psychosis/schizophrenia spectrum disorder and bipolar disorder, opportunities for reducing the stigma of mental health problems and reduced costs. y Face-to-face psychosocial interventions delivered by service providers is human resource-intensive as they require substantial provider time, training and supervision. y Unguided psychosocial interventions can be delivered without any therapist/service provider support, so they can be less resource intensive and can be used in non-specialized health-care settings if there are insufficient human resources for face-toface/guided psychosocial interventions. y Country adaptation and translation of training materials and tools for the provision of psychosocial interventions is essential.