BACKGROUND: Chronic non-cancer pain in childhood is widespread, affecting 20% to 35% of children and young people worldwide. For a sizeable number of children, chronic non-cancer pain has considerable negative impacts on their lives and quality of life, and leads to increased use of healthcare services and medication. In many countries, there are few services for managing children's chronic non-cancer pain, with many services being inadequate. Fourteen Cochrane Reviews assessing the effects of pharmacological, psychological, psychosocial, dietary or physical activity interventions for managing children's chronic non-cancer pain identified a lack of high-quality evidence to inform pain management. To design and deliver services and interventions that meet the needs of patients and their families, we need to understand how children with chronic non-cancer pain and their families experience pain, their views of services and treatments for chronic pain, and which outcomes are important to them.

OBJECTIVES: 1. To synthesise qualitative studies that examine the experiences and perceptions of children with chronic non-cancer pain and their families regarding chronic non-cancer pain, treatments and services to inform the design and delivery of health and social care services, interventions and future research. 2. To explore whether our review findings help to explain the results of Cochrane Reviews of intervention effects of treatments for children's chronic non-cancer pain. 3. To determine if programme theories and outcomes of interventions match children and their families' views of desired treatments and outcomes. 4. To use our findings to inform the selection and design of patient-reported outcome measures for use in chronic non-cancer pain studies and interventions and care provision to children and their families. The review questions are: 1. How do children with chronic non-cancer pain and their families conceptualise chronic pain? 2. How do children with chronic non-cancer pain and their families live with chronic pain? 3. What do children with chronic non-cancer pain and their families think of how health and social care services respond to and manage their child's chronic pain? 4. What do children with chronic non-cancer pain and their families conceptualise as 'good' chronic pain management and what do they want to achieve from chronic pain management interventions and services?

SEARCH METHODS: Review strategy: we comprehensively searched 12 bibliographic databases including MEDLINE, CINAHL, PsycInfo and grey literature sources, and conducted supplementary searches in 2020. We updated the database searches in September 2022.

SELECTION CRITERIA: To identify published and unpublished qualitative research with children aged 3 months to 18 years with chronic non-cancer pain and their families focusing on their perceptions, experiences and views of chronic pain, services and treatments. The final inclusion criteria were agreed with a patient and public involvement group of children and young people with chronic non-cancer pain and their families.

DATA COLLECTION AND ANALYSIS: We conducted a qualitative evidence synthesis using meta-ethnography, a seven-phase, systematic, interpretive, inductive methodology that takes into account the contexts and meanings of the original studies. We assessed the richness of eligible studies and purposively sampled rich studies ensuring they addressed the review questions. Cochrane Qualitative Methods Implementation Group guidance guided sampling. We assessed the methodological limitations of studies using the Critical Appraisal Skills Programme tool. We extracted data on study aims, focus, characteristics and conceptual findings from study reports using NVivo software. We compared these study data to determine how the studies related to one another and grouped studies by pain conditions for synthesis. We used meta-ethnography to synthesise each group of studies separately before synthesising them all together. Analysis and interpretation of studies involved children with chronic non-cancer pain and their families and has resulted in theory to inform service design and delivery. Sampling, organising studies for synthesis, and analysis and interpretation involved our patient and public involvement group who contributed throughout the conduct of the review. We used the GRADE-CERQual (Confidence in the Evidence from Reviews of Qualitative research) approach to assess our confidence in each review finding. We used a matrix approach to integrate our findings with existing Cochrane Reviews on treatment effectiveness for children's chronic non-cancer pain.

MAIN RESULTS: We synthesised 43 studies sampled from 170 eligible studies reported in 182 publications. Included studies involved 633 participants. GRADE-CERQual assessments of findings were mostly high (n = 21, 58%) or moderate (n = 12, 33%) confidence with three (8%) low or very low confidence. Poorly managed, moderate or severe chronic non-cancer pain had profound adverse impacts on family dynamics and relationships; family members' emotions, well-being, autonomy and sense of self-identity; parenting strategies; friendships and socialising; children's education and future employment prospects; and parental employment. Most children and parents understood chronic non-cancer pain as having an underlying biological cause and wanted curative treatment. However, families had difficulties seeking and obtaining support from health services to manage their child's pain and its impacts. Children and parents felt that healthcare professionals did not always listen to their experiences and expertise, or believe the child's pain. Some families repeatedly visited health services seeking a diagnosis and cure. Over time, some children and families gave up hope of effective treatment. Outcomes measured within trials and Cochrane Reviews of intervention effects did not include some outcomes of importance to children and families, including impacts of pain on the whole family and absence of pain. Cochrane Reviews have mainly neglected a holistic biopsychosocial approach, which specifies the interrelatedness of biological, psychological and social aspects of illness, when selecting outcome measures and considering how chronic pain management interventions work.

AUTHORS' CONCLUSIONS: We had high or moderate confidence in the evidence contributing to most review findings. Further research, especially into families' experiences of treatments and services, could strengthen the evidence for low or very low confidence findings. Future research should also explore families' experiences in low- to middle-income contexts; of pain treatments including opioid use in children, which remains controversial; and of social care services. We need development and testing of family-centred interventions and services acceptable to families. Future trials of children's chronic non-cancer pain interventions should include family-centred outcomes.