Psychosocial functioning and risk factors among siblings of children with cancer: An updated systematic review

Siblings' psychosocial adjustment to childhood cancer is poorly understood. This systematic review summarizes findings and limitations of the sibling literature since 2008, provides clinical recommendations, and offers future research directions.

MEDLINE/Pubmed, Cumulative Index to Nursing and Allied Health Literature, and PsycINFO were searched for articles related to siblings, psychosocial functioning, and pediatric cancer. After systematic screening, studies meeting inclusion criteria were rated for scientific merit, and findings were extracted and synthesized. In total, 102 studies were included (63 quantitative, 35 qualitative, 4 mixed-methods).

Methodological limitations are common. Mean levels of anxiety, depression, and general adjustment are similar across siblings and comparisons, but symptoms of cancer-related posttraumatic stress are prevalent. School-aged siblings display poorer academic functioning and more absenteeism but similar peer relationships as peers. Quality of life findings are mixed. Adult siblings engage in higher levels of risky health behaviors and may have poorer health outcomes than comparisons. Risk factors for poor sibling adjustment include lower social support, poorer family functioning, lower income, non-White race, and shorter time since diagnosis, but findings are inconsistent. Qualitative themes include siblings' maturity, compassion, and autonomy, but also strong negative emotions, uncertainty, family disruptions, limited parental support, school problems, altered friendships, and unmet needs.

Despite methodological limitations, research indicates a strong need for sibling support. Clinical recommendations include identifying at-risk siblings and developing interventions to facilitate family communication and increase siblings' social support, cancer-related knowledge, and treatment involvement. Future longitudinal studies focusing on mechanisms and moderators of siblings' adjustment would inform timing and targets of psychosocial care.