Although the articles reviewed revealed four groups of symptoms that tended to cluster, there is limited consistency in the way in which SCs and variables associated with them are identified. This is largely due to a lack of agreement about a robust, clinically relevant definition of SCs. Future research should focus on patients' subjective experience of SCs to inform a clinically relevant definition of SCs and how they are managed over time.

Findings highlight the need to integrate patient/family education within improved communication, individualize care, use more nonpharmacological strategies, empower patients/families to self-manage pain, and reorganize multidisciplinary roles around patient-centered care and outcomes. These conclusions require validation via consensus and intervention trials.

Provision of a video and/or booklet for people with cancer pain was a feasible and effective adjunct to the management of cancer pain.

Patient education is effective in reducing cancer pain and should be standard practice in all settings. For optimal results, patient education should be integrated with other strategies for implementing evidence-based, person-centered care and overcoming barriers at the levels of patient, provider, and health system.

Purpose: To investigate the consistency of symptom cluster composition in advanced cancer patients using different statistical methodologies for all patients across five primary cancer sites, and to examine which clusters predict functional status, a global assessment of health and global quality of life.Methods: Principal components analysis and exploratory factor analysis (with different rotation and factor selection methods) and hierarchical cluster analysis (with different linkage and similarity measures) were used on a dataset of 1562 advanced cancer patients who completed the EORTC QLQ-C30.Results: Four clusters consistently formed for many of the methods and cancer sites: tenseworry-irritable-depressed (emotional cluster); fatigue-pain; nausea-vomiting; and concentrationmemory (cognitive cluster). The emotional cluster was a stronger predictor of overall quality of life than the other clusters. Fatigue-pain was a stronger predictor of overall health than the other clusters. The cognitive cluster and fatigue-pain predicted physical functioning, role functioning, and social functioning. Conclusions:The four identified symptom clusters were consistent across statistical methods and cancer types, although there were some noteworthy differences. Statistical derivation of symptom clusters is in need of greater methodological guidance. A psychosocial pathway in the management of symptom clusters may improve quality of life. Biological mechanisms underpinning symptom clusters need to be delineated by future research. A framework for evidence-based screening, assessment, treatment, and follow-up of symptom clusters in advanced cancer is essential.Statistical methods for symptom clusters in advanced cancer