Identifying cluster subtypes for intentions to have colorectal cancer screening among non-compliant intermediate-risk siblings of individuals with colorectal cancer

Although first-degree relatives of colorectal cancer (CRC) patients diagnosed at an early age are at increased risk for CRC, their compliance with colorectal cancer screening (CRCS) is not high. Relatively little is known about why these intermediate-risk family members do not comply with CRCS. Study aims were to identify subgroups of siblings of individuals diagnosed with CRC prior to age 61 who were not compliant with CRCS using cluster analysis and to identify demographical, medical and attitudinal correlates of cluster membership. A total of 421 siblings completed measures of pros, cons, processes of change, CRCS knowledge, physician and family CRCS support, CRC risk, severity, preventability, curability, closeness with the affected sibling, distress about the sibling's cancer and screening intentions. Three clusters characterized as 'Positive about Screening', 'Uncertain about Screening' and 'Negative about Screening' were identified. External validation revealed that those in the Positive about Screening cluster reported significantly stronger CRCS intentions than those who are Uncertain about Screening and Negative about Screening clusters. Results provide an empirical typology for understanding motivations for CRCS among at-risk family members and may lead to the development of more effective interventions to improve screening uptake.