Determinants of Oral Chemotherapy Adherence: A Social Cognitive Perspective

PURPOSEOral anticancer agents (OAAs) have transformed cancer treatment by allowing home-based therapy, but adherence remains suboptimal in real-world practice. Guided by Social Cognitive Theory (SCT), this study examined behavioral, cognitive, and socioenvironmental determinants of OAA adherence. PATIENTS and METHODSWe conducted 36 semi-structured interviews with adult cancer patients receiving OAA monotherapy at an academic medical center, a large urban facility, and a rural facility. Interviews were analyzed using a critical realist approach to thematic analysis, deductively guided by SCT. Themes were organized according to the World Health Organizations (WHO) dimensions of adherence. RESULTSFive interrelated themes shaped adherence across WHO dimensions: "[I feel] very confident...Im staying positive about it": Knowledge, Skills, and Self-Efficacy; "Theyll stop me from speaking": Communication and Trust with Providers; "Were at Their Mercy": Logistical Factors in Prescription Refills and Shipment; "Who can afford that?": Distress Related to High Costs and Insurance Coverage Challenges; and "My wife...knows sometimes I forget": Family and Social Support in OAAs Adherence. These findings reflected SCT constructs including self-efficacy, behavioral capability, reinforcement, observational learning, and reciprocal determinism, highlighting the dynamic interactions among personal, social, and health system factors in adherence behavior. CONCLUSIONOAA adherence is shaped by multilevel determinants that extend beyond individual barriers to include provider communication, system logistics, financial burden, and social support. Interventions to improve adherence should be theory-informed, multidisciplinary, and patient-centered, addressing behavioral, relational, and structural influences simultaneously.