Chinese Cancer Patients’ Willingness for Phase III Trials: Health Belief Model and Social Support

This study assessed Chinese cancer patients’ willingness to participate in phase III clinical trials of new anti-cancer drugs and examined influencing factors using the Health Belief Model (HBM) and social support. A cross-sectional survey recruited 480 patients from an online community through convenience sampling. Data included demographics, disease and treatment status, HBM constructs (including perceived severity, perceived benefit, perceived barrier, cue to action, self-efficacy), social support (including family’s, friends’, and others’ support), and willingness to participate. Statistical analyses involved factor analysis, reliability testing, correlations, and hierarchical regression. The mean willingness score was 2.883 (range = 1–5). Willingness varied significantly by living arrangements, employment, income, and treatments. Demographics explained 9.8% of the variance, disease and treatment status 12%, and social support 22.4%, with family support as a significant predictor (β = 0.202, p < .001). Incorporating HBM constructs raised the explained variance to 48.2%. Key positive predictors included cues to action (β = 0.251), self-efficacy (β = 0.281), and perceived severity (β = 0.151), while perceived barriers reduced willingness (β = −0.114). Findings suggest Chinese cancer patients show limited willingness to join phase III trials, although it should be generalized cautiously, considering the non-representative nature of the online sample. Enhancing family support and targeting self-efficacy and external motivators may improve engagement, supporting the utility of the HBM framework.