Longitudinal examination of the health action process approach in predicting psychosocial support service use among patients with cancer

Background: Many patients with cancer do not use psychosocial support services even when they experience concerns. This study aimed to develop scales of the Health Action Process Approach (HAPA) constructs related to psychosocial support service utilization and to longitudinally examine the applicability of this framework for predicting service use among patients with cancer. Methods: A two-wave web survey was conducted among patients diagnosed with cancer. At Time 1, demographic and treatment information, the HAPA constructs (positive and negative outcome expectancies, self-efficacy, risk perception, intention, and action and coping planning), and psychological distress were assessed. The utilization of psychosocial support services was measured at Times 1 and 2. Results: Data from 510 participants were analyzed. Factor analyses showed that outcome expectancies comprised two factors (positive/negative); risk perception, self-efficacy, and intention each formed a single factor; and planning comprised two factors (action/coping). In the structural equation model predicting Time 2 utilization, the direct path from intention to utilization was not significant, whereas the indirect pathway through action and coping planning was significant ( n = 477). Conclusions: The HAPA framework appears to be applicable for predicting the utilization of psychosocial support services among patients with cancer. Our findings suggest that, in addition to enhancing intention, supporting concrete planning, particularly coping planning, is essential for promoting service use. Further clinical examination and intervention studies based on the HAPA framework are needed.