To examine the mediating role of pain acceptance (PAcc) between fear of negative evaluation (FNE) and activity avoidance (AV) at different levels of positive affect (PA) (moderator) among women diagnosed with fibromyalgia (FM) (moderate mediation model). This study was cross-sectional in design. A convenience sample of women with FM (n = 231) completed measures of pain severity, FNE, PAcc, AV, and PA. A simple mediation model and a moderate mediation model was constructed and analyzed using the SPSS macro-PROCESS. First, PAcc mediated the effect of FNE on AV (β = .02, SE = 0.008; [95% CI [0.0075, 0.0394]). Second, a mediated effect of PAcc between FNE and AV moderated by PA at medium and high levels of PA were found (m: 0.23; β = -.22, p = .0006; h: 9.59; β = -.34, p = .0002. Future work should seek to validate study findings in diverse samples of FM patients. Additionally, future work should explore how FM self-management interventions that include PAcc can promote increased activity among women suffering from FM with medium to high levels of PA.
Keywords: activity avoidance; fear of negative evaluation; fibromyalgia; pain acceptance; positive affect.