Abstract
OBJECTIVE: To examine actor-partner interdependence between fear-of-progression (FoP) and global quality of life (QOL) in Thai gynecologic-cancer survivor-caregiver dyads. METHODS: A cross-sectional study recruited 300 survivor-caregiver pairs from tertiary oncology centers in Bangkok, Thailand. Survivors were ≥6 months post-treatment for cervical, ovarian, or uterine cancer. Dyads completed the Thai Fear of Progression Questionnaire Short Form and the WHOQOL-BREF. Actor-Partner Interdependence Models (APIM) were estimated with structural equation modeling, treating dyad members as distinguishable (patient vs. caregiver). Models controlled for age, time since diagnosis, and comorbidity count. RESULTS: Mean FoP scores were 27.4 ± 9.3 for survivors and 26.8 ± 8.8 for caregivers; mean QOL totals were 88.9 ± 12.1 and 90.2 ± 12.4, respectively. FoP levels were moderately correlated within dyads (r = 0.37, p < 0.001). In APIM, higher FoP predicted poorer QOL for the same person (actor effects: β = -0.38, p < 0.001 for survivors; β = -0.25, p = 0.001 for caregivers). Partner effects were small and non-significant (caregiver FoP → survivor QOL: β = -0.03, p = 0.46; survivor FoP → caregiver QOL: β = -0.05, p = 0.28). Goodness-of-fit indices supported the actor-only pattern (χ(2) = 3.4, df = 4, p = 0.49; RMSEA = 0.00; CFI = 1.00). CONCLUSION: Among Thai gynecologic-cancer dyads, fear-of-progression erodes the individual's own quality of life but does not appear to does not appear to exert a cross-partner influence. Psycho-oncology programs should therefore screen and treat FoP in both survivors and caregivers, yet expect QOL gains to arise chiefly from direct, rather than cross-partner, relief of fear. Because the design was cross-sectional, temporal ordering cannot be inferred; FoP-QOL associations may be bidirectional (e.g., poorer QOL amplifying FoP and vice versa). Longitudinal, multi-wave APIM is needed to establish directionality. Future work should test domain-level QOL outcomes and longitudinal APIM to determine whether subtle cross-partner effects emerge in specific life domains.