ConquerFear-HK: A Randomized Controlled Trial of a Metacognition-Based, Manualized Intervention for Fear of Cancer...

Introduction: Fear of cancer recurrence (FCR) is a prominent clinical issue among cancer survivors. This study evaluated the effectiveness of the culturally adapted ConquerFear-HK intervention in reducing FCR among Chinese cancer survivors, compared to standard survivorship care.

This assessor-masked, two-arm parallel randomized controlled trial, was conducted from June 2021 to February 2024. Cantonese- or Mandarin-speaking Chinese cancer survivors scoring ≥13 on the Fear of Cancer Recurrence Inventory Short Form (FCRI-SF) were randomized to either ConquerFear-HK, focusing on attention training, metacognition modification, acceptance, appropriate monitoring behaviour, and goal setting or active control providing standardized, multidisciplinary survivorship care. Primary outcome was changes in FCR assessed by FCRI at prior randomization, immediately post-intervention (T1), 3 months (T2), and 6 months (T3) post-intervention. Intention-to-treat analyses using linear mixed modelling compared outcome changes across time points. This trial was registered at ClinicalTrials.gov (NCT04568226).

Of the 175/220 (79.5%) participants recruited, 89 were randomized to ConquerFear-HK and 86 to control. Significant greater FCRI reductions were observed in ConquerFear-HK at T1 (mean difference = -10.66; 95% CI:-20.15, -1.16) and T2 (mean difference = -12.00; 95% CI:-21.90, -2.11) vs. the control (g = 0.33-0.36). No significant between-group differences were found at T3.

ConquerFear-HK demonstrates promising short-term (3-month) improvements in FCR among Chinese cancer survivors; however, no sustained benefits were found at 6 months. Possible explanations include the high attrition at 6-month follow-up, a potential early ceiling effect, unconscious therapist bias, or an accelerated adaptation effect in the intervention arm that was achieved later by the control group.