Validity and screening capacity of the FCR-1r for fear of cancer recurrence in long-term colorectal cancer survivors

Existing fear of cancer recurrence (FCR) screening measures is being shortened to facilitate clinical use. This study aimed to evaluate the validity and screening capacity of a single-item FCR screening measure (FCR-1r) in long-term colorectal cancer (CRC) survivors with no recurrence and assess whether it performs as well in older as in younger survivors.All Danish CRC survivors above 18, diagnosed and treated with curative intent between 2014 and 2018, were located through a national patient registry. A questionnaire including the FCR-1r, which measures FCR on a 0-10 visual analog scale, alongside the validated Fear of Cancer Recurrence Inventory Short Form (FCRI-SF) as a reference standard was distributed between November 2021 and May 2023. Screening capacity and cut-offs were evaluated with a receiver-operating characteristic analysis (ROC) in older (≥ 65 years) compared to younger (< 65 years) CRC survivors. Hypotheses regarding associations with other psychological variables were tested as indicators of convergent and divergent validity.Of the CRC survivors, 2,128/4,483 (47.5%) responded; 1,654 (36.9%) questionnaires were eligible for analyses (median age 76 (range 38-98), 47% female). Of the responders, 85.2% were aged ≥ 65. Ninety-two participants (5.6%) reported FCRI-SF scores ≥ 22 indicating clinically significant FCR. A FCR-1r cut-off ≥ 5/10 had 93.5% sensitivity and 80.4% specificity for detecting clinically significant FCR (AUC = 0.93, 95% CI 0.91-0.94) in the overall sample. The discrimination ability was significantly better in older (AUC = 0.93, 95% CI 0.91-0.95) compared to younger (0.87, 95% (0.82-0.92), p = 0.04) CRC survivors. The FCR-1r demonstrated concurrent validity against the FCRI-SF (r = 0.71, p < 0.0001) and convergent validity against the short-versions of the Symptom Checklist-90-R subscales for anxiety (r = 0.38, p < 0.0001), depression (r = 0.27, p < 0.0001), and emotional distress (r = 0.37, p < 0.0001). The FCR-1r correlated weakly with employment status (r = - 0.09, p < 0.0001) and not with marital status (r = 0.01, p = 0.66) indicating divergent validity.The FCR-1r is a valid tool for FCR screening in CRC survivors with excellent ability to discriminate between clinical and non-clinical FCR, particularly in older CRC survivors.