The development and validation of the Worries About Recurrence or Progression Scale (WARPS)

Objectives: Worry about recurrence or progression is a common concern among people with chronic physical illnesses. Although there are options to measure the fear of cancer recurrence and other illness-specific measures, there is only one transdiagnostic measure of fear of progression, which does not assess the fear of recurrence or relapse.Design: A multi-phase study outlining the development and validation of a novel transdiagnostic measure of fear of recurrence or progression, the Worries About Recurrence and Progression Scale (WARPS).Method: From a prior systematic review, we used quotes from people with lived experience to generate 55 items. Next, we piloted the items with 10 people with a range of chronic conditions, leading to a final total of 57 items. We then recruited four groups of people with cardiac disease, rheumatic disease, diabetes and respiratory disease (n = 804). An exploratory factor analysis in a randomly split sample resulted in an 18 item, single factor scale. We then performed confirmatory factor analysis on these 18 items in the remaining sample.Results: The 18-item WARPS demonstrated good construct validity, internal consistency and test-retest reliability. Specifically, the WARPS was strongly correlated with the Fear of Progression Questionnaire, and with illness-specific fears. Significant, moderate correlations were observed with depression, anxiety, stress, and death anxiety. The WARPS demonstrated the validity and reliability amongst people with four of the most common chronic conditions and the factor structure was invariant across genders.Conclusion: The WARPS is a valid and reliable tool to measure transdiagnostic worries about recurrence and progression.