Preliminary Validation of PRISM (Pictorial Representation of Illness and Self Measure) – A Brief Method to Assess Suffering

Background: Alleviation of suffering is widely acknowledged as one of the main goals of medicine. However, no measure to assess this crucial aspect of illness has been developed to date. Aims: To validate PRISM (Pictorial Representation of Illness and Self-Measure) as a simple quantitative method of assessing the perceived burden of suffering due to illness. Methods: Validity and reliability studies to date have involved over 700 patients with a variety of chronic physical illnesses. Results: Reliability of PRISM is good (test-retest reliability r = 0.95; p ≤ 0.001, interrater reliability r = 0.79; p ≤ 0.001). Qualitative data indicate that the interpretation of the PRISM task is not only consistent among patients, but also consistent with that expected from existing literature on suffering. As expected, PRISM shows strong correlations with psychological variables (notably depression and coping resilience) and also correlates with SF-36 subscale scores. Prospective longitudinal data demonstrate that PRISM is sensitive to therapeutic change. It is very acceptable to patients and takes less than 5 min to administer. Conclusion: In the absence of a ‘gold standard’ measure of suffering, our validation data must be interpreted with caution. However, the performance of PRISM is entirely consistent with what would be expected of a measure of suffering, based on current published work.