Subjective Well-being as an Indicator of Patient-relevant Treatment Benefit: Validation of a Simplified 'Day Reconstruction Method' Using the Example of Psoriasis

• Applicant: Privatdozentin Dr. Christine Blome
• Subject Area: Personality Psychology, Clinical and Medical Psychology, Methodology ; Dermatology
• Term: from 2015 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 272472126

The aim of this project is to validate a new method for measuring patient benefit from medical treatments. The method named "Daily Experience Sampling Questionnaire" (DESQ) assesses the patients' subjective well-being at randomly selected moments in everyday life. Currently treatment benefit is usually determined by patients retrospectively rating their impairments due to the disease, for example by referring to the last week (concept of health-related quality of life). This retrospective measurement can be biased since the patients' recall of how they felt a week ago often turns out to be unreliable and also distorted by the mental focus on their health situation. It is expected that the DESQ will eliminate a great part of this bias. The DESQ combines features of 2 existing methods for measuring subjective well-being called "experience sampling" and "day reconstruction method". Compared to these methods, the DESQ will be less time-consuming to conduct and therefore more cost-effective to use. The DESQ has already been pilot tested in patients with psoriasis and in healthy persons. In this project, 120 patients with psoriasis and 120 healthy persons will evaluate their well-being by filling out the DESQ for three consecutive weeks. During this period, the groups will also be asked to evaluate their well-being by applying the method of experience sampling (the current gold standard of measuring subjective well-being). Health-related quality of life (which is the current standard indicator of treatment benefit) will also be assessed. The data of (a) the DESQ and (b) the experience sampling method for each week will be transformed into ratio-scaled index values on subjective well-being. The DESQ will be tested for criterion validity by analysing its concordance with the experience sampling method. In addition, its association to health-related quality of life will be determined. Further research questions include the instrument's sensitivity to change and possible reactivity effects (i.e., an effect of the measurement itself resulting in biased values). If the DESQ proves to be valid and feasible, future clinical and health economic studies may use it to determine patient benefit from medical treatments.

• DFG Programme: Research Grants
• Co-Investigator: Professor Dr. Matthias Augustin