OBJECTIVES: Previous studies applied the time trade-off (TTO) to elicit utility values in psoriasis; however, its validity against the most commonly used outcome measures in dermatology such as Dermatology Life Quality Index (DLQI) and Psoriasis Area and Severity Index (PASI) has not yet been confirmed. Thus, we aim to assess the construct validity of the TTO in adult patients with psoriasis. METHODS: A cross-sectional survey was carried out at an academic dermatology clinic in Hungary. Psoriasis patients aged ≥18 years, regardless of severity, were eligible to participate in the study. TTO utilities were obtained via a self-completion booklet using a 10-year time frame and top-down titration. The DLQI was used to assess health-related quality of life and PASI to evaluate disease severity. Convergent validity was examined using Spearman’s correlations. Known-groups validity was tested with regard to clinical subtypes of psoriasis and treatment groups. RESULTS: Altogether 238 patients with psoriasis completed the survey with a mean age of 47±15 years, and 63% were males. Overall, 37% received biological therapy, 22% systemic non-biological therapy, 38% topical and 3% none. Mean DLQI and PASI scores were 7.13±7.36 and 8.68±9.19, respectively. The mean TTO utility in the sample was 0.91±0.16. Significant inverse correlations were observed between TTO utilities and DLQI and PASI scores (Spearman’s rho -0.406 and -0.290; p<0.001). The TTO failed to discriminate between known-groups based on clinical subtypes with the exception of scalp psoriasis. TTO utility scores of patients treated either by biologics (0.93±0.15) or by systemic non-biologics (0.91±0.18) were significantly higher compared to those treated topically or none (0.89±0.16; p<0.05). CONCLUSIONS: The self-completion method of the 10-year TTO demonstrated low to moderate convergent validity and a poor known-groups validity in psoriasis patients. Based on our findings, the application of the 10-year TTO to derive utilities is not recommended in randomized controlled trials of psoriasis therapies.