Hypothesis / aims of study
Patient-Reported Outcome Measures (PROMs) are playing an increasingly pivotal role in the evaluation of therapeutic outcomes. They offer valuable insights into patients’ experiences and needs, yet they are often developed without direct patient involvement. The Urethral Stricture Symptom and Impact Measure (USSIM) is a set of PROMs developed in the United States in close collaboration with patients to assess the outcomes and impact of urethral stricture treatment. Currently, no validated instrument exists in the Netherlands to objectively evaluate treatment outcomes for urethral strictures. The development of a Dutch version could significantly contribute to the standardization and patient-centeredness of care. This study represents the initial steps towards the validation of the Dutch version: the D(utch)USSIM
Study design, materials and methods
Linguistic validation was performed in accordance with established standardized guidelines. The original English version (USSIM) was translated into Dutch by two professional translators, both of whom are native Dutch speakers. Any discrepancies identified were resolved through discussions with the translators, two urologists, and the researcher. Subsequently, the questionnaire was retranslated into English by a professional translator to ensure content consistency and accuracy.
In spite of the extensive validation of the original version, the resulting DUSSIM was administered in interview form (T0) to 14 men with a treated urethral stricture (US, median age 56 years (22-78)). The US group consisted of patients who visited the Urology outpatient clinic between November 2024 and February 2025 for urethral strictures and had sufficient proficiency in the Dutch language. The Reference group consisted of 15 patients from the Maxillofacial Surgery outpatient clinic, all without micturition problems (Reference, median age 46 years (19-69)). The US group completed the DUSSIM again two weeks later (T2). Exploratory statistics, including the Wilcoxon Rank Sum and Signed Rank tests (for small sample sizes and non-normal distributions, R version 4.4.3), were applied to confirm the validation outcomes of the original version.
Results
The official steps taken towards the Dutch translation did not lead to any significant linguistic or substantive alterations. The participants understood the DUSSIM well, with comments on question 10 (negatively formulated) and question 12 (somewhat difficult). In the US-group, 6 out of 14 felt a question on self-catheterization was missing. For all questions, subdomains, and the total score, responses at T0 and T2 in the US group showed no significant difference (hypothesis-rejecting threshold: p=0.05), confirming the already in the original rigorously tested consistency and reproducibility. As hypothesized, the DUSSIM successfully differentiated between the US group and the reference group (threshold the same), with the exception of the questions on sexuality and urination in public. See Table.
Interpretation of results
Our study elegantly shows the importance of a rigorously constructed and validated questionnaire with patient input at each step. Not only proved the translation into Dutch therefor without significant difficulties, but in our interviews the questions proved easily understood as well. Besides, already in our small interview groups consistency, reproducibility and acceptable discrimination could be established. The availability of a patient co-constructed PROMs on urethral strictures in the Dutch patient’s own language thus comes one step closer.