Purpose: We developed the ureteral stent symptom questionnaire (USSQ), a psychometrically valid measure to evaluate symptoms and impact on quality of life of ureteral stents.
Materials and methods: A total of 309 patients were asked to participate during different phases of our study. In phase 1 a structured literature search, 9 patient interviews and studies of 90 patients using existing instruments formed the foundation for the initial draft of our new questionnaire. In phase 2 the USSQ was pilot tested, reviewed by experts and field tested in 40 patients to produce a final 38-item draft. In phase 3 formal validation studies were performed in 55 patients to assess validity, reliability and sensitivity to change. Discriminant validation was performed by administering the questionnaire to 3 groups of patients without stents.
Results: The final draft addressed various domains of health (6 sections and 38 items) affected by stents covering urinary symptoms, pain, general health, work performance, sexual matters and additional problems. The validation studies showed the questionnaire to be internally consistent (Cronbach's alpha > 0.7) with good test-retest reliability (Pearson's coefficient > 0.84). The questionnaire demonstrated good construct validity and sensitivity to change shown by significant changes in the score with and after removal of stents. The new USSQ discriminated patients with stents from healthy controls (p < 0.001) and patients with urinary calculi without stents and lower urinary tract symptoms.
Conclusions: Indwelling ureteral stents have a significant impact on health related quality of life. The new USSQ is a valid and reliable instrument that is expected to become a standard outcome measure to evaluate the impact and compare different types of stents.