Psychometric Validation and Scale Derivation of the ICIQ-Underactive Bladder Patient Reported Outcome Measure.

Area of Science:

• Urology
• Patient-Reported Outcomes
• Psychometrics

Background:

• Underactive bladder (UAB) significantly impacts quality of life.
• Validated instruments are crucial for assessing UAB symptoms and outcomes.
• The International Consultation on Incontinence Questionnaire-Underactive Bladder (ICIQ-UAB) was developed to address this need.

Purpose of the Study:

• To psychometrically validate the ICIQ-UAB.
• To derive scored domains for symptoms, health-related quality of life (HRQoL), and associated bother.
• To establish the reliability, validity, and responsiveness of the ICIQ-UAB.

Main Methods:

• Phase II RCT administration of the ICIQ-UAB at baseline and 4 weeks.
• Descriptive and exploratory factor analyses (EFAs) for domain derivation.
• Reliability (Cronbach's α), validity (correlations with PROMs), and responsiveness (change in scores) assessed.

Main Results:

• 132 patients with detrusor underactivity enrolled.
• Scored domains derived for 11 symptom items and 7 HRQoL items, including bother.
• ICIQ-UAB demonstrated reliability (Cronbach's α ≥ 0.88), construct validity, and known-groups validity.
• Limited responsiveness observed, potentially due to short trial duration or medication efficacy.

Conclusions:

• The ICIQ-UAB, with its two scored domains and bother items, is reliable, valid, and sensitive to UAB severity.
• The instrument is recommended for researchers and clinicians assessing UAB symptoms and HRQoL.
• Further evaluation of responsiveness may be warranted.