5O-1 VALIDATING THE BLADDER UTILITY SYMPTOM SCALE (BUSS): A MULTIATTRIBUTE HEALTH STATE CLASSIFICATION SYSTEM FOR ALL PATIENTS WITH BLADDER CANCER

Wednesday, October 26, 2016: 10:00 AM
Bayshore Ballroom Salon F, Lobby Level (Westin Bayshore Vancouver)

Kirstin E Boehme, MSc1, Nathan Perlis, MD, MSc2, Munir Jamal, MD3, Karen E Bremner, BSc4, Shabbir MH Alibhai, MD, MSc5, Antonio Finelli, MD, MSc2, Paul Ritvo, PhD6, Murray D. Krahn, MD, MSc7 and Girish Kulkarni, MD, PhD2, (1)University Health Network, Toronto General Research Institute, THETA Collaborative, Toronto, ON, Canada, (2)University of Toronto and University Health Network, Division of Urology, Department of Surgery, Toronto, ON, Canada, (3)Trillium Health Partners, Mississauga, ON, Canada, (4)Toronto Health Economics and Technology Assessment (THETA) Collaborative, Toronto, ON, Canada, (5)University of Toronto and University Health Network, Toronto General Research Institute, Division of Support, Systems, and Outcomes, Toronto, ON, Canada, (6)York University and Cancer Care Ontario, Toronto, ON, Canada, (7)University of Toronto and University Health Network, Toronto General Research Institute, Toronto Health Economics and Technology Assessment (THETA) Collaborative, Toronto, ON, Canada
Purpose: Bladder cancer (BCa) patients face difficult decisions when choosing treatment. The inclusion of patients’ perspectives on tradeoffs between cancer control and health-related quality of life (HRQOL) is necessary when deciding upon optimal treatment plans. Research regarding BCa outcomes and patient preferences, however, is limited. We recently developed a multi-attribute health state classification system called the BUSS-P (Bladder Utility Symptom Scale Psychometric) using rigorous psychometric methodology. Our goal herein was to test the validity and reliability of the instrument to measure global, preference-based HRQOL among BCa patients.

Methods: To determine BUSS-P validation and reliability and to ensure generalizability, multi-centre field testing was conducted at an academic (University Health Network, Toronto, ON) and a community (Trillium Health Partners, Mississauga, ON) hospital. Purposive sampling was used to accrue 112 BCa patients with varying disease severity and treatment history. Patients completed the BUSS-P and five other HRQOL and utility instruments (FACT-Bl, BCI, EQ-5D, SF-36, TTO). Whole and subscale Spearman’s rank correlations (rs), as well as comparisons of BUSS-P scores across known-groups were used to assess construct validity. Reliability was assessed at two time-points, four weeks apart.

Results: The BUSS-P was found to have high whole-scale correlations with the FACT-Bl (rs=0.82, p<0.0001), the EQ-5D (rs=0.65, p<0.0001), and the SF-36v2 (PCS rs=0.63, p<0.0001; MCS rs=0.65, p<0.0001). Likewise, high subscale correlations were observed between the BUSS-P and the EQ-5D (emotional wellbeing: rs=0.69, p<0.0001), the FACT-Bl (physical wellbeing: rs=-0.70, p<0.0001), and the BCI (urinary issues: rs=-0.62, p<0.0001). Median BUSS-P scores (M) were found to be significantly different (Kruskal-Wallis p=0.0008) across patients with differing disease severity: non-muscle invasive BC (M=85.0), cystectomy (M=80.0), and metastatic BC patients (M=67.50). Similarly, significant differences (p<0.0001) were noted between the median BUSS-P scores of patients with low comorbidity scores (Charlson Index <4, M=85.0) versus high comorbidity scores (Charlson Index ≥4, M=69.17); a finding that persists when cancer is excluded as a comorbid condition (Charlson Index <2 vs. ≥2, p=0.036). Lastly, excellent agreement was observed between BUSS-P scores at test and retest (ICC=0.79).

Conclusions: These results indicate that the BUSS-P is a valid and reliable instrument to measure HRQOL among all BCa patients (localized to metastatic disease). Future work collecting patient- and community member-generated utility weights to convert the questionnaire into a disease-specific utility instrument is under way.

See more of: ORAL ABSTRACTS: MEASURING ECONOMIC AND HEALTH OUTCOMES

See more of: 38th Annual North American Meeting of the Society for Medical Decision Making