Validation of the BC-Brain Patient Reported Outcome Questionnaire for Patients with Brain Metastases Treated with Radiotherapy

Abstract

<h3>Purpose/Objective(s)</h3> The BC-brain questionnaire was developed by BC Cancer to detect health problems in patients with central nervous system (CNS) tumors in routine clinical care, treated with radiotherapy (RT), as part of the Prospective Outcomes and Support Initiative (POSI). This study aimed to present and validate the BC-brain questionnaire in patients with brain metastases (BrM) treated with RT. <h3>Materials/Methods</h3> The BC-brain questionnaire was constructed with 3 subscales: Mobility, Thinking and CNS Symptoms. Patients with BrM from 5 BC Cancer centers completed this questionnaire at first visit and subsequent follow-up appointments. Summary scores of each subscale were calculated. Reliability, validity, known-group differentiation responsiveness were tested. <h3>Results</h3> 365 patients finished the first and 105 finished the follow-up questionnaire. Mobility, Thinking and subtotal score showed good reliability with Cronbach's α > 0.7. Multitrait scaling analysis showed good convergent and divergent validity. The subscales correlated well with the general QoL question and the subtotal score. The correlations between subscales range from 0.262 to 0.456 for baseline and from 0.378 to 0.597 for follow-up. Patients on dexamethasone had worse score on Mobility (p<0.001), Thinking (p=0.006), CNS symptoms (p=0.003), the general QoL (p=0.010) and subtotal score (p<0.001) than patients not on dexamethasone. Patients with a KPS of </= 70 had worse score on Mobility (p<0.001), Thinking (p=0.001), CNS symptoms (p<0.001), the general QoL (p<0.001) and subtotal score (p<0.001) than patients with a KPS of > 70. <h3>Conclusion</h3> The BC-brain questionnaire has good reliability and validity. It is short in length and is easy to administer without adding much patient burden in routine clinical care. It is a new Patient Report Outcome (PRO) instrument to measure the quality of life in BrM patients treated with RT, especially for use in routine clinical care. Future research could explore the feasibility of including HRQOL in patient selection and treatment decision making for brain metastases patients.