Comparison of Health State Utility Measures in Patients With Head and Neck Cancer.

Importance Accurate measurement of health state utilities (HU) is the cornerstone for cost-utility analyses and the valuation of quality of life for given health states. Current indirect methods of HU derivation lack face validity for patients with head and neck cancer. The appropriateness of these measures compared with direct methods, such as the standard gamble (SG), time trade-off (TTO), and visual analog scale (VAS), have not been assessed in this patient population. Objective To assess the convergent and construct validities of 5 different HU derivation methods in patients with head and neck cancer. Design, Setting, and Participants In a cross-sectional study, we recruited 100 consecutive patients with squamous cell carcinoma of the upper aerodigestive tract treated in the outpatient surgical oncology clinics of the Princess Margaret Cancer Centre from August 1 through October 31, 2014. We enrolled patients with a minimum of 3 months of follow-up after completion of treatment and no evidence of recurrent or metastatic disease. Participants completed SG, TTO, and VAS exercises, the EuroQoL instrument (EQ-5D), and the Health Utilities Index Mark 3 (HUI3) questionnaire. Data analysis was performed November 1 through December 15, 2014. Exposures Head and neck cancer and HU measures. Main Outcomes and Measures We assessed convergent validity of the 5 HU instruments through Spearman rank order correlation assessment. We determined construct validity through a priori hypotheses relating HU scores with clinical indexes of disease severity. Results The SG and TTO measures generated higher mean (SD) utility scores (0.91 [0.17] and 0.94 [0.14], respectively) than the VAS, EQ-5D, and HUI3 (0.76 [0.19], 0.82 [0.18], and 0.75 [025], respectively) ( P P P P P P  = .006], 0.62 [0.17] vs 0.83 [0.19] [ P  = .004], and 0.37 [0.29] vs 0.78 [0.22] [ P  = .004], respectively). Mean EQ-5D utility scores monotonically increased over time since completion of treatment (0.26 [ P  = .01]). The HUI3 yielded lower utility values for participants with laryngeal cancer (mean [SD], 0.59 [0.29]). The SG and TTO measures frequently generated utility scores that contradicted our hypothesized expectations. Conclusions and Relevance Indirect HU measures may be more reflective of the health status of patients with head and neck cancer than direct measures. Current instruments lack face validity for attributes germane to this population.