A review and meta-analysis of colorectal cancer utilities

Objective. To perform a systematic review of utility weights for colorectal cancer (CRC) health states reported in the scientific literature and to determine the effects of disease factors, patient characteristics, and utility methods on utility values. Methods. We identified 26 articles written in English and published from January 1980 to January 2013, providing 351 unique utilities for CRC health states elicited from 6546 unique respondents. The CRC utility data were analyzed using linear mixed-effects models with CRC type, stage, time to or from initial care, utility measurement instrument, and administration method as independent variables. Results. In the base case model, the estimated utility for a patient with stage I to III CRC more than 1 year after surgery, rated using a self-administered time tradeoff instrument, was 0.90. Stage, time to or from initial care, and utility measurement instrument were associated with statistically significant utility differences ranging from -0.19 to 0.02. Utilities for patients with stage IV cancer were 0.19 lower (P<0.001) than for those with stage I to III cancer. Utilities elicited at more than 1 year after surgery were 0.05 higher than those elicited at 3 months after surgery (P = 0.008). Estimates of differences between utility measurement instruments were sensitive to how repeated scores in the same patient group were treated, and other findings were sensitive to how the disease stage was modeled and method of administration. Conclusions. Variations in reported utilities are associated with factors such as cancer stage, time to or from initial care, and utility measurement instrument. More research is needed to study why apparently similar patients report different quality of life.