Skip Navigation
Department of Health and Human Services
Slide Tray
0 slides

Return to Slide Library


Add Presentation to Slide Tray Presentation:

Comparative Effectiveness and Safety of Radiotherapy Treatments for Head and Neck Cancer

Slide: 21 of 36

Overview of Available Literature

The available literature featured a small body of randomized, controlled trials, accompanied by a larger body of poor-quality observational, nonrandomized studies. Study quality was assessed according to principles described in a reference guide for conducting comparative effectiveness reviews produced by AHRQ. In this context, poor-quality study refers to studies that have high potential for bias of results (e.g., single institution case series). The observational studies included in the review were clinically diverse with respect to patient characteristics and treatment setting, thereby creating uncertainty about whether results should be attributed to confounding rather than treatment differences. Details were often lacking among observational studies about patient characteristics and treatments, and it was not clear for any study whether well-done multivariable analyses were performed to adjust for differences.