Meeting assumptions in the estimation of reliability

Researchers and psychometricians have long used Cronbach’s as a measure of reliability. However, there have been growing calls to replace Cronbach’s with measures that have more defensible assumptions. One of the most common and straightforward recommended reliability estimates is !. After a review of reliability and its estimation in Stata, I introduce the community-contributed command omegacoef. This command reports McDonald’s ! in a format similar to the base alpha command. omegacoef provides Stata users the ability to easily compute estimates of reliability with the confidence that the necessary statistical assumptions are met.