Thus, by continuing to use alpha as the estimate of reliability test constructors and test users do themselves injustice until they recognize the availability of better alternatives. Better alternatives to alpha exist but are hardly known, let alone used to assess reliability. Alpha is a lower bound to the reliability, in many cases, even a gross underestimate, and alpha cannot have a value that could be the reliability based on the usual assumptions about measurement error. Two problems concerning alpha continue to be pervasive in test construction and test use. Probably no other statistic has been reported more often as a quality indicator of test scores than Cronbach’s (1951) alpha coefficient, and presumably no other statistic has been subject to so much misunderstanding and confusion.
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