Psychological measurement and the replication crisis: Four sacred cows.

Although there are surely multiple contributors to the replication crisis in psychology, one largely unappreciated source is a neglect of basic principles of measurement. We consider 4 sacred cows— widely shared and rarely questioned assumptions—in psychological measurement that may fuel the replicability crisis by contributing to questionable measurement practices. These 4 sacred cows are: (a) we can safely rely on the name of a measure to infer its content; (b) reliability is not a major concern for laboratory measures; (c) using measures that are difficult to collect obviates the need for large sample sizes; and (d) convergent validity data afford sufficient evidence for construct validity. For items a and d, we provide provisional data from recent psychological journals that support our assertion that such beliefs are prevalent among authors. To enhance the replicability of psychological science, researchers will need to become vigilant against erroneous assumptions regarding both the psychometric properties of their measures and the implications of these psychometric properties for their studies.