Detecting random responders with infrequency scales using an error-balancing threshold

Infrequency scales are becoming a popular mode of data screening, due to their availability and ease of implementation. Recent research has indicated that the interpretation and functioning of infrequency items may not be as straightforward as had previously been thought (Curran & Hauser, 2015), yet there are no empirically based guidelines for implementing cutoffs using these items. In the present study, we compared two methods of detecting random responding with infrequency items: a zero-tolerance threshold versus a threshold that balances classification error rates. The results showed that a traditional zero-tolerance approach, on average, screens data that are less indicative of careless responding than those screened by the error-balancing approach. Thus, the de facto standard of applying a "zero-tolerance" approach when screening participants with infrequency scales may be too stringent, so that meaningful responses may also be removed from analyses. Recommendations and future directions are discussed.