It is imperative to collect validity evidence prior to interpreting and using test scores. During the process of collecting validity evidence, test developers should consider whether test scores are contaminated by sources of extraneous information. This is referred to as construct irrelevant variance, or the “degree to which test scores are affected by processes that are extraneous to the test’s intended purpose” (AERA et al., 2014, p. 12). One possible source of construct irrelevant variance is violating item-writing guidelines, such as to “avoid the use of none-of-the-above” in multiple-choice items (Rodriguez, 2016, p. 268).
Numerous studies have been conducted with regards to how none-of-the-above (NOTA) impacts item statistics, such as item difficulty, item discrimination, and test score reliability. The impacts of NOTA on item statistics are mixed and often depend on whether NOTA is the correct or incorrect option. In the case of NOTA as the incorrect option, NOTA tends to be more frequently selected by examinees (Garcia-Perez, 1993; Frary, 1991). This increased selection is hypothesized to be due to a potential selection tendency that examinees possess toward NOTA (Butler, 2018). While this tendency toward selecting NOTA is hypothesized in the literature, there has not yet been a study which tests this hypothesis.
In the current study, I extended previous NOTA literature to explore whether item difficulty varies across groups of examinees who receive a test with NOTA and a test without NOTA, after controlling for examinee ability. I also tested whether there is a hypothesized selection tendency toward NOTA. Overall, as described in previous research, NOTA resulted in mixed results. I discuss these results, as well as future areas of NOTA research