In their focal article, Watts et al. (Reference Watts, Gray and Medeiros2021) discuss the important yet often ignored side effects associated with many widely known organizational interventions including intelligence testing and urge industrial and organizational (I-O) psychologists to pay more attention to them. Although I agree that I-O psychologists should not merely focus on the benefits of intelligence testing (e.g., validity) but also its side effects (e.g., adverse impact), I would like to take this opportunity to put in perspective several of the side effects mentioned in the focal article, given their potential to be misleading and perpetuate misconceptions about intelligence testing.Footnote ¹

First, Watts et al. (Reference Watts, Gray and Medeiros2021) state that intelligence testing “has in some instances been associated with noteworthy side effects, such as … illegal discrimination against minority groups” (p. X) and that “on average, organizations that used these [traditional intelligence] tests to select applicants increased their odds of discriminating against minority group members” (p. X). In this excerpt, Watts et al. use two strong words—“illegal” and “discrimination”—without sufficient qualifiers. The use of these words has the potential to elicit the wrong impression, particularly among laypeople and nonexperts, that (a) the use of a traditional (written) GMA test as a selection procedure is (likely) ruled to be illegal in court and (b) such tests are less predictive of job performance among minority groups than among the majority group. Speaking from a legal standpoint, such demonstrations in court often rely on cumulative research findings rather than on local validation studies plagued with sampling error and other methodological artifacts (Schmidt, Reference Schmidt and Locke2009). Therefore, GMA tests are (and should be) quite defensible in court given the extensive meta-analytic evidence that such tests are highly predictive of job performance, and, relevantly, their validity does not differ across major ethnic groups (e.g., Roth et al., Reference Roth, Le, Oh, Van Iddekinge, Buster, Robbins and Campion2014; Schmidt, Reference Schmidt1988). Also, GMA tests are not predictively biased against minority groups, meaning that both minority and majority applicants with the same GMA test scores have practically the same level of later job performance (Berry & Zhao, Reference Berry and Zhao2015).Footnote ² As Schmidt (Reference Schmidt and Locke2009) noted, employers have been winning more and more such suits since the mid-1980s, and there are simply fewer such suits in recent years; “currently, less than 1% of employment-related lawsuits are challenges to selection tests or other hiring procedures” (p. 12). In summary, there is ample research evidence that GMA tests, if properly used following professional guidelines such as the Society for Industrial and Organizational Psychology’s (SIOP; 2018) Principles, are predictively fair or unbiased and, as such, a legally defensible selection procedure in most, if not all, cases (Schmidt, Reference Schmidt and Locke2009).

Second, what is referred to as the side effects of GMA tests in the focal article appears to be the well-known concept of disparate or adverse impact. However, adverse impact is not necessarily a real (vs. potential) legal risk or an illegal side effect. Cumulative research shows that members of some minority groups have lower average scores on GMA tests than members of the majority group (Roth et al., Reference Roth, Van Iddekinge, DeOrtentiis, Hackney, Zhang and Buster2017). If applicants are selected based solely on their GMA test scores in a top-down manner, this can lead to lower hiring rates on average for lower scoring minority groups. This was well known even in the early 1980s. Government agencies such as the Equal Employment Opportunity Commission started to refer to these lower hiring rates as “adverse impact,” which is rarely a real legal risk in the case of GMA tests as discussed above. (As Schmidt [Reference Schmidt and Locke2009] noted, “the term adverse impact is deceptive, because it implies that the GMA tests create the difference in test scores, when in fact the tests only measure real preexisting differences in mental skills” [p. 12].) Additionally, not using written GMA tests does not necessarily remove the possibility of adverse impact as long as cognitively loaded constructs (e.g., GMA and job-relevant knowledge, skills, and specific abilities) are measured using other selection procedures (e.g., job interviews; Oh, Reference Oh2013). Then, what is a good enough, though not perfect, and lawful solution to adverse impact or the so-called “validity–diversity dilemma”? The answer, fortunately, lies well within the realm of currently accepted best personnel selection practices. Specifically, GMA tests can be supplemented with valid noncognitive predictors that show little, if any, adverse impact (e.g., conscientiousness). This selection battery is not only predictive of later job performance but also helps increase diversity by reducing the adverse impact associated with GMA tests (Ployhart & Holtz, Reference Ployhart and Holtz2008, p. 168). In recent years, some employers have also attempted balancing the biobjectives of performance (validity) and diversity using Pareto-optimal weighting methods borrowed from the multiple-objective optimization literature in engineering and economics (De Corte et al., Reference De Corte, Lievens and Sackett2021; Rupp et al., Reference Rupp, Song and Strah2020).Footnote ³ In summary, the adverse impact associated with intelligence testing is not an intractable risk, as most employers (can) measure valid noncognitive traits (e.g., conscientiousness) in addition to GMA in hiring without incurring too much additional cost.

Third, as discussed in their focal article and above, “a number of approaches have been proposed with the goal of mitigating the side effects of traditional intelligence tests (e.g., score banding, alternative measurement methods) … some of these approaches have demonstrated partial success (Ployhart & Holtz, Reference Ployhart and Holtz2008), but none have been found to eliminate all concerns of bias” (p. X). However, this statement is only half true, because they do not mention perhaps the most potent solution to this issue, within-group norming, which can equalize minority and nonminority hiring rates and thus eliminate adverse impact. However, this solution is not without legal barriers. As discussed in Sackett and Wilk (Reference Sackett and Wilk1994, p. 929), although within-group norming was recommended as the solution to the adverse impact associated with the use of intelligence testing as a selection procedure by a National Academy of Sciences (NAS) committee (Hartigan & Wigdor, 1989), the 1991 Civil Rights Act made such score adjustments “an unlawful practice for an employer,” leaving hiring managers with more questions than answers.

Fourth, Watts et al. (Reference Watts, Gray and Medeiros2021) state that “although this approach [traditional assessments of g] to intelligence testing has been criticized on a number of fronts (e.g., Schneider & Newman, Reference Schneider and Newman2015), we focus on the use of g because such tests continue to be used frequently in employee selection systems” (p. X, bracket added). There are two problems with this statement. First, Watts et al. ignore the cumulative research findings that show the use of specific abilities instead of GMA is not generally recommended, particularly in predicting job and training performance (both broad). Specifically, the validity of GMA tests for job and training performance is generally higher than that of specific aptitudes—even when specific aptitudes are chosen to match the most important aspects of job performance (i.e., spatial perception for the pilot job). Second, another important aspect of GMA is that it is the broadest of all cognitive abilities. Narrower abilities, such as verbal, quantitative, and spatial abilities, and specific aptitude measures also predict job performance, but this is largely attributed to their partially measuring GMA. In other words, when a test of verbal ability predicts job or training performance, it is the GMA part of that test (g)—not much of the verbal part—that primarily does the predicting, thus “not much more than g” (Ree & Earles, Reference Ree and Earles1991; Ree et al., Reference Ree, Earles and Teachout1994). Moreover, it is hard to believe that Schneider and Newman’s (2015) article is cited as an example to illustrate that “intelligence testing has been criticized on a number of fronts.” My understanding of this review paper is that researchers and practitioners should make better use of specific aptitudes, as they can be as predictive as GMA in predicting “specific” (vs. broad) performance dimensions. For example, Schneider and Newman (Reference Schneider and Newman2015) stated the following as one of the most important implications from their review: “Past findings that show specific abilities do not offer strong unique prediction of general criteria (see Ree & Carretta, Reference Ree and Carretta2002) are not surprising (i.e., they are consistent with the compatibility principle), but such results constitute insufficient grounding from which to dismiss the validity of specific abilities. Specific abilities should predict specific job performance criteria, not overall job performance” (p. 25).

Fifth, Watts et al. (2011) state, “for some of these examples (e.g., traditional intelligence testing), I-O psychologists have played a critical role in shedding much light on side effects” (p. X). This is largely true, but not entirely. As discussed above, although the NAS recommended within-group norming as the most scientific solution to the validity–diversity dilemma, the 1991 Civil Rights Act determined it as an unlawful practice for nonscientific reasons (Sackett & Wilks, Reference Sackett and Wilk1994). However, there was no major protest to this decision from I-O psychologists. In a poignant (in my opinion) TIP article, Schmidt (Reference Schmidt2006) wrote,

Thus, a real side effect of intelligence testing not mentioned in Watts et al. is political risk.

Sixth, based on a survey of 5,000 Society for Human Resource Management members whose title was at the manager level and above, Rynes et al. (Reference Rynes, Colbert and Brown2002) found that 72% of the 959 respondents did not know or believe that GMA tests are more predictive of job and training performance than most noncognitive selection procedures such as conscientiousness measures (see Schmidt & Hunter, Reference Schmidt and Hunter1998). This problem is not limited to the United States but widely observed in other countries (e.g., Tenhiälä et al., Reference Tenhiälä, Giluk, Kepes, Simon, Oh and Kim2016). Evidently, another real serious side effect of intelligence testing seems to be ignorance or disbelief of the enormous research evidence regarding the validity and utility of GMA tests among human resources (HR) managers.

Last, it is also important to recognize the side effects associated with not using, rather than using, GMA tests as a major selection procedure. A well-controlled, natural quasi-experiment (e.g., U.S. Steel Plant at Fairless Hill, PA) introduced in Schmidt (Reference Schmidt and Locke2009) highlights the substantial economic loss associated with hampering the use of GMA tests as a selection procedure (e.g., increased training time and costs; decreased productivity). This point is not limited to intelligence testing but applicable to other organizational interventions.

In conclusion, although I agree with the general theme of the focal article, I think they fail to put in perspective the sheer complexity around the side effects of intelligence testing. In short: Perfect is the enemy of good enough! This seems to be the perfect phrase for a GMA test because its benefits, such as high validity and utility, outweigh its side effects, whether real or not. However, pseudo, fake, and voodoo science (to be clear, not intended for the focal article) seem to focus unevenly more on its (potential) side effects and argue that unless perfect, a GMA test should probably not be used as a selection procedure, thus doing more harm than good. All of us, as I-O psychologists, need be beware of this doctrine, as it only pushes us further away from rather than closer to the truth.