The Flynn Effect and Its Clinical Implications

Flaws in Flynn Effect Research With the Wechsler Scales

“…The small reversal of the direction of the FE for PSI (−.11) previously reported by Gregoire et al (2016) was not observed in the current study. Gregoire et al (2016) suggested that the unexpected reversal may have been due to subtle changes introduced to the task demands of Symbol Search and Coding in the WISC-V.…”

“…Gregoire et al (2016) suggested that the unexpected reversal may have been due to subtle changes introduced to the task demands of Symbol Search and Coding in the WISC-V. Eliminating possible construct confounds in the task demands between WISC-IV and WISC-V, the current study found the rate of gain for PSI as 0.27 points per year in direction predicted by FE theory.…”

“…The WISC-IV/WISC-V counterbalanced study reported in the WISC-V Technical Manual (Wechsler, 2014) provides an accurate estimate of expected score changes for practitioners who switch from using WISC-IV to WISC-V with patients. Gregoire, Daniel, Llorente, and Weiss (2016) further analyzed those data in terms of the rates of gain in IQ scores across the time interval between standardization of the two test editions and reported an annualized rate of gain for FSIQ at 0.14, well below the theoretically expected rate of gain of 0.33 points per year. However, they noted that the composition of the FSIQ for WISC-IV and WISC-V differs substantially—as described above.…”

“…At first glance, the reversal in the trend for the processing speed subtests is surprising because the two subtests were apparently unchanged in the WISC-IV and the WISC-V. However, Gregoire et al (2016) noted that several subtle modifications were introduced in the WISC-V versions of Coding and Symbol Search (e.g., increased complexity of symbols to be drawn, number of search symbols, number of shapes per row and of rows per page). They opined that these modifications may have made the WISC-V version of both subtests more difficult, weakening their mean raw scores, and perhaps increasing extraneous sources of variance such as fine motor skill involved in writing, visual acuity, and visual tracking between rows.…”

“…Alternatively, given the female advantage in visual processing speed (Kaufman, Raiford, & Coalson, 2016), the higher proportion of girls in the counterbalanced study may have created differential practice effects for the group that took the more difficult version second. Gregoire et al (2016) discussed these and other confounds that can occur when generational shifts in intelligence are estimated across substantially different versions of a test.…”