We are excited to share another peer-reviewed publication! The reliability study conducted on the paper Gibson Test—now named Gibson Assessment of Cognitive Skills (GACS) has been published! The study, entitled Reliability Evidence for the Gibson Assessment of Cognitive Skills (GACS): A Brief Tool for Screening Cognitive Skills Across the Lifespan, was published in Psychology Research and Behavior Management, a peer-reviewed journal indexed in PubMed—the gold standard in medical research publishing. 

We examined and reported three sources of reliability evidence for the Gibson Assessment of Cognitive Skills, a paper-based, brief cognitive screening tool for children and adults measuring working memory, processing speed, visual processing, logic, and reasoning, and three auditory processing constructs: sound blending, sound segmenting, sound deletion along with work attack skills.

Overall coefficient alphas range from 0.80 to 0.94, producing a strong source of internal consistency reliability evidence. The split-half reliability coefficients ranged from 0.83 to 0.96 overall, producing a strong second source of reliability evidence. Across all ages, the test–retest reliability coefficients ranged from 0.83 to 0.98. The evidence collected for the current study suggests that the GACS is a reliable brief screening tool for assessing cognitive skill performance in both children and adults. (Note that the validity evidence was previously examined and published in the Technical Manual and in a study led by Elizabeth Moxley-Paquette. This was a reliability study.)

Takeaways from the Study:

• The Gibson Assessment of Cognitive Skills is a reliable tool for screening cognitive skills across the lifespan.
• The reliability of the GACS has been thoroughly examined and subjected to scientific peer review.
• The reliability evidence matches or exceeds the reliability evidence for other cognitive tests including the WISC-V, NEPSY-II, DAS-II, CANTAB, and CNS Vital Signs.
• The GACS is the only published single cognitive screening assessment that measures three narrow abilities of auditory processing (blending, segmenting, deletion) as well as Word Attack skills.

The full article can be accessed at the link below:

Moore, A.L., Miller, T.M., & Ledbetter, C. (2021). Reliability Evidence for the Gibson Assessment of Cognitive Skills (GACS): A Brief Tool for Screening Cognitive Skills Across the Lifespan. Psychology Research and Behavior Management, 14, 31-40. https://doi.org/10.2147/PRBM.S291574.