Title: 2.7 Does the SCAT5 10-word list improve the distribution of scores over the SCAT3 5-word list in professional hockey players?
Abstract: <h3>Objective</h3> The SCAT5 introduced Immediate Memory (IM) and Delayed Recall (DR)10-word lists to improve the ceiling effects found on SCAT3 5-word lists. We examined whether the 10-word lists improved the normative distribution of scores over the 5-word lists at baseline among professional hockey players. <h3>Design</h3> Retrospective Cohort. <h3>Setting</h3> Outpatient professional hockey. <h3>Participants</h3> English-language preference professional hockey players completed the SCAT3 5-word lists (n=1123) during pre-season in 2017 and SCAT5 10-word lists (n=1479) in 2019 for a total sample of 2602. <h3>Independent Variables</h3> 5-word vs. 10-word SCAT lists. <h3>Outcome Measures</h3> SCAT3 5-word IM and DR, SCAT5 10-word IM and DR scores. <h3>Main Results</h3> SCAT3 5-word IM lists produced a significant total score ceiling effect (<i>M</i>=14.62, md=15). A perfect score of 15 was achieved by 809 players (72%) on the 5-word list. In contrast, the SCAT5 10-word IM lists total scores were normally distributed (<i>M</i>=21.30, md=21). Only 1 player (0.1%) obtained a perfect score. Older players outperformed younger players (<i>r<sub>s</sub></i>=.19, <i>p</i><.001). Differences were found across language groups, <i>F</i>(7,1863)=7.14, <i>p</i><.001, and form versions of the lists, <i>F</i>(2,1868)=62.41, <i>p</i><.001. The 5-word DR component yielded similar distributions (<i>M</i>= 3.89, md=4) with 39% of players obtaining perfect scores. The 10-word mean DR score=7.02 (md=7). Again, older players outperformed younger players (<i>r<sub>s</sub></i>=.12, <i>p</i>< .001). No language differences emerged. <h3>Conclusions</h3> The 10-word lists improved the distribution of scores on the SCAT5 IM/DR tasks, which should improve the detection of impaired performance following concussion. Significant differences were found in age, language preference and form.