title: Comparability, reliability, and practice effects on alternate forms of the Digit Symbol Substitution and Symbol Digit Modalities tests.
abstract: The present study examined the comparability of 4 alternate forms of the Digit Symbol Substitution test and the Symbol Digit Modalities (written) test, including the original versions. Male contact-sport athletes (N = 112) were assessed on 1 of the 4 forms of each test. Reasonable alternate form comparability was demonstrated through establishing normality of form distributions and conducting pairwise form comparisons of means, variability, and intraclass correlations. Nonetheless, alternate forms are likely an insufficient means of controlling practice in speeded measures at brief (1-2 weeks) retest intervals. Reliable change indices demonstrated that practice must be accounted for in individual retesting.
authors: Cognitive Psychophysiology Laboratory, School of Medicine, University of Queensland, Herston, QLD, Australia. s309339@student.uq.edu.au
authors: Anton
authors: A
authors: Hinton-Bayre
authors: Gina
authors: G
authors: Geffen
mesh_terms: D000293:Adolescent; D000328:Adult; D001930:Brain Injuries / Q000150:complications; D003072:Cognition Disorders / Q000175:diagnosis / Q000209:etiology; D003710:Demography; D006801:Humans; D011214:Practice, Psychological; D015203:Reproducibility of Results; D013177:Sports; D013561:Symbolism