title: Practice effects and the use of alternate forms in serial neuropsychological testing.
abstract: Accurate understanding of practice characteristics, performance stability, and error on neuropsychological tests is essential to both valid clinical assessment and maximization of signal detection for clinical trials of cognitive enhancing drugs. We examined practice effects in 28 healthy adults. As part of a larger study using donepezil and simulating a Phase I trial, participants were randomized into: placebo, no-treatment and donepezil. Donepezil results are presented elsewhere. Neuropsychological tests were administered in a fixed order for 6 weeks, with alternate forms available for most tests. Despite alternate forms, ANOVAs revealed significant improvements for the pooled control group (placebo and no-treatment) on all tests except Letter Number Sequencing and Trails B. Learning occurred principally in the first three to four sessions. PASAT and Stroop interference showed the greatest learning. Thus, serial assessment with alternate forms may attenuate retest effects on some tests, but continued learning occurs on novel tests or those in which an advantageous test-taking strategy can be identified. Alternate forms and baseline practice sessions may help control early, rapid improvements in clinical trials.
authors.affiliation: Department of Psychiatry, University of Iowa College of Medicine, 1-321 MEB, 200 Hawkins Dr., Iowa City, Iowa 52242, USA. leigh-beglinger@uiowa.edu
authors.forename: Leigh J
authors.initials: LJ
authors.lastname: Beglinger
authors.forename: Brenda
authors.initials: B
authors.lastname: Gaydos
authors.forename: Oranee
authors.initials: O
authors.lastname: Tangphao-Daniels
authors.forename: Kevin
authors.initials: K
authors.lastname: Duff
authors.forename: David A
authors.initials: DA
authors.lastname: Kareken
authors.forename: Jane
authors.initials: J
authors.lastname: Crawford
authors.forename: Philip S
authors.initials: PS
authors.lastname: Fastenau
authors.forename: Eric R
authors.initials: ER
authors.lastname: Siemers
mesh_terms: D000328:Adult; D000077265:Donepezil; D004311:Double-Blind Method; D004522:Educational Status; D005260:Female; D006801:Humans; D007189:Indans / Q000494:pharmacology*; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D018697:Nootropic Agents / Q000494:pharmacology*; D010880:Piperidines / Q000494:pharmacology*; D011214:Practice, Psychological; D012016:Reference Values; D015203:Reproducibility of Results; D017603:Signal Detection, Psychological / Q000187:drug effects*; D013997:Time Factors
chemical_list: D007189:Indans; D018697:Nootropic Agents; D010880:Piperidines; D000077265:Donepezil