title: Practice effect and normative data of an HIV-specific neuropsychological testing battery among healthy Thais.
abstract: OBJECTIVE
  A longitudinal cohort study was conducted in Bangkok, Thailand between 2008 and 2013 in order to determine the practice effect of serial neuropsychological testing and establish normative data among normal (HIV-uninfected) Thai volunteers.
  
  
  METHODS
  The authors enrolled 511 cognitively healthy individuals (HIV-uninfected, no drug abuse or other previous/current neurological or psychological conditions) to assess baseline performance on a HIV-specific neuropsychological testing battery. Ninety-nine subjects were re-assessed at 6 and 12 months to evaluate practice effects.
  
  
  RESULTS
  The mean age of the 99 subjects completing longitudinal visits was 49.2 years and 53 were male. The authors identified improved mean raw scores on most neuropsychological tests with repeated measurements; however only change in WHO Auditory Verbal Learning Test (AVLT) scores (learning, attention, immediate and delayed recall tasks) met statistical significance, with larger differences seen between baseline and 6-month compared to 6 and 12 months follow-up. Older age correlated with poorer baseline raw score, and was a predictor of worse performance at 6 months and 12 months on several tasks. Level of education was associated with practice effects on several tests. No similar effects were observed with gender.
  
  
  CONCLUSIONS
  The authors identified improved performance after repeated measurements revealing a significant practice effect on an HIV-specific neuropsychological testing battery employed in Bangkok, Thailand. Main predictors were age and educational attainment.
authors.forename: Pasiri
authors.initials: P
authors.lastname: Sithinamsuwan
authors.forename: Nicholas
authors.initials: N
authors.lastname: Hutchings
authors.forename: Jintanat
authors.initials: J
authors.lastname: Ananworanich
authors.forename: Lauren
authors.initials: L
authors.lastname: Wendelken
authors.forename: Putthachard
authors.initials: P
authors.lastname: Saengtawan
authors.forename: Robert
authors.initials: R
authors.lastname: Paul
authors.forename: Nitiya
authors.initials: N
authors.lastname: Chomchey
authors.forename: James L K
authors.initials: JL
authors.lastname: Fletcher
authors.forename: Thep
authors.initials: T
authors.lastname: Chalermchai
authors.forename: Victor
authors.initials: V
authors.lastname: Valcour
mesh_terms: D000328:Adult; D000368:Aged; D044466:Asian People; D015331:Cohort Studies; D005260:Female; D015658:HIV Infections / Q000523:psychology*; D006801:Humans; D008137:Longitudinal Studies; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011597:Psychomotor Performance; D012016:Reference Values; D013785:Thailand