title: Empirical Derivation and Validation of a Clinical Case Definition for Neuropsychological Impairment in Children and Adolescents.
abstract: Neuropsychological assessment aims to identify individual performance profiles in multiple domains of cognitive functioning; however, substantial variation exists in how deficits are defined and what cutoffs are used, and there is no universally accepted definition of neuropsychological impairment. The aim of this study was to derive and validate a clinical case definition rule to identify neuropsychological impairment in children and adolescents. An existing normative pediatric sample was used to calculate base rates of abnormal functioning on eight measures covering six domains of neuropsychological functioning. The dataset was analyzed by varying the range of cutoff levels [1, 1.5, and 2 standard deviations (SDs) below the mean] and number of indicators of impairment. The derived rule was evaluated by bootstrap, internal and external clinical validation (orthopedic and traumatic brain injury). Our neuropsychological impairment (NPI) rule was defined as "two or more test scores that fall 1.5 SDs below the mean." The rule identifies 5.1% of the total sample as impaired in the assessment battery and consistently targets between 3 and 7% of the population as impaired even when age, domains, and number of tests are varied. The NPI rate increases in groups known to exhibit cognitive deficits. The NPI rule provides a psychometrically derived method for interpreting performance across multiple tests and may be used in children 6-18 years. The rule may be useful to clinicians and scientists who wish to establish whether specific individuals or clinical populations present within expected norms versus impaired function across a battery of neuropsychological tests.
authors: 1Department of Psychology,University of Montreal,Montreal,Quebec,Canada.
authors: Miriam H
authors: MH
authors: Beauchamp
authors: 3Neurosciences program (Brain Injury and Rehabilitation),Alberta Children's Hospital,Calgary,Alberta,Canada.
authors: Brian L
authors: BL
authors: Brooks
authors: 6Department of Psychology,University of Calgary,Calgary,Alberta,Canada.
authors: Nick
authors: N
authors: Barrowman
authors: 7Clinical Research Unit,Children's Hospital of Eastern Ontario Research Institute,Ottawa,Ontario,Canada.
authors: Mary
authors: M
authors: Aglipay
authors: 8Bloorview Research Institute,Holland Bloorview Kids Rehabilitation Hospital,Toronto,Ontario,Canada.
authors: Michelle
authors: M
authors: Keightley
authors: 11Behavioural Neurosciences & Consultation-Liaison program,Children's Hospital of Eastern Ontario,Ottawa,ON.
authors: Peter
authors: P
authors: Anderson
authors: 5Alberta Children's Hospital Research Institute,University of Calgary,Calgary,Alberta,Canada.
authors: Keith O
authors: KO
authors: Yeates
authors: 12Children's Hospital of Eastern Ontario Research Institute,Ottawa,Ontario,Canada.
authors: Martin H
authors: MH
authors: Osmond
authors: 12Children's Hospital of Eastern Ontario Research Institute,Ottawa,Ontario,Canada.
authors: Roger
authors: R
authors: Zemek
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003072:Cognition Disorders / Q000175:diagnosis* / Q000523:psychology*; D004522:Educational Status; D005260:Female; D006801:Humans; D007182:Income; D008297:Male; D009483:Neuropsychological Tests; D017063:Outcome Assessment, Health Care; D011594:Psychometrics
keywords: Assessment; Brain injury; Cognition; Neuropsychology; Pediatric; Performance