title: Estimation of K-WAIS-IV Premorbid Intelligence in South Korea: Development of the KPIE-IV.
abstract: OBJECTIVE
  The accurate estimation of premorbid intellectual functioning in patients with known or suspected cognitive impairment is crucial for clinicians. However, there is no reliable method for estimating premorbid intelligence in South Korea. The purpose of this study was to develop the Korea Premorbid Intelligence Estimate (KPIE) as an estimate of the premorbid intellectual functioning.
  
  
  METHODS
  Data from the Korean WAIS-IV standardization sample were used to generate several Full Scale Intelligence Quotient (FSIQ) estimation formulas using demographic variables and current WAIS-IV subtest performance. The standardization sample (N = 1216) was randomly divided into two groups: the first group was used to develop the formulas and the second group was used to validate the prediction equations. Age, education, gender, region of the country, and select subtest raw scores (Vocabulary, Information, Matrix Reasoning, and Visual Puzzle) were used as predictor variables.
  
  
  RESULTS
  Five KPIE-4 equations were generated. Estimated FSIQ derived from the KPIE-4 equation is highly correlated with K-WAIS-IV FSIQ.
  
  
  CONCLUSIONS
  The resulting formulas for estimating premorbid FSIQ were highly significant and precise in predicting FSIQ scores of participants in the K-WAIS-IV normative sample. These equations provide a means for clinicians to estimate intellectual functioning in adults, and can be utilized as a method of estimating individuals premorbid functioning.
authors.affiliation: a Department of Psychiatry, Samsung Medical Center , Sungkyunkwan University School of Medicine , Seoul , South Korea.
authors.forename: Sung-Geon
authors.initials: SG
authors.lastname: Kim
authors.affiliation: b Department of Psychiatry, Depression Center, Samsung Medical Center , Sungkyunkwan University School of Medicine , Seoul , South Korea.
authors.forename: Eun-Ho
authors.initials: EH
authors.lastname: Lee
authors.affiliation: c Department of Psychology , Chungbuk National University , Chungju , South Korea.
authors.forename: Soon-Taeg
authors.initials: ST
authors.lastname: Hwang
authors.affiliation: c Department of Psychology , Chungbuk National University , Chungju , South Korea.
authors.forename: Kwangbai
authors.initials: K
authors.lastname: Park
authors.affiliation: d Department of Psychology , Seoul National University , Seoul , South Korea.
authors.forename: Jeanyung
authors.initials: J
authors.lastname: Chey
authors.affiliation: e Department of Education , Chinju National University of Education , Chinju, South Korea.
authors.forename: Sang-Hwang
authors.initials: SH
authors.lastname: Hong
authors.affiliation: a Department of Psychiatry, Samsung Medical Center , Sungkyunkwan University School of Medicine , Seoul , South Korea.
authors.forename: Ji-Hae
authors.initials: JH
authors.lastname: Kim
mesh_terms: D000328:Adult; D003072:Cognition Disorders / Q000175:diagnosis* / Q000523:psychology; D005260:Female; D006801:Humans; D007360:Intelligence; D007361:Intelligence Tests; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests / Q000592:standards*; D011237:Predictive Value of Tests; D012015:Reference Standards; D056910:Republic of Korea; D014825:Vocabulary; D014888:Wechsler Scales / Q000592:standards*
keywords: Estimated intelligence; KPIE.; OPIE; Premorbid intelligence; WAIS-IV