title: The frequency-amplitude gradient in the sleep EEG of children and its diagnostic significance.
abstract: OBJECTIVE
  1014 EEGs of children in the 3-months to 12-years age group were obtained during sleep with the purpose of assessing the frequency and amplitude gradient (FAG) its absence thought to be an indicator of neurological disorder.
  
  
  METHODS
  FAG findings were divided into present/absent. The neurological findings were classified according to the presence (abnormal neurological finding-ANF) or absence (normal neurological finding-NNF) of neurological disorder. The association and significance between FAG and neurological findings was determined by prevalence ration (PR) and chi-square test (chi2).
  
  
  RESULTS
  FAG showed a characteristic distributions of voltage output during non-REM sleep, stage II, in the 3-months to 5-years age group with NNF. The PR and the chi2 test demonstrated a strong association between FAG absent and ANF.
  
  
  CONCLUSIONS
  FAG is an age-dependent EEG sleep parameter and absence of FAG in the 3-months to 5-years age group is highly suggestive of neurological disorder.
authors.affiliation: Postgraduate Program in Health Sciences, Universidade Federal do Rio Grande do Norte, Natal, RN, Hospital Universitário de Brasília, Brazil.
authors.forename: Carlos Nogueira
authors.initials: CN
authors.lastname: Aucélio
authors.forename: Ernst
authors.initials: E
authors.lastname: Niedermeyer
authors.forename: Aurea Nogueira de
authors.initials: AN
authors.lastname: Melo
mesh_terms: D017677:Age Distribution; D000367:Age Factors; D001921:Brain / Q000254:growth & development; D016009:Chi-Square Distribution; D002648:Child; D002675:Child, Preschool; D016001:Confidence Intervals; D004569:Electroencephalography; D006801:Humans; D007223:Infant; D009422:Nervous System Diseases / Q000175:diagnosis*; D012890:Sleep / Q000502:physiology*