Comparing diagnostic classification of neurobehavioral disorder associated with prenatal alcohol exposure with the Canadian fetal alcohol spectrum disorder guidelines: a cohort study.

backgroundDiagnostic criteria have recently been introduced in the Diagnostic and Statistical Manual of Mental Disorders, 5th edition (DSM-5), for neurobehavioral disorder associated with prenatal alcohol exposure (ND-PAE). The purpose of this study is to assess the classification of this condition using the Canadian fetal alcohol spectrum disorder (FASD) multidisciplinary diagnostic guidelines as the standard of comparison. First, classification of ND-PAE was compared with Canadian FASD diagnoses of fetal alcohol syndrome (FAS), partial FAS and alcohol-related neurodevelopmental disorder. Second, classification of ND-PAE was compared with FAS and pFAS only, a criterion for which includes facial features highly predictive of prenatal alcohol exposure and effects.

methodsEighty-two patients underwent multidisciplinary clinical evaluations using the Canadian FASD diagnostic guidelines between 2011 and 2015. Two clinicians independently reviewed patient files for evidence of diagnostic criteria for ND-PAE when applying an impairment cut-off level of 2 or more standard deviations below the mean, or clinically significant impairment in the absence of standardized norm-referenced measures.

resultsGood interrater reliability was established between clinicians (κ = 0.79). Classifications of ND-PAE and Canadian FASD diagnoses, including alcohol-related neurodevelopmental disorder, were moderately correlated (Cramer

interpretationAlthough there is considerable overlap between both sets of criteria, ND-PAE was less likely to identify patients with FASD. Although the neurobehavioral domains assessed by ND-PAE are supported in research, its diagnostic structure restricts the identification of FASD at the impairment threshold of 2 or more standard deviations. A disconnect remains with regard to impairment thresholds between FASD, which relies on neurodevelopmental data, and ND-PAE, which relies on clinical judgment.