Diagnostic issues affecting the epidemiology of fetal alcohol spectrum disorders.

BACKGROUND Epidemiological measures of the prevalence of fetal alcohol spectrum disorders (FASD) vary greatly in the literature. Irrespective of the methodology, the criteria to define a 'case' are set by the researchers. Hence, estimates of the prevalence of FASD primarily depend on the diagnostic criteria currently available. The problem lies therein - the aforementioned criteria are ill-defined. MATERIALS & METHODS A critical analysis of the diagnostic criteria from the Institute of Medicine, Hoyme, 4-Digit Diagnostic Code and Canadian guidelines was performed, with particular attention focused on the inconsistencies in specificities of the fetal alcohol syndrome (FAS) facial phenotype. RESULTS To date, the Canadian guidelines represent the only guidelines that have pushed for a uniform diagnostic capacity through harmonizing the IoM and 4-Digit Diagnostic Code criteria. In the absence of a reliable biochemical marker of effect to confirm maternal drinking during pregnancy, the importance and dependence on diagnostic guidelines for FASD is understated. With the availability of four published guidelines for diagnoses across the spectrum of FASD, there is a need to reach a set standard globally. There are profound implications of relaxed and strict diagnostic approaches on FAS prevalence reporting in the literature. CONCLUSIONS This review exposes the clinical burden of diagnosing the range of FASD with disputing diagnostic criteria. Discrepancies in the criteria pose a danger to the validity of FASD diagnoses with respect to inaccurate estimates of incidence and prevalence. In turn, these discrepancies risk compromising the future healthcare of affected individuals with regards to intervention, counselling and treatment.