How mathematics warp biology: round-off of umbilical cord blood gas case value decimals distorts calculation of metabolic acidosis at birth.
Objective. To illustrate the impact on settling neonatal metabolic acidosis diagnosis by rounding off pH and base deficit (BD) case value decimals. Design. Comparative study. Setting. University maternity units. Sample. Umbilical cord arterial blood gas values from 18 831 newborns. Main outcome measures. Prevalences of pH