Low birth-weight newborns are at higher risk for mortality. The official cut-off for "very low birthweight" is 1,500 grams. If the kid is 1,501 grams, doctors are advised to do less for him than if he were 1,499 grams.
Which results in a paradox:
'Researchers have shown that infants born just above 1,500 grams are more likely to die in the first year of life than those born just below, despite the fact that, in theory, a higher weight should increase an infant’s odds of survival.... In essence, because doctors are not using enough discretion — not acknowledging that infants just above 1,500 grams may be nearly as vulnerable as those below — lives are lost.'
Of course, on top of everything else, 1,500 seems like a suspiciously round number.
When a number seems too round,
I question whether the rule is sound.