Probability values: no lead zero

If the Principal Investigators of some X compound observed absolutely predestined data, then they'd have an integer for a P value, where P = 1. Absolute impossibility would be expressed as zero, as in zero probability, or P = 0.

But that's not what happens in drug studies. Instead, scientists proceed on the assumption that events occur in a probabilistic rather than predestined universe. Thus, a P value could never be expressed as a whole number, so AMA prefers that no lead zero appear with the decimal point. You'd write P ≥ .01, for example, rather than P ≥ 0.01.

The lead zero looks legitimate enough, even a little brave, all by itself to the left of the decimal point. But it's pointless, says AMA, because no value could possibly appear to the left of the decimal point without making the probability value useless. Hence, no lead zero.