Use of Benford's law in drug discovery data.

Benford's law states that the distribution of the first digit of many data sets is not uniform. The first digit of any random number will be 1 almost 30% of the time, and larger digits occur as the first digit with lower and lower frequency, to the point where 9 occurs as a first digit only 5% of the time. Here, we demonstrate that several data sets in the field of drug discovery follow Benford's distribution, whereas 'doctored' data do not. Our findings indicate the applicability of Benford's law in assessing data quality in the field of drug discovery. We also propose a useful index of evaluating data quality based on Benford's law.