Pearson's Coefficient of skewness is defined as:
The coefficient used for checking the skewness of data, is called as the Karl Pearson coefficient, and is calculated as (Mean - Mode) S.D. Ref: Instant Medical Biostatistics, By Ranjan Das, Papri N. Das, 2009 Ane's Instant Medical Series, Page 41, 42.
(Mean-Mode) / SD
(Median-Mode) / SD
SD / (Mean - Mode)
SD / (Median -Mode)