Table 4. Friedman Test Results for Paired Comparisons of the Shapiro-Wilk Goodness-of-fit Test P  Values for the Lognormal and Normal Models for Surgical and Total Procedure Times

n = 1,580 different CPT-anesthesia combinations with 1 degree of freedom. TT fitted both the lognormal and normal models better than ST; the lognormal model fits both ST and TT better than the corresponding normal model.

CPT = current procedural terminology; Ln = lognormal; TT = total procedure time; ST = surgical procedure time; N = normal.