Table 1.

Statistical power of each method of analysis

Correlation	ρ = 0.2	ρ = 0.35	ρ = 0.5	ρ = 0.65	ρ = 0.8
POST	70.5%	70.5%	70.5%	70.5%	70.5%
FRACTION	45.1%	56.4%	67.0%	82.7%	97.1%
CHANGE	50.7%	59.2%	70.5%	84.8%	97.7%
ANCOVA	72.3%	76.1%	82.3%	90.8%	98.6%