n	Singh et al.’s study [6]					Present study			h_P − h_Y
n	LL_P	UL_P	LL_P/3	UL_P/3	h_P	LL_Y	UL_Y	h_Y	h_P − h_Y
25	−0.746	0.75	−0.249	0.250	0.499	−0.242	0.245	0.487	0.011
50	−0.522	0.506	−0.174	0.169	0.343	−0.167	0.173	0.340	0.003
75	−0.433	0.427	−0.144	0.142	0.287	−0.141	0.141	0.282	0.005
100	−0.373	0.365	−0.124	0.122	0.246	−0.121	0.122	0.243	0.003