1. Estimate the sample size you will require.

Calculate the effect size of the different groups.

Table XI.1

Means and Variances in Laboratory Research study with two groups.

WBC, RBC AND HGB GROUP AND CONTROL

Independent Samples T-Test

Independent Samples T-Test
	t	df	p
WBC		-0.945		137		0.346
RBC		-2.068		137		0.041
HGB		-2.604		137		0.010
Note. Student's t-test.

Descriptive

Group Descriptive
	Group	N	Mean	SD	SE
WBC		0		70		7.531		3.404		0.407
		1		69		8.162		4.412		0.531
RBC		0		70		4.723		0.713		0.085
		1		69		4.968		0.684		0.082
HGB		0		70		13.167		1.877		0.224
		1		69		13.952		1.669		0.201