TABLE 2.

B values obtained if a confounding factor, X, has various correlations by ranking with M and r, CoRR(X,M) and CoRR(X,r). The three sets of results are for three different R-random. The first B-value is from stratification into quintiles, and value in parenthesis is the coefficient of r in a multivariate regression of M on r and R(X).

CoRR (X.r)	CoRR (X,M)	B	CoRR (X,r)	CoRR (X,M)	B	CoRR (X,r)	CoRR (X,M)	B
0.09	0.09	−7.2(−7.2)	0.07	0.12	−7.2(−7.2)	0.08	0.08	−7.2(−7.2)
0.18	0.18	−7.0(−6.9)	0.16	0.21	−6.9(−6.8)	0.16	0.17	−7.0(−6.9)
0.34	0.34	−5.2(−5.5)	0.32	0.37	−5.3(−5.4)	0.33	0.33	−5.1(−5.6)
0.53	0.53	−2.1(−2.2)	0.51	0.55	−2.3(−2.0)	0.52	0.52	−2.1(−2.3)
0.69	0.69	+3.2(4.0)	0.68	0.70	+2.9(+4.0)	0.69	0.69	+3.3(+3.9)
0.79	0.79	10.5(11.3)	0.78	0.79	10.4(11.1)	0.79	0.79	10.8(11.2)
0 81	0.81	13.7(14.4)	0.81	0.82	13.7(14.2)	0.81	0.81	13.8(14.3)