Table 3. Estimated mean difference in the serum LDL cholesterol (mg/dL) and dietary cholesterol (mg/1,000 kcal) higher by 1 SD^* by employment status and sequential regression models in the INTERLIPID study in Japan, 1996–1999.

Model	Men (n = 533)				Women (n = 506)
	LDL-C (mg/dL)	95% CI		P value	LDL-C (mg/dL)	95% CI		P value
Unadjusted	−3.16	−5.52	−0.79	0.009	−1.64	−4.30	+1.02	0.226
Model 1
Employed in a company	−4.13	−6.59	−1.68	0.001	−3.05	−6.12	+0.03	0.052
The others**	+8.56	0.00	+17.11	0.050	+1.71	−3.55	+6.98	0.523
Model 2
Employed in a company	−3.03	−5.51	−0.56	0.017	−1.00	−4.27	+2.28	0.551
The others**	+9.13	+0.94	+17.31	0.029	+0.98	−3.98	+5.94	0.699
Model 3
Employed in a company	−3.02	−5.49	−0.54	0.017	−1.07	−4.34	+2.19	0.518
The others**	+9.08	+0.90	+17.27	0.030	+1.09	−3.86	+6.04	0.665

^*1 SD difference for dietary cholesterol is 67.5 mg/1,000 kcal for men and 65.9 mg/1,000 kcal for women.

^**“The others” includes self-employed, homemakers, farmers, fishermen, and retired employees. Coefficients for dietary cholesterol were based on the use of indicator variables for the employment status. Tests were also performed to clarify whether the coefficients differed between the employed and the others.

Model 1 = dietary cholesterol + employment status (“employed in a company”/ “the others”) + dietary cholesterol × employment status

Model 2 = Model 1 + age, BMI, menopausal status for women (before/in the middle or after), number of cigarettes, alcohol intake, SFA, PUFA, MUFA, TFA, soluble fiber, and site

Model 3 = Model 2 + education years

P values for the interaction term between dietary cholesterol and employment status (dietary cholesterol × employment status) are as follows: P = 0.005 for men and P = 0.126 for women in Model 1, P = 0.005 for men and P = 0.494 for women in Model 2, and P = 0.005 for men and P = 0.451 for women in Model 3.