Table 3.

Results of Intention-to-treat and Per-protocol Analysis Estimating the Association between CaD Supplementation and Heart Failure Incidence - The Vitamin D and calcium (CaD) Trial of the Women’s Health Initiative (WHI) Study, 1995 – 2005

Study population	Intention-to-treat analysis (N = 35,983)			*Per-protocol analysis (N = 23,601)
	Total	HF cases, n (rate/10,000 person-years)	HR (95% CI)	Total	HF cases, n (rate/10,000 person-years)	HR (95% CI)
Overall
Control	17,960	381 (29.8)	1.00	11,993	190 (21.9)	1.00
CaD	18,023	363 (28.2)	0.95 (0.82 – 1.09)	11,608	188 (22.4)	1.02 (0.84 – 1.25)
Low-risk
Control	9,227	96 (11.7)	1.00	6,320	51 (11.0)	1.00
CaD	9,307	61 (7.0)	0.63 (0.46 – 0.87)	6,186	30 (6.6)	0.60 (0.38 – 0.94)
High-risk
Control	8,733	285 (46.9)	1.0	5,673	139 (34.4)	1.00
CaD	8,716	302 (49.5)	1.06 (0.90 – 1.24)	5,422	158 (40.9)	1.19 (0.95 – 1.49)

Abbreviations: CaD, calcium plus vitamin D trial; HR, hazard ratio; CI, confidence interval; CI, confidence interval; P, P value

^*Analysis are based on data from women with at least 80% adherence to study protocol