Table 2.

Fracture rates

GR vs. other patients
	GR patients			Other patients
	n = 2,726			n = 2,726			IRR (95% CI)a,b Unadjusted
	Total number of fractures	Total patient-years of observation	IR of fractures, per 1,000 patient-years	Total number of fractures	Total patient-years of observation	IR of fractures, per 1,000 patient-years
Any site	409	11,804	34.65	540	12,818	42.13	0.83 (0.70–0.97)*
Hip	100	11,804	8.47	114	12,818	8.89	0.98 (0.69–1.40)
Pelvis	28	11,804	2.37	43	12,818	3.35	0.71 (0.41–1.23)
Spine	128	11,804	10.84	194	12,818	15.13	0.71 (0.54–0.95)*
Wrist/arm	180	11,804	15.25	215	12,818	16.77	0.91 (0.73–1.13)
GR vs. alendronate patients
	GR patients			Alendronate patients
	n = 1,807			n = 1,807			IRR (95% CI)a,b Unadjusted
	Total number of fractures	Total patient-years of observation	IR of fractures, per 1,000 patient-years	Total number of fractures	Total patient-years of observation	IR of fractures, per 1,000 patient-years
Any site	262	7,712	33.97	354	8,323	42.53	0.81 (0.66–0.98)*
Hip	71	7,712	9.21	80	8,323	9.61	0.99 (0.65–1.51)
Pelvis	16	7,712	2.07	26	8,323	3.12	0.68 (0.35–1.33)
Spine	83	7,712	10.76	132	8,323	15.86	0.69 (0.49–0.97)*
Wrist/arm	112	7,712	14.52	132	8,323	15.86	0.91 (0.70–1.20)

Notes:

CI confidence interval, IR incidence rate, IRR incidence rate ratio

^aIncidence rate ratios were estimated with generalized linear models with log link and negative binomial distribution with robust error variances to account for the matched pairs. Incidence rate ratios may differ from the ratio of the incidence rates because of adjustments for overdispersion

^bAn IRR < 1 indicates a lower incidence of fracture per patient-year among women treated with risedronate GR

^*Significant at the 5% level