TABLE 3. Summary of Study Quality of Articles Included in This Systematic Review.

Study	Control Selection	Comparability of Cases and Controls at Baseline	Verification of Fractures	Control for the Potential Confounding Effects of Body Size	Temporality Ensured (ie, Bone Density Measured Before Fracture Occurred)	Multiple Comparisons and Subgroup Analyses Carried out
Landin and Nilsson14 (1982)	Neighborhood controls	Unknown	Unknown	Attempted	No	No
Chan et al15(1984)	Unknown	Difference in weight between cases and controls	Radiograph review	No difference found in height	No	No
Cook et al16(1987)	Unknown	Good	Unknown	No difference found in height or weight	No	No
Goulding et al17 (1998)	Neighborhood controls	Difference in weight between cases and controls	Radiograph review	No difference found in height	No	Yes
Skaggs and Loro18 (2001)	Neighborhood controls	Good	Unknown	Attempted	No	No
Ma and Jones19 (2002)	From previously recruited cohorts	Good	Radiograph review	Attempted	No	No
Suuriniemi et al20 (2003)	From previously recruited cohorts	Good	Radiograph review	Attempted	No	Yes
Ma and Jones21 (2003)	Neighborhood controls	Good	Radiograph review	Attempted	No	Yes
Schalamon et al22 (2004)	Neighborhood controls	Unknown	Unknown	No difference found in height or weight	No	No
Goulding et al23 (2004)	From previously recruited cohorts	Good	Radiograph review	Attempted	No	No