Table 2.

Methodological Quality of the Ten Included Clinical Trials

Study quality criteria	Monreal 199454	Bernis 199746 *	FRISC II 199947	Veiga 200056	Lai 200153	Grassman 200148	Hull 200750,51 †	Hull 200952	Haas 201249	Serra 201355
Adequate randomization	Yes	Unclear	Yes	Yes	No	Unclear	Yes	Yes	Yes	Unclear
Concealed allocation	Unclear	Unclear	Yes	Yes	No	Yes	Yes	Yes	Yes	No
Prognostic factor balance at baseline for the primary disease	Yes	Unclear	Yes	No	No	Yes	No	No	No	No
Blinding of participants	No	Unclear	Yes	No	Yes	Yes	No	No	Yes	No
Blinding of healthcare providers	Yes	Unclear	Yes	No	No	Yes	No	No	Yes	No
Blinding of outcome assessor	Yes	Unclear	Yes	Yes	No	Unclear	No	No	Yes	No
Co-intervention similar	Yes	Unclear	Yes	Yes	Yes	Unclear	Yes	Yes	Yes	Yes
Acceptable compliance in both groups	Unclear	Unclear	Unclear	Yes	Yes	Unclear	Unclear	Unclear	Unclear	Unclear
Drop-out rate described and acceptable (<10 %)	Yes	Unclear	Yes	Yes	No	No	Yes	Yes	Yes	Yes
Comparable timing of the primary outcome assessment in both groups	Yes	Unclear	Yes	Yes	Yes	Yes	Yes	Yes	Yes	Yes
Intention to treat analysis	Yes	Unclear	Yes	Yes	No	Unclear	Yes	Yes	No	Yes
Van Tulder internal validity score	8/11	NA	10/11	8/11	4/11	5/11	6/11	6/11	8/11	4/11
Additional criterion 1: prognostic factor balance at baseline for osteoporosis	Yes	Unclear	Unclear	Unclear	Yes	Yes	No	Unclear	No	Unclear
Additional criterion 2: contamination, use of heparin in both intervention groups	No	Unclear	No	No	No	No	No	Yes	No	No
Additional criterion 3: comparable timing of bone outcome assessment in both groups	Yes	Unclear	Unclear	Yes	Yes	Yes	Yes	Yes	Yes	Unclear
Additional criterion 4: if fracture was assessed among adverse events, was duration of follow-up to detect a fracture adequate (≥1 year)	No	Unclear	No	Yes	NA	NA	Yes	Yes	No	NA
Additional criterion 5: sample large enough to detect differences between the groups regarding fracture outcome	No	Unclear	Yes	No	No	No	No	No	No	No
Additional criterion 6: bone outcomes assessed as secondary	Yes	Unclear	Yes	Yes	No	Yes	Yes	Yes	Yes	Yes

^*Study by Bernis et al.⁴⁶ was reported as abstract and was rated unclear; ^†two published articles^{50 , 51} represent the data of the same study.