Subgroup analysis for vertebral fractures and percent change of lumbar spine BMD at different time-points.

N.A.: not available, N.S.: no significant between the two group, WMD: weighted mean difference, 95%CI: 95% confidential interval.
M stands for manner, M1:prevention manner, M2:treatment manner; U stands for usage, U1: continuous therapy of BPs, U 2: intermittent therapy of BPs; G stands for generation, G1: the first generation of BPs, G2: the second and third generation of BPs; Ca stands for calcium, Ca1: supplemented with calcium, Ca2: not supplemented with calcium; RA: only RA patients were included, RD: patients with all sort of rheumatic diseases were included; in mean age, Age1 : more than 50 years, Age2: less than 50 years; in Jadad score, High: ≥3 points, Low: <3 points; B stands for blinding, B1: blinding to patients; B2: not blinding to patients.