Figure 3. Summarized results for the longevity of the effect from conventional subgroup analysis and trial sequential analysis by follow-up duration. *(A) Conventional subgroup meta-analysis; (B) Trial sequential analysis for subgroups of bisphosphonate treatment duration; (C) Post-treatment 1-2 years; (D) Post-treatment 3-4 years and (E) Post-treatment >4 years. *In these analyses, we included only RCTs and excluded all the cohort studies, because that the duration of bisphosphonate treatment was not identical for bisphosphonate users in each individual cohort study and none of them reported a clear and explicit treatment duration.