To be eligible for the review, studies had to be randomised controlled trials (RCTs) that followed patients from the time of transplantation and compared treatment with control group. Transplants could be liver, heart, lung or kidney. Eligible trials had to assess fractures as an outcome, include participants over 18 years old, and could be of any sample size. Eligible treatments were oral or IV bisphosphonates (alendronate, risedronate, pamidronate, ibandronate, zoledronic acid) or active vitamin D analogues (calcitriol, calcidiol, 1alpha-hydroxyvitamin D). There were no dose restrictions. Trials of bone marrow transplantation or historical control studies were excluded.
The primary outcome was vertebral or non-vertebral fracture during the first year after transplantation. Change in areal bone mineral density was assessed in all trials as a secondary outcome.
Most included trials compared a bisphosphonate with placebo or no treatment; most trials administered treatment intravenously at various doses and timings. Trials of active vitamin D analogues were compared with no treatment. In all but one trial, participants received calcium supplements with or without vitamin D. Immunosuppressant regimen varied by type of organ transplanted but all included prednisone steroid treatment. In most trials there were no bone mineral density inclusion criteria. All trials assessed fractures using spine x-ray.
More than one researcher was involved in the process of selecting studies for the review.