Table 1

Participant and follow-up characteristics

Non-operative controlPlacebo controlP value
N3861
Age of study cohorts (mean±SD, n)
 Surgical intervention group54.8±12.6, n=3450.4±13.4, n=550.125
 Control group55.1±13.0, n=3450.5±13.3, n=550.114
 Other group*48±8, n=347.8±5.8, n=40.807
Gender of study cohorts (mean+SD)
 Per cent female62.7±24.861.8±30.90.87
Follow-up characteristics (median (IQR))
 Number of timepoints†3 (2–5)4 (2–6)0.412
 Timepoint (primary outcome), days365 (183–730)274 (91–365)0.006
 Timepoint (longest), days365 (365–730)365 (183–730)0.193
  • *Other group only applicable to trials incorporating three treatment arms.

  • †Number of follow-up points was not available for five studies (one non-operative control and four placebo).

  • N, number of studies.