Contamination and drop-out rate in the control group by (B) intervention during and (C) after study intervention period.

a. Intervention for control group included: information about exercise, education (session) unrelated to exercises, keep exercise diary, use pedometers or accelerometers, phone calls unrelated to exercise, alternative intervention.
b. Study intervention was (partially) offered to control group after study intervention period, or information about exercise or exercise prescriptions were offered to control group after study intervention period.
c. For contamination data are given in number (percentages) of studies that reported contamination.
Contamination was reported in 30/40 (75%) studies.
d. For drop-out rates data are given in mean ± standard deviation of studies that reported drop-out. Drop-out rates were reported in 36/40 (90%) studies.
e. Excess drop-out rate = drop-out rate control group—drop-out rate exercise group.
Contamination and drop-out rate in the control group by (B) intervention during and (C) after study intervention period.