Characteristics | No. of trials, m | Fitted mean | 95% CI | F test | p value |
---|---|---|---|---|---|
Inclusion criteria | |||||
Gender | 527 | 2.58 | 0.0769 | ||
Both | 33.38 | (25.76–43.24) | |||
Female | 24.84 | (15.86–38.90) | |||
Male | 20.84 | (11.72–37.07) | |||
Age categoriesa | 527 | 1.18 | 0.3184 | ||
Children only | 27.82 | (18.67–41.46) | 41.46 | ||
Adults only | 35.18 | (23.20–53.36) | 53.36 | ||
Elderly only | 56.05 | (31.69–99.15) | 99.15 | ||
Children and adults | 30.30 | (19.48–47.12) | 47.12 | ||
Children to elderly | 33.60 | (24.87–45.40) | 45.4 | ||
Adults to elderly | 32.37 | (24.50–42.78) | 42.78 | ||
Study designs | |||||
Has DMC?b | 450 | 0.01 | 0.9328 | ||
No | 31.87 | (24.29–41.82) | |||
Yes | 32.11 | (24.24–42.54) | |||
FDA regulated intervention?c | 514 | 1.94 | 0.1647 | ||
No | 35.79 | (27.16–47.16) | |||
Yes | 31.87 | (24.33–41.75) | |||
Interventions, facilities and authorities | |||||
Lead sponsor | 527 | 4.49 | 0.004 | ||
US Federal | 125.86 | (49.53–319.80) | |||
Industry | 31.99 | (24.19–42.31) | |||
NIH | 55.42 | (31.66–97.02) | |||
Other | 31.85 | (24.44–41.50) | |||
Trial location | 527 | 5.14 | 0.0017 | ||
US only | 27.35 | (20.71–36.11) | |||
EU only | 50.43 | (35.66–71.32) | |||
US and EU | 34.32 | (22.45–52.48) | |||
Single European country | 27.81 | (20.89–37.03) | |||
No. of countries involved in the trial | 527 | 1.12d | (1.07–1.18) | 19.58 | <.0001 |
Year that enrolment to the protocol begins | 523 | 4.90 | 0.0002 | ||
< 1990 | 313.70 | (53.14–1852.05) | |||
1990–1999 | 26.44 | (13.53–51.68) | |||
2000–2004 | 50.47 | (36.25–70.28) | |||
2005–2009 | 29.75 | (22.55–39.25) | |||
2010–2014 | 31.15 | (23.99–40.46) | |||
2015 and after | 35.79 | (21.68–59.08) |