Table 5

Participation of an epidemiologist/biostatistician and quality of multicentric studies

Epidemiologist/biostatistician
Yes % (n=112)No % (n=117)Crude OR (95% CI)Adjusted OR5-150 (95% CI)
Pre-study sample size estimation
  Yes55.642.91.7 (1.0, 2.8)1.6 (0.9, 2.7)
Inclusion/exclusion criteria
  Yes94.991.11.8 (0.7, 5.0)1.8 (0.6, 5.4)
Number of subjects asked for participation
  Yes34.236.60.9 (0.5, 1.5)0.9 (0.5, 1.5)
Number of subjects who agreed participation
  Yes23.130.40.7 (0.4, 1.2)0.7 (0.4, 1.2)
Blind randomisation
  Yes/not applicable40.331.31.5 (0.9, 2.5)1.5 (0.8, 2.6)
Assessment of baseline comparability of study groups
  Yes89.685.21.5 (0.7, 3.3)1.8 (0.8, 4.0)
Dates of starting/ending clinical trial
  Yes76.950.93.2 (1.8, 5.7)3.0 (1.7, 5.4)
Method to assess treatment compliance
  Yes53.041.11.6 (0.9, 2.7)1.4 (0.8, 2.5)
Masked assessment of outcome
  Yes56.451.81.2 (0.7, 2.0)1.1 (0.6, 1.9)
Outcome objectively assessed
  Yes91.584.81.9 (0.8, 4.3)1.9 (0.8, 4.5)
Existence of criteria to assess outcome
  Yes98.396.42.1 (0.3, 23.9)1.4 (0.2, 8.9)
Mentioning statistical procedures
  Yes99.297.33.2 (0.3, 169)2.0 (0.2, 22.6)
Analysis according to intention to treat
  Yes67.240.23.1 (1.8, 5.3)2.9 (1.6, 5.0)
Estimation of statistical power if results are non-significant
  Yes/not applicable89.788.41.1 (0.5, 2.6)1.2 (0.5, 2.8)
  • 5-150 Adjusted for funding and study sample size.