Fig 1.
Illustration of the four-state model.
The boxes indicate the states, the arrows the possible state transitions.
Fig 2.
Flowchart of study protocols approved between 2000 and 2002 by the research ethics committee of the University of Freiburg/Germany.
*We included one additional study compared to our previous analyses [24], because it later turned out that the survey results were incorrect (study started at local study site).
Table 1.
Baseline characteristics of included studies (n = 806).
Fig 3.
The numbers next to the arrows indicate the total numbers of studies for each transition.
Fig 4.
Complement of Kaplan-Meier estimate with its 95% confidence interval of the cumulative distribution function of the total time to publication.
Time point 0 is the REC’s positive vote, i.e. study approval.
Table 2.
Estimated covariate effects with their 95% confidence intervals (two-state model).
Table 3.
Estimated covariate effects with their 95% confidence intervals (four-state model).