To measure the rate of non-publication and assess possible publication bias in clinical trials of electronic health records.
Methods
We searched ClinicalTrials.gov to identify registered clinical trials of electronic health records and searched the biomedical literature and contacted trial investigators to determine whether the results of the trials were published. Publications were judged as positive, negative, or neutral according to the primary outcome.
Results
Seventy-six percent of trials had publications describing trial results; of these, 74% were positive, 21% were neutral, and 4% were negative (harmful). Of unpublished studies for which the investigator responded, 43% were positive, 57% were neutral, and none were negative; the lower rate of positive results was significant (p < 0.001).
Conclusion
The rate of non-publication in electronic health record studies is similar to that in other biomedical studies. There appears to be a bias toward publication of positive trials in this domain.
Graphical abstract
Highlights
► We assessed publication bias in clinical trials of electronic health records. ► Of 62 trials, 76% had publications describing trial results; of these, 74% had positive results. ► Unpublished trials were less likely to have positive results compared to published trials. ► Publication bias could affect meta-analyses of EHR studies.