A systematic search for reports of site monitoring technique comparisons in clinical trials

As part of a broader methodological programme of work around clinical trial monitoring, we wanted to evaluate the existing evidence for the effectiveness of different monitoring techniques.

To identify and evaluate prospective studies of the effectiveness of different monitoring strategies.

A systematic search of MEDLINE from 1950 onwards, using free-text terms to identify relevant published studies. We intended to extract data on details of comparative techniques, monitoring findings identified by different techniques, and recommendations or identification of areas in need of further research made by authors.

A total of 1222 published abstracts were identified and reviewed. Of these, nine articles described methods for quality control (QC) of clinical trial activities, and one article was identified that compared the same monitoring technique at two timepoints. None included a direct comparison of different monitoring techniques and findings.

The search strategy was limited to MEDLINE. However, MEDLINE includes all the journals that tend to report trial methodological research.

There is a lack of published empirical data that compare monitoring strategies prospectively. Assessment of the usefulness and cost-effectiveness of monitoring techniques in a variety of clinical trial settings and indications is needed.