External Validity of Randomized Controlled Trials in Primary Care
Author Information
Author(s): Ritu Jones, Robert O. Jones, Colin McCowan, Alan A. Montgomery, Tom Fahey
Primary Institution: University of Dundee
Hypothesis
Do published primary care-based RCTs report sufficient information about their study sample assembly and is this associated with RCT characteristics?
Conclusion
RCTs in primary care suggest that eligible patients are likely to be randomized, but many do not provide enough information about the recruitment process.
Supporting Evidence
- 70% of RCTs reported the number of individuals assessed for eligibility.
- 80% reported the number eligible for participation.
- Median eligibility fraction was 83% and median enrolment fraction was 74%.
- Median number needed to screen (NNS) was 2.43.
Takeaway
This study looked at how well trials in family medicine report who they include in their research. It found that many trials don't share enough details about how they picked their participants.
Methodology
Reviewed RCTs published in four primary care journals from 2001 to 2004, focusing on recruitment data.
Potential Biases
Potential under-reporting of recruitment processes may lead to biased conclusions about external validity.
Limitations
The study only included RCTs from specific primary care journals, which may not represent all primary care research.
Participant Demographics
Majority of RCTs originated from the UK, with some from the US and the Netherlands; most were multi-centre.
Digital Object Identifier (DOI)
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