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Examining Bias in Published Surgical Glaucoma Clinical Trials
Reinemary Michael1, Hiuxin Zhang2, Sarah McIntyre2
1Department of Ophthalmology and ORL, Faculty of Medicine.
Journal of Glaucoma
|July 31, 2023
Summary
Most glaucoma surgery trials were unregistered, but publication bias was low. However, registered trials showed outcome reporting bias, highlighting the need for full trial registration for transparency and better patient care.
Area of Science:
- Ophthalmology
- Clinical Trials
- Surgical Innovation
Background:
- Randomized controlled trials (RCTs) are crucial for high-quality evidence in glaucoma surgery.
- Biases in RCTs can limit the applicability of findings.
- Investigating publication bias (PB) and outcome reporting bias (ORB) in glaucoma surgical trials is essential.
Approach:
- A comprehensive literature review of MEDLINE, EMBASE, and CENTRAL databases was performed.
- Included were RCTs published between 2007-2021 on surgical glaucoma treatments.
- Assessed were trial registration status, PB, ORB, and study quality (Jadad score).
Key Points:
- 63% of 161 included RCTs were not registered; 47% reported statistically significant results.
- Publication bias was not evident, but 37% of registered trials exhibited outcome reporting bias.
- Unregistered trials generally had lower methodological quality.
Conclusions:
- While publication bias is not prominent in glaucoma surgical trials, outcome reporting bias is a concern in registered studies.
- Full trial registration is vital for transparent interpretation, improved surgical patient care, and informed clinical decision-making.
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