Original articleDiscrepancy between Results and Abstract Conclusions in Industry- vs Nonindustry-funded Studies Comparing Topical Prostaglandins
Section snippets
Methods
A MEDLINE search from 1966 to the second week of November 2007 using any combination of the keywords latanoprost, travoprost, and bimatoprost was conducted. The title and abstracts from the initial search were reviewed and those included were English language publications comparing the intraocular pressure (IOP)-lowering efficacy of any combination of latanoprost; travoprost; or bimatoprost. The complete articles were obtained and the references also were searched to identify relevant
Results
A total of 180 articles were identified by the original search. After reviewing the abstracts, 39 met the inclusion criteria and were included in the study. In reviewing the references of these publications, no additional publications were found. Of the 39 publications, 35 were studies that directly compared two or three of the PGAs and four were meta-analyses. Thirty-five of the publications included a disclosure statement, and four had no documented disclosure. The authors were contacted
Discussion
We found that 62% of the industry-funded vs none of the nonindustry-funded studies' abstract conclusions did not correspond with the results of the main outcome measure (P = .0006, Fisher exact test). Although only 24% of the industry-funded publications had a statistically significant main outcome measure, 90% of the industry funded studies had a proindustry abstract conclusion.
The influence of industry on publications involving a wide range of diseases and drugs is well documented.2, 5, 6, 7,
Dr Yvonne Buys completed her MD, ophthalmology residency, and glaucoma fellowship at the University of Toronto, Toronto, Canada. She is currently an Associate Professor at the University of Toronto, Department of Ophthalmology, Co-Director of the Glaucoma Unit at the University Health Network, and President of the Canadian Glaucoma Society. Dr Buys is involved in training ophthalmology residents and glaucoma fellows. She has published over 60 peer-reviewed papers and three book chapters in the
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Cited by (0)
Dr Yvonne Buys completed her MD, ophthalmology residency, and glaucoma fellowship at the University of Toronto, Toronto, Canada. She is currently an Associate Professor at the University of Toronto, Department of Ophthalmology, Co-Director of the Glaucoma Unit at the University Health Network, and President of the Canadian Glaucoma Society. Dr Buys is involved in training ophthalmology residents and glaucoma fellows. She has published over 60 peer-reviewed papers and three book chapters in the area of glaucoma.
Dr Tariq Alasbali completed his MD, ophthalmology residency at King Faisal University and a glaucoma fellowship at King Khaled Eye Specialist Hospital (KKESH) in Saudi Arabia. Dr Alasbali completed a research fellowship and currently he is a clinical glaucoma fellow at the University of Toronto, Department of Ophthalmology. Dr Alasbali received a Canadian Ophthalmological Society award for excellence in ophthalmic research in 2007.
See accompanying Editorial on page 1.