Systematic Review of Commercial Funding for Observational Studies and Clinical Trials

In recent reviews regarding the effect of dietary cholesterol on blood cholesterol concentrations, the majority of included studies have been funded by the egg industry. The current review will assess trends over time in industry funding for such studies. 

Systematic Review Registration

This review was submitted for registration on PROSPERO. Because the study focused on funding sources rather than clinical outcomes, PROSPERO did not register the review. 

Objective

This study aims to answer the question: Among studies assessing the effects of eggs on blood cholesterol concentrations, has the number or proportion of industry-funded studies increased over time? 

Hypothesis

We hypothesize that industry funding has increased over time.  

Need for Review

A search of the Cochrane Database of Systematic Reviews (CDSR, Cochrane Database of Systematic Reviews (CDSR)) on August 30, 2015, using the search field “Title, Abstract, Keywords” with the search term “egg” produced 62 records, none of which related to industry funding. With the search field “source,” the same search term produced no records. 

Study outcomes

Evidence on trends in industry funding for studies related to the effects of eggs on blood cholesterol concentrations.

Exposures and Comparator

This study does not seek to determine the effects of egg ingestion on blood cholesterol. It is limited to ascertaining industry funding.  

Types of studies included

Observational studies, intervention trials, and reviews 

Study populations

Adult humans, without regard to gender, race, or ethnicity. 

Languages

All 

Publication status and date

Studies are eligible regardless of publication status or publication date, through August 2015, provided adequate details are available. The year 2015 was selected as the cutoff date because that was the year of the most recent Dietary Guidelines Advisory Committee report. 

Study duration

There are no limits on intervention periods. 

Study cataloguing

References will be maintained using EndNote. 

Databases to be searched

PubMed

Cochrane Central Register of Controlled Trials 

Search Terms

We will search as broadly as possible, using the terms “egg” AND “cholesterol”

Limits

Humans