BOSTON, Jan. 10 (UPI) -- Boston researchers found beverage studies funded solely by industry were four to eight times more likely to have conclusions favorable to sponsors.
Senior author David Ludwig of Children's Hospital Boston believes that bias in nutrition studies may have far greater effects than bias in pharmaceutical studies.
Because the researchers focused their analysis on soft drinks, juice and milk, they say they aren't sure whether their findings extend to nutrition studies as a whole.
"We chose beverages because they represent an area of nutrition that's very controversial, that's relevant to children and involves a part of the food industry that is highly profitable and where research findings could have direct financial implications," Ludwig says.
The researchers examined the scientific literature on more than 200 papers about soft drinks, juice and milk published from 1999 to 2003.
Interventional studies with all-industry funding were much less likely to have unfavorable conclusions than those with no industry funding, according to Ludwig.
Among all types of studies, comparing all-industry versus no-industry funding, the odds ratio for having a favorable versus unfavorable conclusion was 4.37, increasing to 7.61 when beverage type, publication year and examination of authors' personal conflicts of interest were taken into account, says the review published in the journal PLoS Medicine.
