CSPI identifies bias in medical literature on pediatric antidepressants
A new study of medical journal reports on the effectiveness of antidepressants in children shows that drug industry-funded research is much more likely to be positive than independently-funded research, and both are far more positive than the Food and Drug Administration’s (FDA) assessment of the drugs’ tests.
The Center for Science in the Public Interest found that 96 percent of the industry-funded efficacy studies of drugs like Prozac, Zoloft, and Paxil in children were positive. That compares to just 63 percent of independently funded studies published in medical journals.
If one looks at just published clinical trials that contained a placebo-controlled arm, industry-funded clinicians reported the drugs were effective in 9 out of 10 cases. But among researchers not funded by industry, only 5 out of 9 reported positive results, which is surprisingly low given that other studies have shown that medical journals are biased toward publishing positive reports. By comparison, just 3 of 15 FDA reviews of pediatric antidepressant trials, many of which have not been published, were positive.
"Regrettably, drug companies see medical journals as just another cog in their public relations machine," said Merrill Goozner, director of the CSPI Integrity in Science Project. "Industry funding has skewed the published literature and through that medical opinion on the use of these drugs in kids."
Prozac, Zoloft, and Paxil are among a class of antidepressants known as selective seratonin reuptake inhibitors (SSRIs). A joint meeting of the FDA’s Psychopharmacologic and Pediatric Advisory Committees is meeting on Monday to discuss the possible connection between this class of drugs and suicide in youths. As the FDA reviewer pointed out in his review before today’s meeting, "Ultimately, this is a risk benefit assessment, so it is important to know where we stand on the benefit side of the issue."
While most researchers believe their funding source does not influence their results, this study echoes numerous previous studies finding that published research that is industry-funded is much more likely to show results favorable to the sponsor than independent research funded by either government or academic institutions.
"The pharmaceutical industry’s domination of this field of research has biased the published record," Goozner said. "That fact should be taken into account when evaluating the alleged benefits of these drugs versus their potential risks."