A reanalysis of data from a controversial 2001 study that opened the doors for doctors to write millions of prescriptions of an antidepressant to children and teenagers shows that the drug is not only ineffective but potentially unsafe. The new study, published in the BMJ, details a number of issues with the original analysis that made paroxetine, marketed as Paxil by GlaxoSmithKline, look more favorable. Here's what you need to know about the findings:

Q: Tell me about the old study.

A: Published in the Journal of the American Academy of Child and Adolescent Psychiatry and known as Study 329, it purportedly showed that the drug is safe and effective in adolescents with depression. The study has been revealed to have been largely ghostwritten by a consultant on the drugmaker's payroll. The Food and Drug Administration has required so-called "black box" warnings on the packaging since 2004 after it received reports of links to suicidal thinking. The company has also faced consumer lawsuits by parents of teens who said their children had serious reactions to the drug.

Q: What's the new study?

A: The team conducting the reanalysis — led by Jon Jureidini, a professor at the University of Adelaide in Australia — went back to the raw data and came to starkly different conclusions. They found that the effect of the drug was no different from a placebo and that there was an increase in harms among study participants, the most alarming of which was an increase in suicidal thoughts and behavior. Jureidini and his colleagues said that Study 329 contained numerous transcription errors and other problems that masked issues and violated the company's protocols for statistical analysis.

Q: What is GlaxoSmithKline's take?

A: When the study was published, the company said: "We were able to help this team to carry out their reanalysis by providing access to the detailed data from the original trial. This reflects our commitment to data transparency — we publish the results of all our studies regardless of whether they are positive or negative. … We have also led the way in giving external researchers access to the very detailed patient-level data behind our studies, granting access to more than 50 research teams around the world so they can independently use our data."

Q: How common is it for researchers to reanalyze the data for a published study?

A: This happens very rarely and part of the reason is that it's often difficult for outside researchers to get the raw data. The study was part of an initiative that "encourages abandoned or misreported studies to be published or formally corrected to ensure doctors and patients have complete and accurate information." Peter Doshi, an assistant professor at the University of Maryland School of Pharmacy and an associate editor of the BMJ, said the reanalysis is a "model for the future of publishing" that makes the data public.

Washington Post