Fraud, errors, and falsified data winds its way into the smallest niche publications, as well the most prestigious journals with the greatest impact factors. But the ones who get caught are generally the most egregious offenders, like a young researcher in Japan who published “game changing” results on stem cells that didn’t exist.

But how many studies with less bold claims fly under the radar, and are never caught by an editor or a peer reviewer?

Many, answers a new statistical analysis of thousands of studies in eight prestigious journals, published this week.

The statistical analysis of 5,087 randomized, controlled trials turned up dozens that data had to be skewed for the end result, according to John Carlisle, the author of the paper in the journal Anaesthesia.

“Fraud, unintentional error, correlation, stratified allocation and poor methodology might have contributed to the excess of randomized, controlled trials with similar or dissimilar means, a pattern that was common to all the surveyed journals,” writes Carlisle.

“It is likely that this work will lead to the identification, correction and retraction of hitherto unretracted randomized, controlled trials,” he adds.

The thousands of studies were published between January 2000 and December 2015 in eight journals. Six of them are specialty medical journals: Anaesthesia itself, Anesthesia and Analgesia, Anesthesiology, the British Journal of Anaesthesia, the Canadian Journal of Anaesthesia, the European Journal of Anaesthesiology.

The remaining two are the giants Journal of the American Medical Association and the New England Journal of Medicine.

Of the 5,087 studies, 72 had already been retracted. But Carlisle’s statistical analysis found that 43 more almost certainly contained problematic data and results.

Those 43 trials included baseline variables that were so tailored to the end results, that the likelihood of reaching them randomly was the same as finding “one water drop in 20,000 Olympic-sized swimming pools,” according to the study.

Among the authors were the names of three anesthesiologists who had previously been discredited: Scott Reuben, a Massachusetts pain specialist who even served some federal prison time; Joachim Boldt, a German who had more than 80 papers retracted; and Yoshitaka Fujii, the world recordholder with 183 papers retracted. (Fujii’s falsifications were found through previous analyses made by Carlisle, an anesthesiologist at Torbay Hospital in the United Kingdom).

The pressures of “publish or perish” have affected American researchers – but also international scientists. Some major publishers have been victims to a corrupted peer-review process, one of the latest being Springer, which retracted 107 studies published by its journal Tumor Biology.