Suspect Science: The Top 5 Retracted Papers of 2015
Credit: Looker_Studio/Shutterstock.com

The scientific method is a painstaking process of observing nature, asking questions, formulating testable hypotheses, conducting experiments and collecting data … and then sometimes just making stuff up when reality doesn't match your expectations.

Or maybe it just seems that way when you're reading through the retraction notices that scientific journals are posting with greater and greater frequency. There has been a 10-fold increase in the percentage of scientific papers retracted because of fraud since 1975, according to a study published in 2012 in the journal Proceedings of the National Academy of Sciences.

Among the more than 2,000 retracted life science papers that researchers reviewed in this study, only about 20 percent were retracted because of honest errors. A whopping 70 percent were pulled as a result of scientific misconduct — that is, lying, cheating and/or stealing.

A retraction implies that the paper is flawed, that it should never have been published and that the presented results shouldn't be considered trustworthy. Unfortunately, while you can scrub a paper from a journal, you can't always erase it from public consciousness. One of the most notorious papers that has been retracted is the fraudulent 1998 study by Andrew Wakefield proposing that the MMR vaccine might cause autism.

A blog called Retraction Watch follows the occasionally humorous — and sometimes scandalous — world of scientific retractions in great detail. Below are some notable retractions from 2015, some inspired by Retraction Watch.

5. Plagiarism guidelines retracted for … plagiarism

You can add this one to annals of irony, along with the fire station that burnt down. The Indian Journal of Dermatology wanted to take a tough stance against plagiarism, but the editors hardly scratched the surface with a paper containing a set of plagiarism guidelines for scientists.The paper was "written" by Indian researcher Thorakkal Shamim, but it contained a generous amount of text lifted from a dissertation by an Iranian graduate student named Mehdi Mokhtari.

Apparently, several years ago, Mokhtari had sent Shamim, an international expert on plagiarism, a series of questionnaires to gather information he needed for his dissertation, according to Retraction Watch. It was the first of these questionnaires that became the basis of Shamim's article. One of Mokhtari's professors, Kamran Yazdani, noticed the act of plagiarism, and the journal promptly retracted this piece in March 2015. [Understanding the 10 Most Destructive Human Behaviors]

4. Nein, Nicht Mit Meinem Software (No, Not with My Software!)

Sometimes papers are retracted not for scientific misconduct but rather for what a journal considers to be poor sportsmanship. That seems to have been the case when the publisher BioMed Central retracted a paper by German scientist Gangolf Jobb after he announced on his website that, as of October 2015, he would no longer license his software for use by scientists working in countries that he deemed to be too friendly to immigrants. Irony alert: The software, called Treefinder, tracks the evolutionary relationships among species — relationships that exist, of course, because nature knows no borders.

Immigrant-friendly countries, in Jobb's mind, include France, Great Britain and the fatherland, Germany. What about the United States? Jobb banned U.S. scientists from using the software back in February 2015, citing U.S. imperialism.

Jobb described his software in a 2004 article in the journal BMC Evolutionary Biology. The paper has been cited hundreds of times by other scientists, a clear indication of its importance to the field of evolutionary biology. But Jobb's October announcement — affecting scientists also in Austria, Belgium, Denmark, the Netherlands and Sweden (but mercifully sparing Lichtenstein) — was the last straw for BioMed Central. The publisher's retraction notice states that Jobb's decision "breaches the journal's editorial policy on software availability which has been in effect since the time of publication."

In his defense, Jobb explains on his website that it is his software; he can license it any way he pleases; and he is frustrated by the current academic culture, which he thinks makes it difficult for young researchers to establish a career and make a decent living. Scientists residing in the offending countries can still use the software, Jobb explains. They merely need to (warning, irony alert #2) move to a country less accepting of immigrants.

3. Grizzly details of bears with diabetes

Grizzly bears become diabetics during hibernation, which enables them to survive on the fat reserves they accumulate in the summer and fall … maybe. The fascinating and widely reported results of this study, published in the prestigious journal Cell Metabolism, are now being called into question with the revelation that one study author at the biotech company Amgen manipulated data.

The journal retracted the article in September 2015 at Amgen's request. Six of the paper's 12 authors are from Amgen, including senior author Kevin Corbit, and it is not clear who the offending person was; the retraction notice merely says that that person "is no longer employed by Amgen." The Wall Street Journal reported that Corbit was let go from Amgen for fabricating data on what Corbit himself described as "another matter."

Amgen is concerned about this, and The Wall Street Journal is reporting on this, because the findings, if true, could have significant implications for understanding both the evolutionary cause for diabetes and a drug pathway to treat it. The co-authors on the study from Washington State University and the University of Idaho have said they remain confident of the core result and are now repeating the study. The outcome certainly bears watching. [Gallery: Polar Bears Swimming in the Arctic Ocean]

2. Shroud lifted on colorful Italian engineer

Alberto Carpinteri hasn't garnered much international attention, but he's infamous in Italy for a series of fantastical papers with topics as disparate as the Shroud of Turin and cold fusion.

As the director of the Italian National Institute of Metrological Research (INRIM) in Turin, Carpinteri had planned to put some of his institution's funding toward a disputed form of nuclear fission called piezonuclear, in which compressing solids can result in nuclear fission without producing nuclear waste or gamma rays. More than 1,000 scientists disagreed with the idea, and the Italian government backed down from funding the project, as reported in 2012 in the journal Nature.

Those dissenting scientists may be reassured by the fact that 11 of Carpinteri's papers were retracted this year. All are from a journal Carpinteri once edited, called Meccanica, and, according to the retraction notices, all have been pulled because "the editorial process had been compromised." Among the papers were four that support the theory of piezonuclear energy, including one that attempted to marry the piezonuclear concept with the similarly disputed theory of cold fusion: "Cold Nuclear Fusion Explained by Hydrogen Embrittlement and Piezonuclear Fissions in Metallic Electrodes."

Among the more widely reported of Carpinteri's retracted studies was his revelation that the Shroud of Turin — a piece of linen that some believe was the burial shroud of Jesus, but which, based on radiocarbon dating, appears to be from the 13th century — does indeed date back to the year of Jesus' death in 33 A.D. Carpinteri claimed to have determined that an earthquake in 33 A.D. of at least 8.3 magnitude could have generated neutron radiation from the earth's crust (again, based on the piezonuclear theory) to produce the image from the crucified man's body. The same earthquake would have increased the amount of carbon-14 isotopes found on the linen, thus throwing off the radiocarbon dating, he said.

No word yet on whether cold fusion could have produced the shroud's image.

1. Gay canvassers change minds

The highest-profile retraction of 2015 comes from the journal Science, for a paper stating that gay door-to-door canvassers could sway the opinions of voters who are opposed to same-sex marriage with just a short, face-to-face discussion about the issue. [I Don't: 5 Myths About Marriage]

It's worth noting up front that most results from psychology-based studies either can't be reproduced or are flat-out wrong. That's not an opinion, but actually the result of a study published in August 2015 in Science — by psychologists! — that found the majority of published psychology studies are plagued by poor methodology and statistics. If the results sound too good to be true, they probably aren't.

The study on gay canvassers, published in December 2014, made the remarkable suggestion that long-standing bias and prejudice could be overturned in just a few minutes of conversation. As such, the results were widely reported in the news media, including Live Science. But the whole thing had imploded by May 2015, when other researchers not only couldn't replicate the study but also found evidence that the data were cooked.

The first author, Michael LaCour, was a graduate student at the University of California, Los Angeles, and the study was his graduate thesis. The senior author was LaCour's advisor at Columbia University, Donald Green. Green called for the retraction once he learned that LaCour couldn't provide him with much of the raw data in question. "There was a mountain of fabrication," Green told The Huffington Post in May, distancing himself from the work.

Prior to the retraction, Princeton University had offered LaCour a position as an assistant professor, but it has since revoked that offer. LaCour subsequently told the New York Times that he may have erred in methodology, but not in the results.

In any case, it likely will take more than a short conversation to convince skeptics that most psychology studies are robust.

Follow Christopher Wanjek @wanjek for daily tweets on health and science with a humorous edge. Wanjek is the author of "Food at Work" and "Bad Medicine." His column, Bad Medicine, appears regularly on Live Science.