‘Salami Slicing’ Found in Analyses of Antipsychotic Trials

Evidence of duplicate publishing in articles analyzing data from clinical trials testing second-generation antipsychotics for depression


A new study, published in Psychotherapy and Psychosomatics, examines the prevalence of duplicate publications, or ‘salami slicing,’ in analyses of second-generation antipsychotic trials for depression. The results of the systematic review show widespread duplicate publishing and author financial conflicts of interest. The researchers, led by Glen Spielmans, professor of psychology at Metropolitan State University of Minnesota, write:

“Clinical trials serve as the bedrock of a publication strategy, yielding papers which are often widely cited, followed by secondary analyses, cumulatively providing the impression of a massive database of scientific support. Yet the decidedly overlapping nature of many secondary analyses suggests that the quantity of published analyses focusing on a drug does not offer a reasonable proxy for a drug’s actual efficacy or safety.”

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The researchers describesalami slicing’ as the practice of “publishing separate, yet similar pieces of a dataset in multiple papers.” They explain that this type of duplicate publication “can distort the medical literature by making a drug appear strongly supported based on the sheer volume of publications analyzing clinical trial data.” Pharmaceutical companies often pay “key opinion leaders” to author these publications in order to lend credibility to the article and market their drugs.

Many have critiqued the practice of salami slicing when it involves multiple publications from a single study. However, less attention has been paid to salami slicing that involves pooled analyses, where researchers combine results from multiple clinical trials into one large analysis. To address this, the researchers analyzed pooled analyses for clinical trials studying the efficacy of second-generation antipsychotics for depression.

The researchers identified 43 articles, 38 of which were funded by the pharmaceutical industry. Almost 90% of the authors of these articles had financial conflicts of interest, such as being an employee of the company that manufactures the drug being studied or receiving financial support from the pharmaceutical industry. Only two articles were independent of industry funding and had no authors with conflicts of interest. Thirty-four of the articles that were industry sponsored reported using a medical writer, who are often paid by industry and used to speed up the publication process.

Results show strong evidence of salami slicing as “several such analyses did not address unique research questions and/or provided very thin slices of data.” For example, at least 9 pooled analyses were written based on the same seven studies. In addition, 21 of the articles only reported on data from one or two clinical trials, a small number given that pooled analyses are designed to combine a large amount of data from multiple trials.

The researchers state, “We found that many pooled analyses regarding SGAs [second-generation antipsychotics] in the treatment of depression show substantial overlap. Overall, the included analyses could have been presented in a much smaller number of publications without losing valuable information.”

Antipsychotics are widely used as an adjunctive treatment for depression despite their significant side effects and a lack of clear evidence that they improve quality of life. Therefore, it is concerning that pharmaceutical industry may be artificially inflating the research literature on the efficacy of these medications for depression. The researchers write:

“Pharmaceutical companies design clinical trials, own the raw data from the trials, and analyze trial data. Through their own employees and/or contracted writers, drug firms greatly influence both the initial journal articles describing clinical trial results and a myriad of subsequent post hoc and pooled analyses.”

The authors caution against “marketing-based medicine,” as opposed to evidence-based medicine. They call for journal editors and peer reviewers, in addition to authors themselves, to end the practice of salami slicing.



Spielmans, G. I., Olson, S., & Keicher, R. M. (2017). “Salami slicing” in pooled analyses of second-generation antipsychotics for the treatment of depression. Psychotherapy and Psychosomatics, 86(3), 171-172. doi:10.1159/000464251 (Abstract)


  1. It is highly likely that a “depressed” person seeing a psychiatrist will be taking an antidepressant. Adding an antipsychotic, to an antidepressant, is already medically known (by all doctors with brains) to create “psychosis,” via anticholinergic toxidrome.

    “The symptoms of an anticholinergic toxidrome [can] include blurred vision, coma, decreased bowel sounds, delirium, dry skin, fever, flushing, hallucinations, ileus, memory loss, mydriasis (dilated pupils), myoclonus, psychosis, seizures, and urinary retention. Complications include hypertension, hyperthermia, and tachycardia. Substances that may cause this toxidrome include the four “anti’s of antihistamines, antipsychotics, antidepressants, and antiparkinsonian drugs[3] as well as atropine, benztropine, datura, and scopolamine.” From:


    But we already know the psychiatric industry does not know this (they would be the doctors without brains, or ethics), since the DSM recommended treatments for “bipolar” include combining the antidepressants and antipsychotics. So anticholinergic toxidrome, which should be included in the DSM but is NOT, induced “psychosis” will almost always be misdiagnosed by psychiatrists as one of the billable DSM disorders.

    For this reason it is highly likely adding an antipsychotic to an antidepressant will do substantially more harm, than good, to a “depressed” person. Of course, this also means most “bipolar” patients are actually dealing with an iatrogenic illness, as opposed to a “genetic” illness.

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  2. This is absolutely ridiculous. And yet, I am not the least bit surprised. “Depression” is still a very lucrative market, even though it seems that the emphasis until recently was on expanding “Bipolar Disorder” to include more and more people, who could then be prescribe more and more psychiatric drugs.

    I don’t think the psychiatrists alone are to blame for this. I forget the exact percentage, but the bulk of psych drug prescriptions are written by non-specialists. Family doctors, general practitioners, etc. certainly know that neuroleptics are very serious drugs with very serious adverse effect profiles, but many of them have chosen to dispense Latuda and friends to their patients as “treatment.” My best guess is that a lot of these unfortunate patients are female. A number of people who are given the neuroleptics have their “treatment” covered by Medicare or Medicaid, which brings in race and social class issues, also.

    I find it strange that the neuroleptics–which have long been known to cause intense misery (“neuroleptic-induced dysphoria,” akathisia, etc.)–are now being pushed on people who are so sad that they have been labaled with “depression.” It seems that these modern marvels don’t work all that well, either, which goes to show (once again…) the power of Big Pharma $$$ and “experts” to drive up drug costs, expose lots of people to unnecessary risks, and damage peoples’ lives, all to treat an “illness” that has yet to show up on brain scans, blood work, or even careful inspection at autopsy.

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    • Latuda is a frightening drug and I can’t believe it hasn’t been withdrawn. I’ve been off of it for more than a year now and I still struggle with temperature dysregulation on hot days. I suppose I’ll be lucky if that’s the worst lingering side/withdrawal effect from the many years of medications but I can’t believe it’s casually accepted. Especially given that the antidepressant effects of the drug quickly wear off, leading to massive dosages in attempts to chase the normal feeling. I’d call it the nastiest drug I’ve ever taken and the effects from it are what finally put me over the edge into the antipsychiatry camp. I’ll continue my one-woman crusade to call these drugs out as absolutely nothing more than poisons.

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  3. In studies of the second-generation “antipsychotic” drug (dis)Abilify, 25% of trial participants experienced akathisia after they started taking Abilify.

    “The most commonly observed adverse reactions (incidence greater than or equal to 5 percent and at least twice the incidence of placebo plus ADT) associated with the use of adjunctive ABILIFY were akathisia (25 percent vs 4 percent), restlessness (12 percent vs 2 percent) […]”

    Except restlessness is the hallmark feature of akathisia. I assume that the people with akathisia didn’t get a separate diagnosis of restlessness. That would be like diagnosing 25% with headache and 12% with pain in the cranium. So it’s possible that 37% suffered with akathisia, but some of them were labeled “restless” because it sounded better.

    Is there a black box warning for akathisia?

    If anything other than a “psychiatry” drug caused it, would the drug be approved?

    PS I’ve been putting “mental health” in quotation marks for a long time, and I rarely type the letters m-e-d-i-c-a-t-i-o-n in the order. From now on, “psychiatry” and related words will be in quotation marks, too.

    It works very well:

    I went to a psychiatrist and she said…
    I went to a “psychiatrist” and she said…

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  4. Why isn’t there a TV series, long running, about a brave, humane, kind psychologist who works in a clinic and tries to help people by talking with them about their fears and sadness? The brave psychologist could be the hero of the piece and he or she could also try to help the patients and inmates by getting them off of psychotropic drugs? There could be villains — psychiatrists who push drugs and ECT, and there could be romance (between psychologists, psychiatrists, and even patients/clients). It could be an ensemble series, sort of like The Good Wife, that ran 7 seasons. There could be plenty of drama, and there could be more than one hero/heroine. Maybe such a series could help publicize and further the idea of the need for change in the practice of psychiatry and mental hospitals. Of course, the series would need excellent actors and high production values, which would mean it would need much money. And I am sure big Pharma would not sponsor it.

    There could even be retrospective episodes to past decades or even historical eras: one history I remember reading was about a woman who had been institutionalized for over 30 years for psychosis and depression. Finally someone thought to do a blood workup and discovered she had extreme hypothyroidism and no one had ever thought to test her. Of course, when she was originally hospitalized, there were no blood tests for thyroid levels. All the pain and anguish modern psychiatry has caused needs to be publicized, even in a commercial product, like a TV series.

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    • “…when she was originally hospitalized there was no blood work done to test her thyroid levels.” This has actually happened to me on more than one occasion.

      It will never make a TV series. Whether Welton is serious or not, it would never make it past the panel of Big Pharma sponsors. Not only would they refuse to run Effexor commercials during the program (duh!) they would most likely threaten to take their business elsewhere.

      If there were hope for such a series it might consist of a bunch of comic sketches presented on YouTube or Vimeo. Sort of like The Onion.

      Nowadays such a production can be very low budget. If anyone else wanted to try this kind of thing, I can write the screenplays. Of course we also need actors, technicians, video editors, director, producer, etc.

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