Funding bias
Encyclopedia
The terms funding bias, sponsorship bias, funding outcome bias, or funding publication bias refer to an observed tendency of the conclusion of a scientific research study to support the interests of the study's financial sponsor. This phenomenon is recognized sufficiently that researchers undertake studies to examine bias in past published studies. Funding bias is an instance of experimenter's bias
.
as a trait in which a person feels obliged to return favors. This trait is embodied in all human cultures. Human nature may influence even the most ethical researchers to be affected by their sponsors, although they may genuinely deny it.
, for example, would publish their own internal research that invariably found minimal adverse health effects of passive smoking
.
A company that hires researchers to perform a study may require the researchers to sign a nondisclosure agreement before they are funded, by which researchers waive their right to release any results independently and release them only to the sponsor. The sponsor may fund several studies at the same time, suppressing results found contrary to their business interests while publicizing the results that support their interests. Indeed, a review of pharmaceutical studies revealed that research funded by drug companies was less likely to be published, but the drug-company-funded research that was published was more likely to report outcomes favorable to the sponsor.
A double-blind study with only objective measures is less likely to be biased to support a given conclusion. However, the researchers or the sponsors still have opportunities to skew the results discarding or ignoring undesirable data, qualitatively characterizing the results, and ultimately deciding whether to publish at all. Also, not all studies are possible to conduct double-blind.
writes that funding bias may be a form of publication bias
. Because it is easier to publish positive results than inconclusive or no results, positive results may be correlated with being positive for the sponsor.
Outcome reporting bias
is related to publication bias and selection bias, in which multiple outcomes are measured but only the significant outcomes are reported, while insignificant or unfavorable outcomes are ignored.
may result in a non-representative population of test subjects in spite of best efforts to obtain a representative sample. Even a double-blind study may be subject to biased selection of dependent variables, population (via inclusion and exclusion criteria, sample size, statistical methods, or inappropriate comparators, any of which can bias the outcome of a study to favor a particular conclusion.
Experimenter's bias
In experimental science, experimenter's bias is subjective bias towards a result expected by the human experimenter. David Sackett, in a useful review of biases in clinical studies, states that biases can occur in any one of seven stages of research:...
.
Human nature
The psychology text Influence: Science and Practice describes the act of reciprocityReciprocity (social psychology)
Reciprocity in social psychology refers to responding to a positive action with another positive action, rewarding kind actions. People categorize an action as kind by viewing its consequences and also by the person's fundamental intentions. Even if the consequences are the same, underlying...
as a trait in which a person feels obliged to return favors. This trait is embodied in all human cultures. Human nature may influence even the most ethical researchers to be affected by their sponsors, although they may genuinely deny it.
Misconduct
Scientific malpractice involving shoddy research or data manipulation does occur in rare instances. Often, however, the quality of manufacturers' studies are at least as good as studies that were not funded by a special interest. Therefore, bias usually occurs for other reasons.Predetermined conclusion
Research results can be selected or discarded to support a predetermined conclusion. The tobacco industryTobacco industry
The tobacco industry comprises those persons and companies engaged in the growth, preparation for sale, shipment, advertisement, and distribution of tobacco and tobacco-related products. It is a global industry; tobacco can grow in any warm, moist environment, which means it can be farmed on all...
, for example, would publish their own internal research that invariably found minimal adverse health effects of passive smoking
Passive smoking
Passive smoking is the inhalation of smoke, called secondhand smoke or environmental tobacco smoke , from tobacco products used by others. It occurs when tobacco smoke permeates any environment, causing its inhalation by people within that environment. Exposure to secondhand tobacco smoke causes...
.
A company that hires researchers to perform a study may require the researchers to sign a nondisclosure agreement before they are funded, by which researchers waive their right to release any results independently and release them only to the sponsor. The sponsor may fund several studies at the same time, suppressing results found contrary to their business interests while publicizing the results that support their interests. Indeed, a review of pharmaceutical studies revealed that research funded by drug companies was less likely to be published, but the drug-company-funded research that was published was more likely to report outcomes favorable to the sponsor.
A double-blind study with only objective measures is less likely to be biased to support a given conclusion. However, the researchers or the sponsors still have opportunities to skew the results discarding or ignoring undesirable data, qualitatively characterizing the results, and ultimately deciding whether to publish at all. Also, not all studies are possible to conduct double-blind.
Publication bias
Scientist researcher Anders SandbergAnders Sandberg
Anders Sandberg is a researcher, science debater, futurist, transhumanist, and author. He was born in Solna, Sweden. He holds a Ph.D...
writes that funding bias may be a form of publication bias
Publication bias
Publication bias is the tendency of researchers, editors, and pharmaceutical companies to handle the reporting of experimental results that are positive differently from results that are negative or inconclusive, leading to bias in the overall published literature...
. Because it is easier to publish positive results than inconclusive or no results, positive results may be correlated with being positive for the sponsor.
Outcome reporting bias
Reporting bias
In empirical research, reporting bias refers to a tendency to under-report unexpected or undesirable experimental results, attributing the results to sampling or measurement error, while being more trusting of expected or desirable results, though these may be subject to the same sources of error...
is related to publication bias and selection bias, in which multiple outcomes are measured but only the significant outcomes are reported, while insignificant or unfavorable outcomes are ignored.
Selection of subjects or comparators
Selection biasSelection bias
Selection bias is a statistical bias in which there is an error in choosing the individuals or groups to take part in a scientific study. It is sometimes referred to as the selection effect. The term "selection bias" most often refers to the distortion of a statistical analysis, resulting from the...
may result in a non-representative population of test subjects in spite of best efforts to obtain a representative sample. Even a double-blind study may be subject to biased selection of dependent variables, population (via inclusion and exclusion criteria, sample size, statistical methods, or inappropriate comparators, any of which can bias the outcome of a study to favor a particular conclusion.
Examples
- A 1996 study on the effects of nicotineNicotineNicotine is an alkaloid found in the nightshade family of plants that constitutes approximately 0.6–3.0% of the dry weight of tobacco, with biosynthesis taking place in the roots and accumulation occurring in the leaves...
on cognitive performanceCognitive deficitCognitive deficit, also known as cognitive impairment is an inclusive term to describe any characteristic that acts as a barrier to cognitive performance...
revealed that findings of nicotine or smoking improving performance were more likely to be published by scientists who acknowledged tobacco industry support.
- A 2003 study of published research on antidepressants found that studies sponsored by manufacturers of selective serotonin reuptake inhibitorSelective serotonin reuptake inhibitorSelective serotonin re-uptake inhibitors or serotonin-specific reuptake inhibitor are a class of compounds typically used as antidepressants in the treatment of depression, anxiety disorders, and some personality disorders. The efficacy of SSRIs is disputed...
s (SSRI) and newer antidepressents tended to favor their products over alternatives when compared to non-industry-funded studies. Also, modelling studies funded by industry were more favorable to industry than studies funded by non-industry sponsors. In general, studies funded by drug companies are four times more likely to favor the drug under trial than studies funded by other sponsors.
- A 2006 review of experimental studies examining the health effects of cell phone useMobile phone radiation and healthThe effect of mobile phone radiation on human health is the subject of recent interest and study, as a result of the enormous increase in mobile phone usage throughout the world . Mobile phones use electromagnetic radiation in the microwave range...
found that studies funded exclusively by industry were least likely to report a statistically significant result.
- The US Food and Drug AdministrationFood and Drug AdministrationThe Food and Drug Administration is an agency of the United States Department of Health and Human Services, one of the United States federal executive departments...
(FDA) determined in 2008 that the bisphenol A (BPA) in plastic containers is safe when leeched into food, citing chemical industry studies. Independent research studies reached different conclusions, with over 90 percent of them finding health effects from low doses of BPA.
- Two opposing commercial sponsors can be at odds with the published findings of research they sponsor. A 2008 Duke University study on rats, funded by the Sugar Association, found adverse effects of consuming the artificial sweetener SplendaSplendaSplenda is the commercial name and registered trade mark of a sucralose-based artificial sweetener derived from sugar, owned by the British company Tate & Lyle. Sucralose was discovered by Tate & Lyle and researchers at Queen Elizabeth College, University of London, in 1976...
. The manufacturer, Johnson & JohnsonJohnson & JohnsonJohnson & Johnson is an American multinational pharmaceutical, medical devices and consumer packaged goods manufacturer founded in 1886. Its common stock is a component of the Dow Jones Industrial Average and the company is listed among the Fortune 500....
subsidiary McNeil Nutritionals LLC, responded by sponsoring its own team of experts to refute the study.