Epidemiology Ethics: Tuskegee, Supplements, and Study Design

The Tuskegee Syphilis Study: Ethical Violations in Biomedical Research

The U.S. Public Health Service Syphilis Study at Tuskegee, popularly referred to as the Tuskegee Syphilis Study, is infamous clinical research conducted in Macon County, Alabama, USA, from 1932 to 1972. The target population was Black men suffering from syphilis. The sample consisted of approximately six hundred uneducated Black men, of whom about four hundred had syphilis. The uninfected group of roughly two hundred men served as the control group. The study aimed to determine whether the reaction to syphilis among Black men was similar to that of white men and to establish how long a human being could live with untreated syphilis (Reverby, 2012). The following analysis evaluates the Tuskegee Syphilis Study to establish its ethical violations from a biomedical research perspective.

Based on the principles of ethical biomedical research involving human participants, it is clear that the Tuskegee Syphilis Study violated several fundamental requirements:

i. Lack of informed consent. There is no evidence that study participants were correctly informed of the study's purpose and their role in it, nor that they consented willingly to participate. Moreover, the study deliberately included uneducated Black men — suggesting a purposive sampling method — despite the existence of educated Black elites in the Tuskegee community at the time.

ii. Deception and non-beneficence. Although there was no known cure for syphilis at the time, the study was initially designed to make treatment available for African American men. This indicates that the researchers originally intended to carry out therapeutic measures, including providing a cure for or control of syphilis among participants. Study participants were also deliberately misinformed about the purpose of certain procedures; for example, spinal taps were disguised as a necessary and special "free treatment" for "bad blood."

iii. Withholding of vital information. At some point during the study, funding for drugs for participants was cut, at which point the study became a natural history study. Hundreds of participants infected with syphilis were kept in the dark about developments in the field and the progress of the research.

iv. Violation of non-maleficence. The researchers took no measures to avoid harming participants. On the contrary, active steps were taken to ensure harm:

v. Racism and inclusion of vulnerable groups. Although the targeted population was Black men, racism is evident in the deliberate selection of only uneducated Black men — a particularly vulnerable group given race relations in the United States at the time and the legacy of slavery. Furthermore, this vulnerable group received no benefit from their participation in the study.

vi. Endangering men and their families. At the time of the Tuskegee Syphilis Study, no treatment for syphilis existed. Moreover, ethical standards require that the dangers of any new medical intervention must first be investigated using animal subjects. It is therefore clear that the study participants were treated as human guinea pigs. The lack of treatment resulted in some women contracting the disease from participating men. Notably, no women were included in the study as participants.

vii. Annulment of the freedom to withdraw. In research involving human beings, participants must always retain the freedom to leave a study at any time. In this study, participants were closely monitored — including through the use of military personnel — to ensure that none withdrew. Even more troubling, participants were prevented from seeking medical care at nearby facilities.

viii. Abuse of study participants. The Tuskegee Syphilis Study was not unlike the Nazi-era medical experiments. It violated all the principles set forth in both the Declaration of Helsinki and the Nuremberg Code. The study harmed participants by maximizing risks and minimizing benefits. Human dignity was not respected, the privacy of participants was violated, and their autonomy was stripped away.

At the time the study was conducted, there was no established ethics code for biomedical research, and there was no requirement for research to be approved by an institutional review board — a body that would have detected the ethical issues and barred the study's implementation. Nevertheless, when the Judiciary Council of the American Medical Association issued a report on December 10, 1946, outlining ethics requirements for experiments involving human participants, the researchers of the Tuskegee Syphilis Study took no steps to revise or terminate the research (Ogungbure, 2011). The study continued until 1972 and was only terminated following public outcry.

PICO Analysis of the Vitamin and Mineral Supplements Systematic Review

The following section applies the PICO framework to the systematic review by Fortmann et al. (2013), titled "Vitamin and Mineral Supplements in the Primary Prevention of Cardiovascular Disease and Cancer: An Updated Systematic Evidence Review for the U.S. Preventive Services Task Force."

Population. The target population for this systematic review was research articles examining vitamin and mineral supplements. The review sought studies addressing the following nutrients: vitamins A, B1, B2, B6, B12, C, D, and E; calcium; zinc; iron; niacin; magnesium; β-carotene; folic acid; and selenium.

Intervention and Comparison. The intervention was the consumption of multivitamins or single and paired nutrient supplements. Studies included in this review examined participants who took such supplements. The comparison group consisted of community-dwelling, nutrient-sufficient adults who were not taking multivitamin supplements or single and paired nutrients.

Outcomes. The outcomes examined were the occurrence of cardiovascular disease (CVD), cancer, or all-cause mortality in an adult population without pre-existing CVD or cancer. The review compared health outcomes between community-dwelling, nutrient-sufficient adults who took supplements and those who did not.

Study Design. The inclusion criteria for this systematic review specified only studies that utilized a field experimental research design. While participants were observed in their natural community settings, supplement consumption served as the controlled variable, making this an experimental design. Accordingly, this systematic review is classified as using a field experimental research design.

Title and Abstract Screening. Two investigators independently reviewed each potential article's title and abstract and determined whether it met the pre-established inclusion criteria.

Risk of Bias Assessment. Two investigators independently assessed the quality of each included study and ranked it "good," "fair," or "poor" using predetermined quality criteria based on U.S. Preventive Services Task Force (USPSTF) methods.

Rationale for Multiple Reviewers. The purpose of using two or more reviewers to screen articles for inclusion in a systematic review is to: (1) improve the reliability, validity, and overall quality of the review; (2) minimize the risk of errors; (3) minimize the risk of selection bias, information bias, subjective opinion, and analytical bias; and (4) reduce meta-bias. Furthermore, under current requirements established by PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses), more than one reviewer must participate in the data extraction process.