Researchers must pay greater attention to the rights of study participants in pain research, concludes a recent paper by the Ethics Committee of the Pain-Omics Group.1

“Patients in pain, particularly chronic pain, are vulnerable by virtue of being in pain and in their desire to be relieved of pain,” says David B. Waisel, MD, senior associate in perioperative anesthesia at Children’s Hospital Boston and associate professor of anesthesia at Harvard Medical School. Waisel authored a recent review which found multiple, continuing ethical issues involving research on patients in pain.2

“A narrow path permits providing good clinical care, doing good research, and protecting patients from a desperate headlong rush into research that may prove deleterious to them,” says Waisel.

Widespread Ethical Issues

Some of the ethical issues Waisel found are widespread, but also are relevant to pain research. These include scientific misconduct, deception, placebo use, and genomics. Other ethical concerns are unique to pain research, such as research in neonatal pain management. “I approached this paper with the goal of including issues that were not commonly talked about,” says Waisel. Some unique ethical concerns in pain research include the following:

• Some studies inadequately manage pain in neonates. “Relatively minor procedures in the neonate, such as heel pricks, can have lifelong consequences,” says Waisel. “Too often, neonates do not receive pharmacologic or nonpharmacologic analgesia.”

While there are a number of validated analgesic therapies, most studies assessing pain management in neonates do not use these validated therapies in the control group. “This exposes the neonate to unnecessary harm and possible long-term consequences,” says Waisel.

This may be due to a misunderstanding that a new intervention must be compared to a placebo instead of to current therapies. “That is untrue, and, in fact, harmful to neonates,” says Waisel.

• Genetic pain research involving biobanking — the saving of a person’s tissue — raises privacy concerns. “This research is both incredibly valuable and very dangerous,” says Waisel.

There is a debate about how to ensure proper informed consent regarding privacy, known and unknown long-term harms, and use of the tissue for future undefined studies. “There are no set answers for these questions, but researchers may prioritize the sacred trust of holding individuals’ genomes,” says Waisel.

• Research fraud. A major scientific misconduct case involving multimodal pain therapy was discovered in 2009.3 Misconduct in pain research may lead to direct patient harm.

“Or there could be wider patient harm due to invalid data from inappropriate subject recruitment and data fabrication, falsification, or substandard research,” says Waisel.

As with all research with human subjects, pain research by responsible investigators must ensure that participants are fully informed of the goals, procedures, and risks of the study before giving their consent. However, there’s another important ethical consideration for participants who are in chronic, debilitating pain.

“Researchers have an added obligation that they are not providing consent in desperate situations,” says Robert Guerin, PhD, a bioethics fellow at Cleveland (OH) Clinic and an adjunct instructor in bioethics at Case Western Reserve University.

Potential participants may feel they have no choice but to enroll in the study in order to relieve terrible pain. “Such desperate situations lead to vulnerabilities to coercive enrollment in clinical trials,” says Guerin. He says pain researchers also have an ethical obligation to ensure that research subjects are not subject to stimuli that exceed a subject’s tolerance limit; that subjects should be able to escape or terminate a painful stimulus at will; and that minimal intensity of noxious stimuli necessary to achieve the goals of the study must be established and not exceeded.

“This should be discussed during the informed consent process,” says Guerin. “This ensures that patients are not subject to unnecessary harm during research.”

Trust between investigators and study participants is important in all research with human subjects. Its importance is perhaps more pronounced in pain research. “Participants must feel no pressure to misrepresent their pain for the sake of continuing a trial, or for the sake of discontinuing a trial,” says Guerin.


1. Compagnone C, Schatman ME, Rauck RL, et al. Past, present, and future of informed consent in pain and genomics research: Challenges facing global medical community. Pain Pract 2017; 17(1):8-15.

2. Waisel DB. Ethics of research for patients in pain. Curr Opin Anaesthesiol 2017; 30(2):205-210.

3. Rittner HL, Kranke P, Schafer M. What can we learn from the Scott Reuben case? Scientific misconduct in anaesthesiology. Anaesthesist 2009; 58(12):1199-1209.