We’re almost finished with our broad tour of how scientific research proceeds. However, one last issue demands comment. It’s not about how research is carried out or how find-ings are interpreted. Instead, it’s about what research can and cannot be done.
As we’ve seen, the external validity of an investigation depends on the relationship between a study and its real-world context. This, in turn, requires us to study real peo-ple and real animals. And this requirement brings with it a demand that psychological research be conducted ethically, using methods that protect the rights and well-being of the research participants.
Psychologists are serious about research ethics. Virtually every institution sponsor-ing research—every college and university, every funding agency—has special committees charged with the task of reviewing research proposals to make sure the procedures adequately protect human and animal participants. Researchers who study laboratory animals must protect the animals’ health and provide adequate housing and nutrition. In the United States, psychological research with human participants must also follow the guidelines established by the American Psychological Association (1981, 1982), one of psychology’s most prominent professional organizations. The U.S. government also has regulations governing research with human participants. Institutions failing to observe these regulations are ineligible to receive grants from federal agencies, such as the National Science Foundation or the National Institutes of Health. Similar guidelines to protect research participants are in place in many other countries; for example, the Council for International Organizations of Medical Sciences published a set of international guidelines for research ethics in 2002. And, independent of international boundaries, most psychological research journals require that when publishing research, authors clearly state that their study observed all the rules protecting the participants.
Human participants must not only be protected physically; we must also respect their privacy, autonomy, and dignity. Accordingly, an investigator must guarantee that the data are collected either anonymously or confidentially and that participants are not treated in any way they might find objectionable. Before the study begins, the inves-tigator must give participants as much information as possible about what their task will involve, inform them of any risks, and assure them they can leave the study at any time. Based on that information, the participants can decide for themselves whether they’ll continue in the study—and so the procedure is run and the data collected only after participants have given their informed consent.
Then, at the end of the experiment, the investigator must debrief the participants— that is, explain to them what the experiment involved and why. If the experiment involved any deception or hidden manipulation, this must be revealed. If the study involved any manipulation of beliefs, mood, or emotion, the investigator must attempt to undo these effects. Ideally, participants should leave the study with some under-standing of how the research, and their participation in it, may benefit psychological knowledge and human welfare.
Be aware that these ethical protections—especially the need to obtain informed consent—can conflict with the procedures needed to ensure the study ’s validity. In some cases, for example, the validity of a study requires keeping research partici-pants somewhat uninformed about the study ’s design. Participants in a control group usually aren’t told they ’re in a control group, because hearing this might erode their motivation to perform well on the experimenters’ tasks. In the same way, subliminal self-help recordings are alleged to work through unconscious mechanisms. Thus, it may be important to keep the person who will hear the record-ing from knowing in advance exactly what message will be (subliminally) contained within the recording.
How can investigators resolve these conflicts between ensuring experimental validity and continuing to honor ethical standards? Overall, the ethical considerations must be the greater priority. Investigators must do everything they can to minimize the use of deception and guard against risks to research participants. If any risk remains, the inves-tigators must clearly and persuasively argue that the information to be gained from the experiment truly justifies the risk. Similarly, if an experiment involves deception, the investigators must explain how the scientific value of the experiment justifies that level of deception.
These decisions about risk or deception are sometimes difficult; indeed, the history of psychology includes many conflicts over the ethical acceptability of psychological studies (e.g., Baumrind, 1964; Hermann & Yoder, 1998; Korn, 1997; Milgram & Murray, 1992; Savin, 1973; Zimbardo, 1973). This is one reason that decisions about ethical acceptability usually aren’t made by the investigators themselves, but by a multidisciplinary supervisory committee—usually called an institutional review board, or IRB—assigned the task of protecting research participants.
Moreover, the requirement to protect human and animal rights simply prohibits some studies—no matter how much we might learn from them. For example, how does child abuse affect a child’s later social or emotional development? This deeply important question cannot be studied experimentally, because no researcher would physically abuse participants to study the outcomes. If we want to learn more about the effects of abuse, we need to find other means (such as a quasi-experimental design, in which the researcher evaluates children who—sadly—have already been abused).