Nestled in the stacks of a Yale University library rests more than two decades' worth of data from a contentious study examining the likes and differences of twins and triplets reared separately as part of a state-sanctioned experiment.
In the 1960s, clinical psychiatrist Peter Neubauer and a New York adoption agency arranged to place several twin pairs and one set of triplets in different homes in order to prospectively study their lives, as the . The study, which has since been -- for example, neither the children's biological parents nor the adopting families were informed -- was an attempt to get at the central psychological questions of "nature versus nurture" and the "twinning reaction."
Neubauer, who died in 2008, never published a comprehensive account of the study's findings, although some made their way into a 1996 book he wrote with his son Alexander, titled .
In 2018, the study became the subject of two documentaries: which details the story of the study's triplet brothers who coincidentally met on their shared college campus, and which tells a pair of twins' similar story.
Central to the documentaries' themes is the air of secrecy surrounding Neubauer's experiment that has inspired some healthcare professionals to demand the research files be released, despite Yale's commitment to keep them sealed until 2065. But according to Leon Hoffman, MD, and Lois Oppenheim, PhD, of the New York Psychoanalytic Society and Institute, writing in a commentary, the "focus on the human costs of the study obscures important historical and scientific misunderstanding that deserve clarification."
spoke with Hoffman about aspects of the study the filmmakers may have gotten wrong and the study's implications for clinical research today. Below is a transcript of his remarks, which have been edited for brevity and clarity.
What should we keep in mind when interpreting the study and these documentaries?
Hoffman: I think one thing is that the idea of secrecy was not done maliciously. The idea of open adoption was way, way in the future. The rule was, you were not allowed to tell the adoptive parents anything about the biological parents. The other thing is that this was early in terms of informed consent. It was just being developed over that time. There were also no [institutional review boards] at the time.
From a contemporary perspective, I think the important thing to learn -- even with all these safeguards that we have now -- is you always have to think about unintended consequences. I think, to me, that's the most important lesson from this. [Neubauer] was really trying to keep the confidentiality of the kids, of the family.
Then the other important thing is in terms of psychoanalytic theory, particularly then, the idea of separation, individualization was very important. The question of the "twinning reaction." There are a lot of articles about this, that twins could either become so opposite to one another or be so identical that their own personalities fuse and merge. The other thing was that there was this data that twins were more difficult for the mother and that it would be easier for the mother to take care of one child instead of two children.
What ideas are brought up in the story that are still relevant today? Why is there this resurfacing of these stories now, some 60 years later?
Hoffman: I think the problem with this and probably a lot of other "exposés" is that we judge the past by our present values. In one of the articles [I wrote] about this study, I think I quote this article by [Samuel] Abrams and his introductory paragraph says there was thought that twins would be better off separated if they're going to be adopted.
I think the main trouble I had with the film was that the real distortion was that it was done in order to experiment on them rather than this was an experiment in nature which then was studied. Back in that time, there were a lot of these discussions about genes versus environment.
I always tell parents of kids that I see, "How much is genetic and how much is environment?" and I always say, "It's 100% of both," because those two are always interacting with one another. More and more data has shown that genetic variations get very much affected by the environment.
Do you think Neubauer was right to seal the study forms? Why or why not?
Hoffman: What would I have done 20 years ago? I really have no idea. Neubauer was very much concerned with confidentiality. That's why they never really published the details because it would be too revealing. Was he right to seal it? I don't know. That's always a question. The triplets, the two surviving triplets and the twins in the other movie, they got access to their papers. He probably thought that would be the safest thing to do, I would say. Whether he's right or wrong, I don't know. We always have 20/20 hindsight, but that I don't know.
What lessons can we bring forward from this study and this story in regards to medical ethics today? How do you think it has shaped clinical research today?
Hoffman: I think it really shows the importance of informed consent, number one. Number two, it also shows us that even when you do get informed consent, you just don't know what's going to happen. It's really hard to predict the future of what would be the consequences of what you do. But the importance of informed consent is really probably the central issue.
What is the most interesting part or most important takeaway in this story?
Hoffman: The filmmaker had an opportunity to explore the whole issue of what is it like to study human activity in a naturalistic way and how difficult it is to study. That kind of study is very different than a more rigorous, controlled trial where a procedure will be implemented with one group and not with another group. Naturalistic studies are very, very hard to do because you have so many variables. Retrospectively, let's say, if that were being done now, people would give you permission to study your family or to study a group of families. That's the way it's done now. How one does "clinical research," you have to think about what the impact might be if the person's identity is revealed inadvertently.
Disclosures
Hoffman did not report any disclosures.
Primary Source
JAMA
Hoffman L, Oppenheim L "Three Identical Strangers and The Twinning Reaction -- clarifying history and lessons for today from Peter Neubauer's twins study" JAMA 2019; 322(1)10-12.