Glossary.

Clinical and research terms

Monozygotic twins

Twins from a single fertilized egg that has split, producing two embryos with identical genetic material. The technical name for “identical twins.” The Neubauer study’s subjects were monozygotic twins and at least one set of monozygotic triplets. The genetic identity is what made the comparative design appealing to the researchers; it is also what makes the separation, retrospectively, particularly distressing to the subjects, who found upon reuniting that they had been deprived of a sibling who shared their biology entirely.

Twin study

A research design that uses twins as a way to separate genetic from environmental influences on a measured trait. Most twin studies are observational and use existing twin pairs — together-reared, separately-reared by circumstance, or in registries of identifiable populations. The Neubauer study was unusual in that the separation was not preexisting but engineered: subjects were placed apart specifically so that the comparison could be conducted.

Longitudinal study

A study that follows the same subjects over a long period, typically through repeated assessment at intervals. The Neubauer program was longitudinal: subjects were observed from infancy through later childhood, with periodic home visits and assessments throughout that span.

Informed consent

The principle that a research subject — or, where the subject cannot consent for themselves, the subject’s legal guardian — must understand what is being studied, what will be done, what risks attend participation, and that they may refuse. Informed consent is the foundational requirement of modern human-subjects research. None of the Neubauer subjects’ adoptive families gave it; none of the subjects, who were children, could.

Ethics and regulation

Institutional Review Board (IRB)

A committee at a research institution charged with reviewing proposed research involving human subjects to ensure it complies with ethical standards. The IRB system in its present form was established under the National Research Act of 1974 and elaborated in subsequent regulation. The Neubauer program predates the IRB system. A study of its design submitted to a contemporary IRB at any university or research hospital would not be approved.

The Belmont Report

The 1979 report of the National Commission for the Protection of Human Subjects of Biomedical and Behavioral Research, which set out three foundational principles for the ethics of research involving human subjects: respect for persons, beneficence, and justice. The report has structured American research-ethics regulation since. By all three standards, the Neubauer study fails.

Separate placement

The adoption-practice term for placing siblings — including twins and triplets — in different adoptive homes rather than together. Louise Wise Services practiced separate placement for identical multiples as a matter of policy from at least the early 1960s, on the advice of Viola Bernard. Most adoption agencies in subsequent decades moved toward sibling-together placement as the default, on grounds that have substantial empirical support.

Archival terms

Deed of gift

A legal instrument by which a donor transfers ownership of a collection of materials — papers, books, films, recordings — to an institution that will preserve and steward it. Deeds of gift typically specify access conditions: who may use the material, under what supervision, and from what date forward. The Neubauer collection at Yale is governed by a deed of gift whose terms restrict access until 2065. Those terms can be amended by the parties to the deed (or their successors).

Finding aid

A descriptive document, usually published online by an archival repository, that lists the contents of a collection at a level of detail (typically box and folder) that allows researchers to know what is in the collection and request specific items. A finding aid does not release the contents of a collection; it makes the contents’ existence known. Whether Yale has produced a publicly accessible finding aid for the Neubauer collection is, as of this archive’s writing, not clear from the public record.

Redaction

The removal or obscuring of specific information in a document before release, typically to protect the identity of third parties or to comply with privacy requirements. The partial record releases that have occurred since 2018 are redacted releases. Redaction is the standard archival tool for releasing sensitive material and is, in this archive’s view, the appropriate mechanism for handling whatever third-party privacy concerns the Yale collection raises.

Institutions

Child Development Center

The Manhattan-based research and clinical institution, an arm of the Jewish Board of Guardians, where the Neubauer twin study was conducted. Full entry →

Louise Wise Services

The Jewish adoption agency in New York that placed the study’s subjects, separated identical siblings as a matter of policy, and closed in 2004. Adoption records are now held by Spence-Chapin Services to Families and Children. Full entry →

Jewish Board of Family and Children’s Services

The successor organization to the Jewish Board of Guardians, parent of the Child Development Center where the study was conducted. One of the institutions with standing to advocate for the opening of the Yale archive. Note: the Jewish Board does not hold the Louise Wise adoption records — those are at Spence-Chapin. Full entry →

Spence-Chapin Services to Families and Children

The New York adoption agency that has held the Louise Wise Services adoption records since the agency’s 2004 closure. The practical first stop for adoptees seeking confirmation of their adoption history, including any sibling information in the file. Full entry →

Yale University, Sterling Memorial Library, Manuscripts and Archives

The principal Yale library and the department within it that holds the Neubauer study’s research records. Custodian of the collection under the deed of gift; full entry →