title: On the history of Hellin's law.
abstract: Theorems, proofs, laws and rules are commonly named according to the presumed investigator, but often earlier investigators have contributed substantially to the findings. One example of this is Hellin's law, which was named after Hellin, although he was not the first to discover it. In research on twinning and higher multiple maternities, the law has played a central role because it is approximately correct, despite showing discrepancies that are difficult to explain or eliminate. Several improvements to this law have been proposed. In this study, we re-examine some old papers to provide an overview of the scientists who have contributed to the genesis and the improvements of this law. In addition, we consider more recent contributions in which Hellin's law has been discussed and evaluated. It has been mathematically proven that Hellin's law does not hold as a general rule. However, most studies are based on empirical rates of multiple maternities, ignoring random errors. Such studies can never confirm the law, but only serve to identify errors too large to be characterized as random.
authors.affiliation: Folkhälsan Institute of Genetics, Department of Genetic Epidemiology, Helsinki, Finland. fellman@hanken.fi
authors.forename: Johan
authors.initials: J
authors.lastname: Fellman
authors.forename: Aldur W
authors.initials: AW
authors.lastname: Eriksson