Effect of marital status on death rates. Part 1: High accuracy exploration of the Farr-Bertillon effect

TL;DR

This study rigorously analyzes the Farr-Bertillon law, confirming that married individuals generally have lower death rates than unmarried ones, with variations across age, gender, and cause of death, using highly accurate data analysis methods.

Contribution

It provides the most precise validation of the Farr-Bertillon effect across different demographics and causes of death, addressing previous data limitations.

Findings

The Farr-Bertillon effect is similar for men and women, stronger for men.

Largest effect for singles/divorced around age 45, widowed around age 25.

Highest effect observed for suicide, lowest for cancer.

Abstract

The Farr-Bertillon law says that for all age-groups the death rate of married people is lower than the death rate of people who are not married (i.e. single, widowed or divorced). Although this law has been known for over 150 years, it has never been established with great accuracy. This even let some authors argue that it was a statistical artefact. It is true that the data must be selected and analyzed with great care, especially for age groups of small size such as widowers under 25. The observations reported in this paper were selected and designed in the same way as experiments in physics, that is to say with the objective of minimizing the error bars for all age-groups. It will be seen that data appropriate for mid-age groups may be unsuitable for young age groups and vice versa. The investigation led to the following results. (1) The FB effect is basically the same for men and women, except that on average it is about 20\% stronger for men. (2) There is a marked difference between single or divorced persons on the one hand, for whom the effect is largest around the age of 45, and widowed persons on the other hand, for whom the effect is largest around the age of 25. (3) When different causes of death are distinguished, the effect is largest for suicide and smallest for cancer. (4) For young widowers the death rates are up to 10 times higher than for married persons of same age. This extreme form of the FB effect will be referred to as the "young widower effect." A possible connection between the FB effect and Martin Raff's "Stay alive" effect for cells in an organism is discussed in the last section.