Référence bibliographique 
Fox, Jonathan, Willführ, Kai, Gagnon, Alain, Dillon, Lisa et Voland, Eckart. 2017. «The Consequences of Sibling Formation on Survival and Reproductive Success Across Different Ecological Contexts: A Comparison of the Historical Krummhörn and Quebec Populations ». History of the Family, vol. 22, no 2/3, p. 364-423.
«This article investigates the relationship between the presence of additional siblings, in particular of the same gender, and the probabilities of survival, marriage, and reproductive success in the historical populations of the St Lawrence Valley in Quebec, Canada between 1670 and 1799 and of Krummhörn, Germany between 1720 and 1874.» (p. 365)
«Data for the historical population of Quebec come from the Registre de la population du Québec ancien (RPQA), created by the Programme de Recherche en Démographique Historique (PRDH) at the University of Montreal. The RPQA is a family reconstitution database with more than 700,000 linked Catholic baptisms, marriages, and burials registered in the Quebec parishes of the St Lawrence Valley from settlement in 1621 up to 1799, as well as death records from 1800 to 1850 of persons who died at age 50+ years.» (p. 371)
Type de traitement des données :
Analyse de contenu
Results show «that negative effects associated with sibling formation were strongest between same-sex siblings: having additional sisters was associated with poorer health and reproductive outcomes for girls than for boys, and having additional brothers was associated with poorer health and reproductive outcomes for boys than for girls. For some outcomes, additional siblings of the opposite sex even seemed to be beneficial. For example, additional brothers (sisters) were associated with decreased probability of death for infant girls (boys), and additional sisters were associated with an increase in the reproductive success of males in the Quebec region. [W]e also find notable differences across the two populations: beyond the higher mortality risks, higher proportion of persons married, and younger ages at marriage in Quebec, we observed some distinct sibship influences on those very outcomes. […] Furthermore, the presence of additional same-sex siblings in Quebec households did not seem to incur the same child mortality penalty that it did in the Krummhörn region, even though Quebec families in general experienced increasing levels of child mortality across the eighteenth century. […] Turning to our fertility outcome, the elevated negative impact of same-sex siblings in the Krummhörn region versus Quebec was only apparent in analyses which did not control for family-fixed effects. Results from these models indicate that additional brothers were significantly associated with higher numbers of births for both women and men in the Quebec region.» (p. 386-387).