Table 1. The effect of year of birth, fitted with a polynomial regression, and the geographical and genetic (maternal/paternal) origin on the lifespan of carriers.

	DF	MS	F	P
Birth Year (3)	3	6622.2	43.705	2.2*10–16
Geographical origin	1	1563.3	10.317	0.0016
Genetic origin	1	1242.1	8.197	0.0048
Residuals	145	151.5

DF, MS, and F signify degrees of freedom, mean square and F-statistic, respectively.