title: [2 methods for the study of differential mortality based on sex: rates ratio and orthogonal regression].
abstract: Sex mortality differential is studied for all the causes of death, in La Coruña (Galicia, Spain), according to geographic area, zone (urban, semiurban and countryside) and decade (1961-1970 y 1971-1980). Two study methods are compared: a) Rate ratio (with direct age-adjusted rates); and b): Differential (Dj) between observed rate (M) and expected rate (M), for male mortality, according to female level (orthogonal regression model). t-Student-Fisher tests have been used to compare an observed mean and a theoretic one, and to compare two observed means, with independent data. An increase in male overmortality is found, from one to the other decade (112.9% to 117.0%), confirmed by orthogonal method: respectively 5.38 deaths every 100,000 and 16.81 deaths. This over-mortality is more frequent in the urban areas, while inframortality appears mainly in countryside areas. Furthermore, male overmortality increases in urban zones and decreases in semiurban and rural zones.
authors.forename: J M
authors.initials: JM
authors.lastname: Barros-Dios
authors.forename: M A
authors.initials: MA
authors.lastname: Juiz Crespo
mesh_terms: D000293:Adolescent; D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009026:Mortality; D012044:Regression Analysis; D012424:Rural Population / Q000706:statistics & numerical data; D012737:Sex Factors; D013030:Spain; D014505:Urban Population / Q000706:statistics & numerical data
vernacular_title: Dos métodos de estudio de la mortalidad diferencial según sexo: la razón de tasas y la regresión ortogonal.