Title: Selective migration as a bias in modernization studies: premigration differences in morphology and blood pressure among 15-30 year-old American Samoans.

POPLINE Document Number: 208295

Author(s):

Pearson JD
Hanna JM

Source citation:

American Journal of Human Biology, 1989;1(3):263-9.

Abstract:

Pre-migration differences in anthropometry and blood pressure are examined for evidence of selective migration for biological characteristics. The authors conducted a 5-year follow-up of the migration status of 99 American Samoans 15-30 years old who had been previously examined in 1981 and found that 33 had migrated. Analysis of covariance of the baseline anthropometry and blood pressures of the nonmigrants (n=58) and those who subsequently migrated (n=29) indicates that selective migration does occur among young American Samoan adults. Migrants of both sexes tend to be younger and leaner and have significantly lower mean blood pressures than nonmigrants even before migration. Selective migration of lean individuals with lower blood pressures may contribute to the lower blood pressures of migrants from American Samoa living in Hawaii or to the heterogeneity in other Samoan populations. These results are 1 of the few examples of biological selectivity demonstrated to date and illustrate the dangers of assuming that the effects of selective migration are negligible in studies of migration and health. (author's)

Keywords:

Hawaii
Samoa
International Migration
Migrants
Bias
Blood Pressure
Anthropometry
Age Factors
Nonmigrants
Sex Factors
Biological Characteristics
United States
Developed Countries
North America
Americas
Developing Countries
Oceania
Migration
Population Dynamics
Demographic Factors
Population
Error Sources
Measurement
Research Methodology
Hemic System
Physiology
Biology
Population Characteristics