Reducing population stratification bias: stratum matching is better than exposure.

@article{citeulike:3043976, abstract = {OBJECTIVE: Genetic studies of complex human diseases rely heavily on the epidemiologic association paradigm, particularly the population-based case-control designs. This study aims to compare the matching effectiveness in terms of bias reduction between exposure matching and stratum matching. STUDY DESIGN AND SETTING: Formulas for population stratification bias were derived. An index of matching effectiveness was constructed to compare the two types of matching. RESULTS: It was found that exposure matching can paradoxically increase the magnitude of population stratification bias sometimes, whereas stratum matching can guarantee to reduce it. CONCLUSION: The authors propose two simple rules for genetic association studies: (a) to match on anything that helps to delineate population strata such as race, ethnicity, nationality, ancestry, and birthplace and (b) to match on an exposure only when it is a strong predictor of the disease and is expected to have great variation in prevalence across population strata.}, address = {Research Center for Genes, Environment and Human Health, College of Public Health, National Taiwan University, Taiwan; Graduate Institute of Epidemiology, College of Public Health, National Taiwan University, Taiwan.}, author = {Lee, Wen-Chung C. and Wang, Liang-Yi Y. }, citeulike-article-id = {3043976}, doi = {10.1016/j.jclinepi.2008.02.016}, issn = {0895-4356}, journal = {Journal of clinical epidemiology}, keywords = {stratification}, month = {July}, posted-at = {2008-07-26 02:06:07}, priority = {2}, title = {Reducing population stratification bias: stratum matching is better than exposure.}, url = {http://dx.doi.org/10.1016/j.jclinepi.2008.02.016}, year = {2008} }

TY - JOUR ID - citeulike:3043976 L3 - citeulike-article-id:3043976 TI - Reducing population stratification bias: stratum matching is better than exposure. JF - Journal of clinical epidemiology AD - Research Center for Genes, Environment and Human Health, College of Public Health, National Taiwan University, Taiwan; Graduate Institute of Epidemiology, College of Public Health, National Taiwan University, Taiwan. SN - 0895-4356 N2 - OBJECTIVE: Genetic studies of complex human diseases rely heavily on the epidemiologic association paradigm, particularly the population-based case-control designs. This study aims to compare the matching effectiveness in terms of bias reduction between exposure matching and stratum matching. STUDY DESIGN AND SETTING: Formulas for population stratification bias were derived. An index of matching effectiveness was constructed to compare the two types of matching. RESULTS: It was found that exposure matching can paradoxically increase the magnitude of population stratification bias sometimes, whereas stratum matching can guarantee to reduce it. CONCLUSION: The authors propose two simple rules for genetic association studies: (a) to match on anything that helps to delineate population strata such as race, ethnicity, nationality, ancestry, and birthplace and (b) to match on an exposure only when it is a strong predictor of the disease and is expected to have great variation in prevalence across population strata. KW - stratification AU - Lee, Wen-Chung AU - Wang, Liang-Yi PY - 2008/07/09/ UR - http://dx.doi.org/10.1016/j.jclinepi.2008.02.016 ER -