TY - JOUR
T1 - Estimating familial aggregation while adjusting for covariates Application to pulmonary function data from black and white sibships
AU - Cotch, Mary Frances
AU - Beaty, Terri H.
AU - Muñoz, Alvaro
AU - Cohen, Bernice H.
N1 - Funding Information:
This research was supported by National Heart, Lung, and Blood Institute grant ROl-HL28872.
PY - 1992/5
Y1 - 1992/5
N2 - Although crude correlations are useful in family studies, some adjustment for effects of risk factors that vary both within and among families if often needed. A linear model for estimating sibship correlations while simultaneously considering height, age, race, sex, ascertainment, and smoking status was used on pulmonary function data on 1-second forced expiratory volume (FEV1) and the natural logarithm of the ratio of FEV1 to forced vital capacity (lnFEV%) from 402 adults in 152 white sibships and 172 adults in 59 black sibships. Crude correlations of .271 ± .048 (FEV1) and .342 ± .047 (lnFEV%) decreased significantly to .206 ±. 048 and .231 ± .048, respectively, after adjustment. For black and white sibs, adjusted intraclass correlations, although not statistically different, were .153 ± .089 and .225 ± .055 (FEV1), respectively, and were .103 ± .088 and .275 ± .054 (lnFEV%), respectively, suggesting that pulmonary function may aggregate more strongly among whites. This analysis illustrates how risk factor adjustment can be readily incorporated into familial correlation studies.
AB - Although crude correlations are useful in family studies, some adjustment for effects of risk factors that vary both within and among families if often needed. A linear model for estimating sibship correlations while simultaneously considering height, age, race, sex, ascertainment, and smoking status was used on pulmonary function data on 1-second forced expiratory volume (FEV1) and the natural logarithm of the ratio of FEV1 to forced vital capacity (lnFEV%) from 402 adults in 152 white sibships and 172 adults in 59 black sibships. Crude correlations of .271 ± .048 (FEV1) and .342 ± .047 (lnFEV%) decreased significantly to .206 ±. 048 and .231 ± .048, respectively, after adjustment. For black and white sibs, adjusted intraclass correlations, although not statistically different, were .153 ± .089 and .225 ± .055 (FEV1), respectively, and were .103 ± .088 and .275 ± .054 (lnFEV%), respectively, suggesting that pulmonary function may aggregate more strongly among whites. This analysis illustrates how risk factor adjustment can be readily incorporated into familial correlation studies.
KW - Epidemiologic methods
KW - ethnic groups
KW - family correlations
KW - spirometry
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U2 - 10.1016/1047-2797(92)90064-W
DO - 10.1016/1047-2797(92)90064-W
M3 - Article
C2 - 1342282
AN - SCOPUS:0026743991
SN - 1047-2797
VL - 2
SP - 317
EP - 324
JO - Annals of Epidemiology
JF - Annals of Epidemiology
IS - 3
ER -