Pamela J. Mink|Michael Goodman|Leila M. Barraj|Harriet H. Imrey|Michael A. Kelsh|Janice W. Yager
Evaluation of Uncontrolled Confounding in Studies of Environmental Exposures and Neurobehavioral Testing in Children
Exponent (United States)
neurobehavioral tests commonly used studies children exposed lowlevel environmental concentrations compounds known neurotoxic higher levels however uncontrolled incomplete control confounding makes interpretation results problematic effects confounders often stronger effects primary interest examined priori potential impact confounding hypothetical study evaluating association potentially neurotoxic environmental exposure neurobehavioral function childrenwe used 2 outcome measures bayley scales infant development mental development index stanfordbinet intelligence scale composite score selected 3 potential confounders maternal intelligence home environment socioeconomic status measured years parental education conducted 3 sets analyses measuring effect 3 confounding factors alone 2 confounders acting simultaneously 3 confounders acting simultaneouslyrelatively small differences 05 standard deviations confounding variables exposed unexposed groups unmeasured unaccounted analysis could produce spurious differences cognitive test scores magnitude difference 310 points suggested meaningful impact populations method measuring confounders eg maternal intelligence could also substantially affect resultsit important carefully consider impact potential confounders planning stages observational study studytostudy differences neurobehavioral outcomes similar environmental exposures could partially explained differences adjustment confounding variables