Cross-sectional ecological design

Soil lead concentrations have been observed to be associated with children s blood lead concentrations using multiple study designs - cross-sectional, ecological spatial, ecological temporal, prospective soil removal and isotopic (Laidlaw Filippelli, 2008). 

One example of a nonexperimental study is the cohort study. A cohort study is a nonexperimental smdy that collects information from an identified group of individuals in an overall population, such as those receiving the marketed drug of interest (see Gamble 2014). Other smdy designs include case-control studies, cross-sectional studies, and ecological smdies. Case reports and case series can also be informative. 

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