Blood lead levels exceeding 10 micrograms per deciliter have been shown to be harmful to mental and physical development in children. The U.S. Centers for Disease Control and Prevention in Atlanta estimated that about 500,000 children in the U.S. have blood concentrations of lead higher than this level.

judgement sample? simple random sample? convenience sample? systematic sample? (select all that apply)

Question

Blood lead levels exceeding 10 micrograms per deciliter have been shown to be harmful to mental and physical development in children. The U.S. Centers for Disease Control and Prevention in Atlanta estimated that about 500,000 children in the U.S. have blood concentrations of lead higher than this level.
 
judgement sample? simple random sample? convenience sample? systematic sample? (select all that apply)

anonymous · Answer

I think you need more information, unless you know for certain that the U.S. Centers for Disease Control and Prevention in Atlanta always use a particular type of sample. The two best options are systematic sample or simple random sample. The CDC would rarely rely on a convenience sample. I have no idea what a judgment sample is (probably a distraction). The CDC has a tendency to take samples that are representative of the general population; therefore, they would take a simple random sample, or a stratified random sample. A stratified random sample might be described by some as a "systematic" sample, as the number of people sampled from each strata (or grouping) would be predetermined and systematic.