It was discovered that a larger proportion of children who slept with nightlights later developed nearsightedness, compared to children who did not sleep with nightlights.The headlines read, "Leaving a light on for you children causes nearsightedness!" Later it was pointed out that nearsighted people have more trouble seeing in the dark and are more likely to leave lights on at night for their kids.And those same nearsighted parents are likely to have nearsighted kids.This is an example of ________________________ .
A)bias
B)a control group
C)a placebo
D)a randomized block design
E)a lurking variable

Question

Quizplus · Accepted Answer

This is an example of a lurking variable, where an unconsidered factor (the genetic predisposition to nearsightedness) influences the outcome of the study.

It Was Discovered That a Larger Proportion of Children Who