PrepTest 53, Section 2, Question 8
Doctor: In three separate studies, researchers compared children who had slept with night-lights in their rooms as infants to children who had not. In the first study, the children who had slept with night-lights proved more likely to be nearsighted, but the later studies found no correlation between night-lights and nearsightedness. However, the children in the first study were younger than those in the later studies. This suggests that if night-lights cause nearsightedness, the effect disappears with age.
Doctor: In three separate studies, researchers compared children who had slept with night-lights in their rooms as infants to children who had not. In the first study, the children who had slept with night-lights proved more likely to be nearsighted, but the later studies found no correlation between night-lights and nearsightedness. However, the children in the first study were younger than those in the later studies. This suggests that if night-lights cause nearsightedness, the effect disappears with age.
Doctor: In three separate studies, researchers compared children who had slept with night-lights in their rooms as infants to children who had not. In the first study, the children who had slept with night-lights proved more likely to be nearsighted, but the later studies found no correlation between night-lights and nearsightedness. However, the children in the first study were younger than those in the later studies. This suggests that if night-lights cause nearsightedness, the effect disappears with age.
Doctor: In three separate studies, researchers compared children who had slept with night-lights in their rooms as infants to children who had not. In the first study, the children who had slept with night-lights proved more likely to be nearsighted, but the later studies found no correlation between night-lights and nearsightedness. However, the children in the first study were younger than those in the later studies. This suggests that if night-lights cause nearsightedness, the effect disappears with age.
Which one of the following, if true, would most weaken the doctor's argument?
A fourth study comparing infants who were currently sleeping with night-lights to infants who were not did not find any correlation between night-lights and nearsightedness.
On average, young children who are already very nearsighted are no more likely to sleep with night-lights than young children who are not already nearsighted.
In a study involving children who had not slept with night-lights as infants but had slept with night-lights when they were older, most of the children studied were not nearsighted.
The two studies in which no correlation was found did not examine enough children to provide significant support for any conclusion regarding a causal relationship between night-lights and nearsightedness.
In a fourth study involving 100 children who were older than those in any of the first three studies, several of the children who had slept with night-lights as infants were nearsighted.
0 Comments