A New York Times article called "A Big Professional Headache" reports that "neurologists suffer many more migraines than the general population, [. . .] and for those neurologists who specialize in treating headaches, the incidence is even higher [. . .] Eighteen percent of women and 6% of men in the general population say they have at least one migraine in a given year. Among women practicing neurology, the figure was 58%, and among the men, 34%. The difference was even more pronounced for headache specialists. Seventy-four percent of the women reported having migraines, as did 59% of the men."7
a. Was this an experiment or an observational study?
b. If we are only interested in whether or not a person suffers from migraines, then we are considering a single categorical variable. The study described above actually features two additional variables. Tell what they are and if they are quantitative or categorical.
c. Does this pair of pie charts depict percentages for men and women in the general population, among neurologists, or among headache specialists?
d. Report results for female and male neurologists, using the word "risk."
e. Report results for female and male neurologists, using the words "majority" and "minority."
f. The researchers who reported these results wrote that, "perhaps the prevalence of migraine in the general population is greater than studies would suggest, and neurologists are either better able to self-diagnose or better able to remember headaches with specific features." Is this suggesting bias in the assessment of the variable's values, or is it providing an explanation for why neurologists may actually be different from the rest of the population with respect to suffering from migraines?
g. An alternative explanation, according to the article, is that "doctors with histories of migraines are drawn to study them, or that the kind of people who become neurologists are the kind of people who get migraines." Is this suggesting bias in the assessment of the variable's values, or is it providing an explanation for why neurologists may actually be different from the rest of the population with respect to migraines?