DEXAMETHASONE THERAPY AND IQ
On page 439, we presented cognition data obtained by researchers studying the effects of early postnatal dexamethasone therapy for the prevention or treatment of chronic lung disease of prematurity. The study included 146 school-age children of which 72 had been in a dexamethasone group and 74 had been in a control group. As infants, all of the children in both groups had severe respiratory distress syndrome (RDS) due to insufficiently developed lungs.
To measure cognition, the researchers employed the Wechsler Intelligence Scale for Children. Third Edition (WISC-III). Use the data in the table to perform the following statistical inferences for each of the three WISC-III main scales and each of the four WISC-III subscales. So, you will need do parts (a)and(b) seven times.
- a. At the 5% significance level, do the data provide sufficient evidence to conclude that a difference exists between
mean scores of school-age children who as (premature) infants receive dexamethasone therapy and those who do not? - b. Determine and interpret a 95% confidence interval for the difference between mean scores of school-age children who as (premature) infants do not receive dexamethasone therapy and those who do.
- c. Discuss your results in detail.
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Introductory Statistics (10th Edition)
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