1.You have access to pediatricians' records from a small practice in the Bronx for the last 10 years. They collect anonymous data on their patients every six months. Some of the data they collect are body measurements, immunizations records, instances of illness/injuries, and demographic characteristics. There are 150 boys and 140 girls in the practice.

a.What kind of study is this? _____________________

(Clinical Trial, Prospective Cohort, Cross Sectional or Case- Control Study)

b.You have data on kids' sex and their instances of injuries in the last year. 35 boys and 20 girls have been injured at home. 15 boys and 12 girls have reports of injuries in school. 10 boys and 15 girls have reports of injuries in other places. Construct a 3 x 2 table of injuries in boys and girls. Hint: not all kids have injuries.

c.What kind of variable is injuries in this study? ___________________

(Ordinal or Nominal)

d.What is the prevalence of injuries at home in this sample? Hint: consider the total of the sample, including the kids who are not injured.

e.Construct a frequency and relative frequency table for the injury types of boys. Assume that each child can only be injured once (or not at all).

f.What is the probability that a girl will have an injury outside of the home?

g. You also found that the entire sample of kids has a mean BMI of 22.5, with a standard deviation of 6.75. Calculate a 95% confidence interval for BMI and interpret.