Question

To determine the proportion of cesarean sections among obstetrical deliveries in Baltimore, a random sample of histories was obtained from two obstetrical services: Johns Hopkins Hospital and University Hospital. The rate of cesarean sections for the sample was 20%. Later more complete information revealed that it was not indicative of the general experience throughout the city. Most hospitals in the city were found to have rates ranging from 10% to 12%.

a) What is the target population for this study?

b) What is the parameter of interest?

c) What was the sampling frame used?

d) What main variable of interest was collected on each subject? Is this variable categorical or numeric?

e) Would you regard the estimate of the parameter of interest as biased even though a random selection of histories was obtained? Why or why not?

Answer 1

a) All obstetric deliveries in Baltimore

b) the proportion of cesarean sections among obstetrical deliveries in Baltimore.

c) All obstetric deliveries in Johns Hopkins Hospital and University Hospital.

d) The main variable of interest was cesarean sections among obstetrical deliveries. Ans this variable is categorical, because either there is cesarean section or not. we have only two choices.

e) The sample was conducted for only two hospitals in the city, used in the study. and therefore would be expected the biasedness.

answered by: anonymous