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A randomized clinical trial compared aspirin to placebo for the prevention of heart attacks (MIs) and strokes. Out of a total of 1,000 subjects on aspirin, there were 80 heart attacks and 65 strokes; out of a total of 2,000 subjects on placebo, there were 240 heart attacks and 165 strokes. is there a significant […]

A survey was conducted where each participant was asked to choose their three favorite classical composers from the following list: The following data was recorded: Run the following program to create the SAS data set CLASSICAL. Using this data set as the starting point, write a SAS program to obtain a single frequency listing showing

A physical exam is given to a group of patients. Each patient is diagnosed as having none, one, two, or three problems from the following code list: The coding scheme is as follows: Using the sample data here: (a) Compute the mean HR, SBP, and DB? (b) Generate frequency counts for each of the nine

What’s wrong with this program?

Using data set CLINICAL from Problem 4.4, create a new SAS data set (CI-IANGE) with one observation per subject with the difference in WEIGHT between the first and last visit. Include in this data set the number of days between the first and last visit. Do not include any patients who have only one visit.

Write a program similar to Problem 4.5, except that we want to include all the data for each patient, excluding any patient who has had only one visit. Instead of having PROC MEANS create printed output, use it to create a SAS data set (PAT_MEAN) containing the mean for each patient (use the AUTO NAME

You want to randomly assign 48 subjects into two groups (Placebo and Drug). Write a DATA step to do this in such a way as to ensure there are exactly 24 subjects in each group. Can you think of how to do this so that in each group of eight subjects, there are exactly four

The same data as in problem 8.3 are to be analyzed. However, they are arranged so that the four ratings from each judge are on one tine. Thus, columns 1-3 are for the judge ID, column 4 is the rating for New York, column 5 for New Orleans, column 6 for Chicago, and column 7

Using the data set from problem 9.8, conduct a logistic regression predicting outcome (case or control) using SMOKING,ASBESTOS. and SES. Use a CLASS statement to create two dummy variables for SES, setting the reference level to ‘2-Mediurn’. (HINT: CLASS SES (PARAM=REF REF=’2-Medium’); PROC LOGISTIC uses the lower value formatted value of the outcome variable (if

Accident data, similar to Section G, are presented here. This time. we recorded accidents that occurred in the past year, based on the presence of a drinking problem and whether the driver had one or more accidents in the previous year. Run a forward stepwise logistic regression on these data, and write the resulting logistic