Problem 1: The Medicare population is comprised of individuals with many health care needs, primarily because of their age. Cite barriers to obtaining measurements of health in this population and proposed methods for ensuring the quality of data collected.
Problem 2. A physical examination an audiometric test were given to 500 individuals with suspected hearing problems, of whom 300 were actually found to have hearing issues. The results of the examinations are presented in the following tables:
Physical examination results
Hearing problems 

Result 
Present 
Absent 
Positive 
240 
40 
Negative 
60 
160 
Audiometric Test results
Hearing problems 

Result 
Present 
Absent 
Positive 
270 
60 
Negative 
30 
140 
 Compute the sensitivity and specificity of the findings shown for the physical examination and audiometric test. What type of questions would specify and sensitive address?
 Compute the positive and negative predictive values of the findings shown for the physical examination and audiometric test. What type of questions would positive and negative predictive values address?
 Compared with the physical examination, how would you characterize the audiometric test in terms of its specificity and sensitivity?
 Compared with the physical examination, how would you characterize the audiometric test in terms of its positive and negative predictive values?
Problem 3. Two physicians were asked to classify 100 chest xrays as abnormal or normal independently. The comparison of their classification is shown in the following table:
Physician 2 
Total 

Physician 1 
Abnormal 
Normal 

Abnormal 
40 
20 
60 
Normal 
10 
30 
40 
Total 
50 
50 
100 
 Calculate the overall percent agreement between the two physicians.
 Would you characterize the value of kappa as poor, good or excellent?
Problem 4. Regression analysis in a research study
Using the following study entitled â€œCorrelates of recovery among older adults after major abdominal surgeryâ€ by Zalon, M.L. (2004) answer the following:
 What is the purpose of this study and how large is the sample size?
 Identify the dependent and independent variables.
 What statistical methods did the authors use to analyze the data and why?
 What was the percentage of variance explained by the regression analysis for functional status at 3 months?
 Discuss the multiple regression analysis results for functional status. What do these results indicate for practice?
Problem 5: Multiple Linear Regression
Suppose that a health researcher is interested in determining whether the distance between the patientâ€™s residence and source of care, and # of disability days significantly predict the number of visits at a local hospital.
Visits 
Distance 
Disability days 
7 
1 
8 
7 
1 
9 
2 
10 
1 
4 
4 
3 
5 
2 
5 
3 
9 
2 
2 
10 
1 
9 
2 
10 
6 
3 
7 
2 
11 
2 
4 
2 
3 
7 
2 
8 
3 
14 
2 
2 
16 
1 
8 
2 
9 
4 
4 
2 
6 
2 
5 
 Determine the multiple regression equation for the data and interpret the regression coefficients.
 Provide an interpretation of the coefficient of multiple determination, R2.
 At the 5% significance level, determine if # of disability days and distance between patientâ€™s residence and source of care significantly predict the number of visits.