Proportional Mortality Ratio

Proportional Mortality Ratio

Quiz

Question 1. 

In a population of 534,533 White male roadside construction workers, 436 died from Lung Disease in 1980.  Is this mortality experience from Lung Disease greater than, less than, or about the same as that which you would expect in White males of the same ages in the general population?  Use Table 1 to answer the question.  

Question 2.

Given that the crude death rate in White male roadside construction workers is 11 per 1000, what is the Indirect Adjusted Mortality Rate (IAR) of the White male roadside construction workers compared to the general population of White males?

TABLE 1: Data on White Male Disease on Mortality
Age (Yrs) Estimated Population for White Male Roadside Construction Workers Death Rate Per 100,000 from Lung Disease in White Males (General Population) Expected Deaths from Lung Disease in White Roadside Construction Workers (If Same Risk as General Population) Observed Deaths from Lung Disease in White Roadside Construction Workers (If Same Risk as General Population)
20–24 74,598 12.26 10
25-29 85,077 15.45 20
30-34 80,845 22.55 22
35-44 148,870 34.84 98
45-54 102,649 57.57 112
55-59 42,494 74.31 174

Question 3.

The total population in 2003 was 290,810,789 (males = 143,037,290; females=147,773,499).  For 2003, the total number of live births was 4,089,950.  

Total Mortality from Selected Causes, Males and Females, United States, 2003

Causes of Death Males  Females Total
All Causes 1,201,964 1,246,324 2,448,288
Accidents 70,532 38,745 109,277
Malignant Neoplasms 287,990 268,912 556,902
Alzheimer’s Disease 18,335 45,122 63,457
Infant Deaths 15,902 12,123 28,025
Maternal Deaths NA 495 495

 

  1. a)   Calculate the crude death rates (per 100,000) and the cause-specific death rates (per 100,000) for accidents, malignant neoplasms, and Alzheimer’s Disease.  Repeat these calculations for males and females separately. Place your answers in the table below.
    Male Death

Rate (per 100,000)

  Female Death Rate (per 100,000)   Total Death Rate (per 100,000)
All Causes 1,201,964 1,246,324 2,448,288
Accidents 70,532 38,745 109,277
Malignant Neoplasms 287,990 268,912 556,902
Alzheimer’s Disease 18,335 45,122 63,457

 

  1. b)   What are the Proportional Mortality Ratio (PMRs) (Percent) for accidents, malignant neoplasms, and Alzheimer’s Disease? Repeat these calculations for males and females separately. Place your answers in the table below.
Males Females Total
Accidents
Malignant Neoplasms
Alzheimer’s Disease

 

  1. c)     Calculate the maternal mortality rate (per 100,000 live births).
  2. d)     Calculate the infant mortality rate (per 1000 live births).
  3. e)     Calculate the crude birth rate (per 1000 population).

Question 4. 

In case-control studies, the odds ratio is used as an estimate of the relative risk. In order for this approximation to be reasonable, some conditions must be met. Which of the following conditions is not necessary in order to use the odds ratio to estimate the relative risk?

 a. With respect to exposure, controls are representative of the population to which you want to generalize your results.
 b. The event (disease) under study is rare in the population.
 c. Cases are representative of all cases.
 d. The exposure in question is rare in the population.

Question 5.

An epidemiologic survey of Motor Vehicle Accidents (MVA) in Metroville, a city with a population of 100,000 (during the midpoint of the year), produced the following data for a particular year: 

Number of drivers in Metroville during any given month 12,000
Total number of residents injured from MVA 1,800
Total number of deaths from MVA 90
Total number of deaths from all causes 900

The proportional mortality ratio (%) due to motor vehicles was:

a. 90/1,800 x 100
b. 90/100,000 x 100
c. 90/600 x 100
d. 90/900 x 100

Question 6.

An epidemiologic survey of Motor Vehicle Accidents (MVA) in Metroville, a city with a population of 100,000 (during the midpoint of the year), produced the following data for a particular year:

Number of drivers in Metroville during any given month 12,000
Total number of residents injured from MVA 1,800
Total number of deaths from MVA 90
Total number of deaths from all causes 900

The crude death rate for all causes was:

 a. 90/600 x 100,000
 b. 900/100,000 x 100,000
 c. 90/1,800 x 100,000
 d. 90/900 x 100,000

Question 7. 

A large medical center’s oncology program reported an increased number of cases of pancreatic cancer during a certain month. The hospital’s epidemiologist decided to research the problem. Tumor registry records were searched to identify all cases of pancreatic cancer during a five-year period; cancer patients were matched with patients treated for other diseases during the same five-year period. All subjects in the study were questioned about lifestyle factors including alcohol, tea, and coffee consumption. The resulting data are as follows:

DATA
Cancer Patients Other Patients
Men Women Men Women
LIFESTYLE VARIABLE
Alcohol 185 120 270 260
Tea Drinking 140 110 230 225
Coffee Drinking 190 140 270 240

Note: Total number of male cancer patients = 200.

Total number of female cancer patients = 150.

Total number of male patients (other diseases) = 300.

Total number of female patients (other diseases) = 300.

Which number best approximates risk associated with Coffee Drinking in Men?

a. 1.02
b. 3.50
c.  0.94
d.  2.11
 e. 0.63

Question 8.

A large medical center’s oncology program reported an increased number of cases of pancreatic cancer during a certain month. The hospital’s epidemiologist decided to research the problem. Tumor registry records were searched to identify all cases of pancreatic cancer during a five-year period; cancer patients were matched with patients treated for other diseases during the same five-year period. All subjects in the study were questioned about lifestyle factors including alcohol, tea, and coffee consumption. The resulting data are as follows:

DATA
Cancer Patients Other Patients
Men Women Men Women
LIFESTYLE VARIABLE
Alcohol 185 120 270 260
Tea Drinking 140 110 230 225
Coffee Drinking 190 140 270 240

Note: Total number of male cancer patients = 200.

Total number of female cancer patients = 150.

Total number of male patients (other diseases) = 300.

Total number of female patients (other diseases) = 300.

Which number best approximates risk associated with Coffee Drinking in Women? 

a. 0.94
b. 3.50
c. 0.63
 d. 2.11
 e.1.02

Question 9.

A large medical center’s oncology program reported an increased number of cases of pancreatic cancer during a certain month. The hospital’s epidemiologist decided to research the problem. Tumor registry records were searched to identify all cases of pancreatic cancer during a five-year period; cancer patients were matched with patients treated for other diseases during the same five-year period. All subjects in the study were questioned about lifestyle factors including alcohol, tea, and coffee consumption.

The resulting data are as follows:

DATA
Cancer Patients Other Patients
Men Women Men Women
LIFESTYLE VARIABLE
Alcohol 185 120 270 260
Tea Drinking 140 110 230 225
Coffee Drinking 190 140 270 240

Note: Total number of male cancer patients = 200.

Total number of female cancer patients = 150.

Total number of male patients (other diseases) = 300.

Total number of female patients (other diseases) = 300.

Does this study have an exposure status variable? 

 a. No
 b. Yes, disease type
 c. Insufficient information to answer this question
 d. Yes, sex of patient
 e. Yes, lifestyle

Question 10. 

A large medical center’s oncology program reported an increased number of cases of pancreatic cancer during a certain month. The hospital’s epidemiologist decided to research the problem. Tumor registry records were searched to identify all cases of pancreatic cancer during a five-year period; cancer patients were matched with patients treated for other diseases during the same five-year period. All subjects in the study were questioned about lifestyle factors including alcohol, tea, and coffee consumption.

The resulting data are as follows:

DATA
Cancer Patients Other Patients
Men Women Men Women
LIFESTYLE VARIABLE
Alcohol 185 120 270 260
Tea Drinking 140 110 230 225
Coffee Drinking 190 140 270 240

Note: Total number of male cancer patients = 200.

Total number of female cancer patients = 150.

Total number of male patients (other diseases) = 300.

Total number of female patients (other diseases) = 300.

Which number best approximates risk associated with alcohol drinking in men? 

a  0.71
b. 0.92
c. 2.11
d.1.37
e. 0.62

Question 11. 

A large medical center’s oncology program reported an increased number of cases of pancreatic cancer during a certain month. The hospital’s epidemiologist decided to research the problem. Tumor registry records were searched to identify all cases of pancreatic cancer during a five-year period; cancer patients were matched with patients treated for other diseases during the same five-year period. All subjects in the study were questioned about lifestyle factors including alcohol, tea, and coffee consumption. 

The resulting data are as follows:

DATA
Cancer Patients Other Patients
Men Women Men Women
LIFESTYLE VARIABLE
Alcohol 185 120 270 260
Tea Drinking 140 110 230 225
Coffee Drinking 190 140 270 240

Note: Total number of male cancer patients = 200.

Total number of female cancer patients = 150.

Total number of male patients (other diseases) = 300.

Total number of female patients (other diseases) = 300.

 

What type of study is this? 

a. Cohort
b.Experimental
c. Clinical trial
 

d. Case-control

 

e. Intervention

Question 12.  

A case-control study is purely a descriptive (as opposed to analytic) study design. 

  1. True
  2. False 

Question 13. 

a. This type of study is the strongest at proving or disproving association and allows the researcher to control exposure to cases and controls. Examples of this type of study include clinical trials for vaccines.

  1. Examples of this type of a study include BRFSS, NHANES, PRAMS.
  1. This is not a study but a form of epidemiology that includes analyzing rates, proportions, and ratios.
  1. This type of study is most often used with testing a null hypothesis for an outbreak since you know the outcome/disease and who are the cases.
  1. This is the weakest study but can be the start to further testing the association between a risk/exposure and disease/disability/death.
  1. This type of study follows a group of people over a length of time to determine if certain exposures result in certain outcomes. Example of this type of study is the Framingham Nurse Study.

Solution

 Question 1. 

In a population of 534,533 White male roadside construction workers, 436 died from Lung Disease in 1980.  Is this mortality experience from Lung Disease greater than, less than, or about the same as that which you would expect in White males of the same ages in the general population?  Use Table 1 to answer the question.

Answer 1. By multiplying the death rate with the estimated population, we get the expected deaths from Lung Disease in White Males for the General Population. The values are lesser than the observed deaths in each category. Standard Mortality Rate=2.38 

Question 2.

Given that the crude death rate in White male roadside construction workers is 11 per 1000, what is the Indirect Adjusted Mortality Rate (IAR) of the White male roadside construction workers compared to the general population of White males?

Answer 2. IAR=Crude Death Rate x SMR

=11 x 2.38=26.18 (per 1000)

TABLE 1: Data on White Male Disease on Mortality
Age (Yrs) Estimated Population for White Male Roadside Construction Workers Death Rate Per 100,000 from Lung Disease in White Males (General Population) Expected Deaths from Lung Disease in White Roadside Construction Workers (If Same Risk as General Population) Observed Deaths from Lung Disease in White Roadside Construction Workers (If Same Risk as General Population)
20–24 74,598 12.26 9.1457148 10
25-29 85,077 15.45 13.1443965 20
30-34 80,845 22.55 18.2305475 22
35-44 148,870 34.84 51.866308 98
45-54 102,649 57.57  59.0950293 112
55-59 42,494 74.31  31.5772914 174

Question 3.

The total population in 2003 was 290,810,789 (males = 143,037,290; females=147,773,499).  For 2003, the total number of live births was 4,089,950.  

Total Mortality from Selected Causes, Males and Females, United States, 2003

Causes of Death Males  Females Total
All Causes 1,201,964 1,246,324 2,448,288
Accidents 70,532 38,745 109,277
Malignant Neoplasms 287,990 268,912 556,902
Alzheimer’s Disease 18,335 45,122 63,457
Infant Deaths 15,902 12,123 28,025
Maternal Deaths NA 495 495

a)   Calculate the crude death rates (per 100,000) and the cause-specific death rates (per 100,000) for accidents, malignant neoplasms, and Alzheimer’s Disease.  Repeat these calculations for males and females separately. Place your answers in the table below.

    Male Death

Rate (per 100,000)

  Female Death Rate (per 100,000)   Total Death Rate (per 100,000)
All Causes 1,201,964 840.315 1,246,324 843.401 2,448,288 841.883
Accidents 70,532 49.3102 38,745 26.2192 109,277 37.5766
Malignant Neoplasms 287,990 201.339 268,912 181.976 556,902 191.500
Alzheimer’s Disease 18,335 12.8183 45,122 30.5345 63,457  21.8104

b)   What are the Proportional Mortality Ratio (PMRs) (Percent) for accidents, malignant neoplasms, and Alzheimer’s Disease? Repeat these calculations for males and females separately. Place your answers in the table below.

Males Females Total
Accidents 5.86%  3.11%  4.46%
Malignant Neoplasms  23.9%  21.5% 22.7%
Alzheimer’s Disease 1.52%  3.6%  2.5%

c)     Calculate the maternal mortality rate (per 100,000 live births).

Answer 3.c) 12.10283 per 100,000 live births

  1. d)     Calculate the infant mortality rate (per 1000 live births).

Answer 3.d) 6.85216 per 1000 live births

  1. e)     Calculate the crude birth rate (per 1000 population).

Answer 3.e) 14.06395 per 1000 population

Question 4. 

In case-control studies, the odds ratio is used as an estimate of the relative risk. In order for this approximation to be reasonable, some conditions must be met. Which of the following conditions is not necessary in order to use the odds ratio to estimate the relative risk?

 a. With respect to exposure, controls are representative of the population to which you want to generalize your results.
 b. The event (disease) under study is rare in the population.
 c. Cases are representative of all cases.
 d. The exposure in question is rare in the population.

 

Answer 4. d. The exposure in question is rare in the population.

Question 5.

An epidemiologic survey of Motor Vehicle Accidents (MVA) in Metroville, a city with a population of 100,000 (during the midpoint of the year), produced the following data for a particular year: 

Number of drivers in Metroville during any given month 12,000
Total number of residents injured from MVA 1,800
Total number of deaths from MVA 90
Total number of deaths from all causes 900

The proportional mortality ratio (%) due to motor vehicles was:

a. 90/1,800 x 100
b. 90/100,000 x 100
c. 90/600 x 100
d. 90/900 x 100

Answer 5.d. 90/900 x 100

Question 6.

An epidemiologic survey of Motor Vehicle Accidents (MVA) in Metroville, a city with a population of 100,000 (during the midpoint of the year), produced the following data for a particular year:

Number of drivers in Metroville during any given month 12,000
Total number of residents injured from MVA 1,800
Total number of deaths from MVA 90
Total number of deaths from all causes 900

The crude death rate for all causes was:

 a. 90/600 x 100,000
 b. 900/100,000 x 100,000
 c. 90/1,800 x 100,000
 d. 90/900 x 100,000
 

 

Answer 6. b. 900/100,000 x 100,000

Question 7. 

A large medical center’s oncology program reported an increased number of cases of pancreatic cancer during a certain month. The hospital’s epidemiologist decided to research the problem. Tumor registry records were searched to identify all cases of pancreatic cancer during a five-year period; cancer patients were matched with patients treated for other diseases during the same five-year period. All subjects in the study were questioned about lifestyle factors including alcohol, tea, and coffee consumption. The resulting data are as follows:

DATA
Cancer Patients Other Patients
Men Women Men Women
LIFESTYLE VARIABLE
Alcohol 185 120 270 260
Tea Drinking 140 110 230 225
Coffee Drinking 190 140 270 240

Note: Total number of male cancer patients = 200.

Total number of female cancer patients = 150.

Total number of male patients (other diseases) = 300.

Total number of female patients (other diseases) = 300.

Which number best approximates risk associated with Coffee Drinking in Men?

a. 1.02
b. 3.50
c.  0.94
d.  2.11
 e. 0.63

Answer 7. d. 2.11

Question 8.

A large medical center’s oncology program reported an increased number of cases of pancreatic cancer during a certain month. The hospital’s epidemiologist decided to research the problem. Tumor registry records were searched to identify all cases of pancreatic cancer during a five-year period; cancer patients were matched with patients treated for other diseases during the same five-year period. All subjects in the study were questioned about lifestyle factors including alcohol, tea, and coffee consumption. The resulting data are as follows:

DATA
Cancer Patients Other Patients
Men Women Men Women
LIFESTYLE VARIABLE
Alcohol 185 120 270 260
Tea Drinking 140 110 230 225
Coffee Drinking 190 140 270 240

Note: Total number of male cancer patients = 200.

Total number of female cancer patients = 150.

Total number of male patients (other diseases) = 300.

Total number of female patients (other diseases) = 300.
Which number best approximates risk associated with Coffee Drinking in Women? 

a. 0.94
b. 3.50
c. 0.63
 d. 2.11
 e.1.02

Answer 8. b. 3.50

Question 9.

A large medical center’s oncology program reported an increased number of cases of pancreatic cancer during a certain month. The hospital’s epidemiologist decided to research the problem. Tumor registry records were searched to identify all cases of pancreatic cancer during a five-year period; cancer patients were matched with patients treated for other diseases during the same five-year period. All subjects in the study were questioned about lifestyle factors including alcohol, tea, and coffee consumption.

The resulting data are as follows:

DATA
Cancer Patients Other Patients
Men Women Men Women
LIFESTYLE VARIABLE
Alcohol 185 120 270 260
Tea Drinking 140 110 230 225
Coffee Drinking 190 140 270 240

Note: Total number of male cancer patients = 200.

Total number of female cancer patients = 150.

Total number of male patients (other diseases) = 300.

Total number of female patients (other diseases) = 300.

Does this study have an exposure status variable? 

 a. No
 b. Yes, disease type
 c. Insufficient information to answer this question
 d. Yes, sex of patient
 e. Yes, lifestyle

Answer 9. e. Yes, lifestyle

Question 10. 

A large medical center’s oncology program reported an increased number of cases of pancreatic cancer during a certain month. The hospital’s epidemiologist decided to research the problem. Tumor registry records were searched to identify all cases of pancreatic cancer during a five-year period; cancer patients were matched with patients treated for other diseases during the same five-year period. All subjects in the study were questioned about lifestyle factors including alcohol, tea, and coffee consumption.

The resulting data are as follows:

DATA
Cancer Patients Other Patients
Men Women Men Women
LIFESTYLE VARIABLE
Alcohol 185 120 270 260
Tea Drinking 140 110 230 225
Coffee Drinking 190 140 270 240

Note: Total number of male cancer patients = 200.

Total number of female cancer patients = 150.

Total number of male patients (other diseases) = 300.

Total number of female patients (other diseases) = 300.
Which number best approximates risk associated with alcohol drinking in men? 

a  0.71
b. 0.92
c. 2.11
d.1.37
e. 0.62
Answer 10. d.1.37

Question 11. 

A large medical center’s oncology program reported an increased number of cases of pancreatic cancer during a certain month. The hospital’s epidemiologist decided to research the problem. Tumor registry records were searched to identify all cases of pancreatic cancer during a five-year period; cancer patients were matched with patients treated for other diseases during the same five-year period. All subjects in the study were questioned about lifestyle factors including alcohol, tea, and coffee consumption. 

The resulting data are as follows:

DATA
Cancer Patients Other Patients
Men Women Men Women
LIFESTYLE VARIABLE
Alcohol 185 120 270 260
Tea Drinking 140 110 230 225
Coffee Drinking 190 140 270 240

Note: Total number of male cancer patients = 200.

Total number of female cancer patients = 150.

Total number of male patients (other diseases) = 300.

Total number of female patients (other diseases) = 300.

What type of study is this? 

a. Cohort
b.Experimental
c. Clinical trial
 

d. Case-control

 

e. Intervention

Answer 11. d. Case-control

Question 12.  

A case-control study is purely a descriptive (as opposed to analytic) study design. 

  1. True
  2. False

Answer 12. b. False 

Question 13. 

a. This type of study is the strongest at proving or disproving association and allows the researcher to control exposure to cases and controls. Examples of this type of study include clinical trials for vaccines.

Answer 13. a. Cohort Study

  1. Examples of this type of a study include BRFSS, NHANES, PRAMS.

Answer 13. b. CDC Cross-sectional surveys

  1. This is not a study but a form of epidemiology that includes analyzing rates, proportions, and ratios.

Answer 13 c. Occupational Epidemiology Study

  1. This type of study is most often used with testing a null hypothesis for an outbreak since you know the outcome/disease and who are the cases.

Answer 13. d. Retrospective Cohort Study

  1. This is the weakest study but can be the start to further testing the association between a risk/exposure and disease/disability/death.

Answer 13. e. Cross-Sectional Study

  1. This type of study follows a group of people over a length of time to determine if certain exposures result in certain outcomes. Example of this type of study is the Framingham Nurse Study.

Answer 13. f. Prospective Cohort Study