General Hospital Biostatistics Assignment: Analysis of Medical Records

This assignment presents a series of biostatistics questions based on a case-control study using medical records from a general hospital. The questions cover various aspects of study design, including identifying the study type, disease outcome, and exposure. Students are asked to calculate odds for exposed subjects, compute the odds ratio, and analyze data from a table of patient height and weight, calculating measures of central tendency, dispersion, and confidence intervals. Furthermore, questions address the appropriate graph for data representation, the impact of sample size on precision, data measurement levels, and the application of the central limit theorem. Finally, the assignment includes questions on statistical process control charts for monitoring blood glucose levels and unplanned extubation rates.

Question 14 pts
Using ICD-9 codes from General Hospital medical records, subjects suffering from
acute myocardial infarction (ICD-9 code 410) were identified. Using the same hospital
database, for each person identified that had suffered acute myocardial infarction, a
person of the same age and gender that had never had acute myocardial infarction was
identified. All of these subjects’ medical records were then examined to ascertain
whether or not the person had ever been diagnosed with “hypertensive disease” (ICD-9
code 401-405) prior to the acute myocardial infarction. The findings were:
 173 subjects suffering from acute myocardial infarction, 59 of which had
hypertensive disease
 173 subjects never suffering from acute myocardial infarction, 25 of which had
hypertensive disease
1A) What kind of study is this?
Group of answer choices
Quasi-experimental study
Case-control study
Retrospective Cohort study
Prospective cohort study
Randomized clinical trial
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Question 24 pts
Using ICD-9 codes from General Hospital medical records, subjects suffering from
acute myocardial infarction (ICD-9 code 410) were identified. Using the same hospital
database, for each person identified that had suffered acute myocardial infarction, a
person of the same age and gender that had never had acute myocardial infarction was
identified. All of these subjects’ medical records were then examined to ascertain
whether or not the person had ever been diagnosed with “hypertensive disease” (ICD-9
code 401-405) prior to the acute myocardial infarction. The findings were:

 173 subjects suffering from acute myocardial infarction, 59 of which had
hypertensive disease
 173 subjects never suffering from acute myocardial infarction, 25 of which had
hypertensive disease
 1B) What is the “disease” outcome in this study?
Group of answer choices
Hypertension
Acute myocardial infarction
Male gender
Old age
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Question 34 pts
Using ICD-9 codes from General Hospital medical records, subjects suffering from
acute myocardial infarction (ICD-9 code 410) were identified. Using the same hospital
database, for each person identified that had suffered acute myocardial infarction, a
person of the same age and gender that had never had acute myocardial infarction was
identified. All of these subjects’ medical records were then examined to ascertain
whether or not the person had ever been diagnosed with “hypertensive disease” (ICD-9
code 401-405) prior to the acute myocardial infarction. The findings were:
 173 subjects suffering from acute myocardial infarction, 59 of which had
hypertensive disease
 173 subjects never suffering from acute myocardial infarction, 25 of which had
hypertensive disease
1C) What is the "exposure" in this study?
Group of answer choices
Acute myocardial infarction

Hypertension
Old age
Male Gender
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Question 44 pts
Using ICD-9 codes from General Hospital medical records, subjects suffering from
acute myocardial infarction (ICD-9 code 410) were identified. Using the same hospital
database, for each person identified that had suffered acute myocardial infarction, a
person of the same age and gender that had never had acute myocardial infarction was
identified. All of these subjects’ medical records were then examined to ascertain
whether or not the person had ever been diagnosed with “hypertensive disease” (ICD-9
code 401-405) prior to the acute myocardial infarction. The findings were:
 173 subjects suffering from acute myocardial infarction, 59 of which had
hypertensive disease
 173 subjects never suffering from acute myocardial infarction, 25 of which had
hypertensive disease
1D) What are the odds for exposed subjects to develop disease? (Round to one
decimal place)
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Question 54 pts
Using ICD-9 codes from General Hospital medical records, subjects suffering from
acute myocardial infarction (ICD-9 code 410) were identified. Using the same hospital
database, for each person identified that had suffered acute myocardial infarction, a
person of the same age and gender that had never had acute myocardial infarction was
identified. All of these subjects’ medical records were then examined to ascertain
whether or not the person had ever been diagnosed with “hypertensive disease” (ICD-9
code 401-405) prior to the acute myocardial infarction. The findings were:
 173 subjects suffering from acute myocardial infarction, 59 of which had
hypertensive disease
0.3

 173 subjects never suffering from acute myocardial infarction, 25 of which had
hypertensive disease
1E) Calculate the odds ratio. (Round to one decimal place)
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Question 64 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
3 female 65 204
4 male 72 255
5 male 66 186
Height and weight of five consecutive patients visiting a local clinic.
2A) Which type of graph would be most appropriate for displaying the relationship
between height and weight using the data in the table?
Group of answer choices
Scatterplot
Box plot
Bar chart
Histogram
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Question 74 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
3 female 65 204
4 male 72 255
5 male 66 186
2.4

Use the Weight data to answer the following:
2B) Sample size n = ___5______
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Question 84 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
3 female 65 204
4 male 72 255
5 male 66 186
2C) The median is ____200___ pounds.
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Question 94 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
3 female 65 204
4 male 72 255
5 male 66 186
2D) The mean is ______200.4___ pounds. (Round to one decimal place)
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Question 104 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
5
200
200.4

3 female 65 204
4 male 72 255
5 male 66 186
2E) The range is ______98___ pounds.
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Question 114 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
3 female 65 204
4 male 72 255
5 male 66 186
2F) The sample variance is __1271.3__________. (Round to one decimal place)
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Question 124 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
3 female 65 204
4 male 72 255
5 male 66 186
2G) The sample standard deviation is _____35.7___ pounds. (Round to one decimal
place)
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98
1 127 .3
35.7

Question 134 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
3 female 65 204
4 male 72 255
5 male 66 186
2H) The standard error of the mean (SEM) is _______15.9_____. (Round to one
decimal place)
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Question 144 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
3 female 65 204
4 male 72 255
5 male 66 186
95 % CI on μ: = xbar ± tdf (SEM)
Where df for a CI on μ is n-1
*refer to the t-table to get tdf
2I) The lower bound on the 95% confidence interval on the mean weight of the patients is ____156___ pounds. (Round to the nearest whole number)
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Question 154 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
15.9
156

3 female 65 204
4 male 72 255
5 male 66 186
2J) The upper bound on the 95% confidence interval on the mean weight of the patients
is ___245_______ pounds. (Round to the nearest whole number)
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Question 164 pts
2K) The researcher complains that the 95% confidence intervals are too wide to be
useful. What can you tell her to do to improve the precision?
Group of answer choices
Measure the weight more accurately
Nothing can be done to improve the precision
Increase the sample size
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Question 174 pts
2L) Which of the following is necessary for a valid estimate of the population mean
weight?
Group of answer choices
No measurement error
No sample bias
No random variation
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Question 184 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
245

3 female 65 204
4 male 72 255
5 male 66 186
2M) in the table, what best describes the level of data measurement for "gender"?
Group of answer choices
Continuous
Ordinal
Nominal
Dichotomous
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Question 194 pts
Subject ID Gender Height (inches) Weight (pounds)
1 male 70 200
2 female 61 157
3 female 65 204
4 male 72 255
5 male 66 186
2N) In the table, what best describes the level of data measurement for "height"?
Group of answer choices
Dichotomous
Ordinal
Nominal
Continuous
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Question 208 pts

3. A researcher has been collecting serum specimens and measuring levels of a newly
discovered biomarker thought to be associated with a metabolic syndrome. After
constructing a histogram, she discovers that the distribution of observations from her
sample of biomarker measurements is highly right-skewed. The researcher plans to
further investigate the biomarker by collecting samples from patients at over 250
hospitals and clinics across the nation. Based on your knowledge of the central limit
theorem, what can you tell the researcher about the distribution you'd expect to see if
she creates a histogram of the sample mean of the biomakre levels from each
hospital/clinic, where each hospital/clinic has data on a minimum of 100 patients'
biomarker levels? The distribution of the 250 sample means should be which of the
following?
Group of answer choices
Left-skewed
Symmetrical
Right-skewed
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Question 218 pts
4. Rebecca has been recently diagnosed with type 2 diabetes mellitus and placed on
metformin therapy. She wants to use a control chart to track her daily morning fasting
blood glucose level so that she can detect any signals of special cause variation. Which
is the appropriate type of statistical process control chart for this purpose?
Group of answer choices
G chart
X-bar chart
S chart
C chart
U chart
P chart
I chart
R chart

T chart
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Question 228 pts
5. A local hospital has started using a new method for securing endotracheal tubes in
the NICU. What is the appropriate type of statistical process control chart to use to see
if there is a change in the unplanned extubation rate?
Group of answer choices
R chart
X-bar chart
I chart
G chart
T chart
P chart
C chart
S chart
U chart