PA EPI
What is the numerical range of a P value?
0 to 1
Calculate the odds of being sedentary among the sample of individuals who do not have uterine cancer.
0.5
Compute the odds ratio and fill in the following blank: The odds of being sedentary among people with uterine cancer is ____ times as large as the odds of being sedentary among people who do not have uterine cancer.
1
Nearly _______ of cancer deaths occurring each year are attributable to poor diet and physical inactivity.
1/3
Which of the following inferences can be made based on the above data.
15 of 20 individuals who had uterine cancer were sedentary
Calculate the measure (X.X).
2
Approximately ___ to ____ min per day of moderate-to-vigorous-intensity physical activity appears necessary to reduce the risk of certain cancers.
30 to 60
About ___ of cancer is strongly hereditary.
5%
What is the relationship between the sample size and the width of the confidence interval?
As sample size increases, the width of the confidence interval decreases. There is an inverse relationship.
Suppose that a study of having a physically active lifestyle and development of obesity was conducted among 2,390 women, all of whom were initially not considered to be obese (all had a BMI of ≥30). At the start of the study, the women were surveyed to determine whether or not they currently were considered to have a sedentary lifestyle. 482 were sedentary and 1908 were not. By the end of the follow-up period, a total of 27 of the sedentary participants and 77 of the non-sedentary participants were now considered obesity. Is this a cohort study or an experimental study?
Cohort
Which gives more information: the p value or the confidence interval?
Confidence Intervals
Which of the following is NOT a true statement based on the table above.
For study c, the p value is not significant
Do these results support the hypothesis that low physical activity increases or decreases the likelihood of breast cancer?
Increases
Physical activity is an example of a __________ variable.
Independent variable
Why do many epidemiologists prefer confidence intervals over P values?
Many epidemiologists prefer confidence intervals over P values because confidence intervals give you more information and a range.
What measure of association/comparison should be used to assess the strength of the relationship between physical activity and bladder cancer?
Odds Ratio
The Framingham Heart Study enrolled a cohort of 5,209 residents of Framingham, MA who were between the ages of 30-62 and who did not have cardiovascular disease when they were enrolled. These subjects differed from one another in many ways: whether they smoked, how much they smoked, body mass index, eating habits, exercise habits, gender, family history of heart disease, etc. The researchers assessed these and many other characteristics or "exposures" soon after the subjects had been enrolled and before any of them had developed cardiovascular disease. Over time, some subjects eventually began to develop some of the outcomes of interest.
Prospective cohort
Case-control studies are best for which of the following scenarios.
Rare Diseases
Please match the following characteristics as being either similar or different between cohort studies and experimental studies.
Selection of comparison group participants= different masking of investogator= same
In which of the experimental design component is the participant unaware of treatment assignment?
Single blind and double blind study
A research design is:
The way participants are grouped and compared
What is the relationship between the sample size and P value?
There is no relationship between the p value and sample size As the sample size decreases, the p value decreases. There is an inverse relationship between the sample size and p value. As the sample size increases, the p value increases
Which of the following statements best summarizes the information in the above tables?
Though prostate cancer in men and breast cancer in women are most commonly diagnosed in the United States, lung cancer is the most deadly in both men and women.
What are the main purposes of randomization? a. To achieve baseline comparability of known and unknown confounders between the treatment and comparison groups b. To eliminate bias in assignment to treatment group c. To increase confounding between the dependent and independent variables d. To increase sample size
a and b
A small hypothetical case-control study identified 20 individuals that had uterine cancer. Of these individuals, 15 indicated that they were sedentary. 40 Spouses who have not ever been diagnosed with cancer were then recruited to be controls for the study. Of the spouses, 30 reported that they were sedentary. a b c d
a= 15 b=30 c=5 d=10
Suppose that a case-control study was conducted to evaluate the relationship between low vs. high levels of physical activity and breast cancer. Among the cases, 630 reported low physical activity in the past, while 181 had reported high physical activity. Of the controls, 736 reported low physical activity and 434 reported high physical activity. a= b= c= d=
a= 630 b= 736 c= 181 d= 434
A small hypothetical case-control study identified 20 individuals that had uterine cancer. Of these individuals, 15 indicated that they were sedentary. a b c d
a=15 b= not enough info c= 5 d= not enough information
Cross-sectional surveys, sometimes called prevalence studies, measure both risk factors and the presence or absence of disease ____.
at the same point in time
Which of the following cancers are the most impacted by physical activity? (i.e. Strong scientific evidence supports the relationship of physical activity with these types of cancers.)
colon and breast
When change in the independent variable is manipulated by the investigator, the design is _____.
experimental
For cohort studies, eligible subjects have to meet certain criteria to be included as subjects in a study. This is called null-exclusion criteria.
false
When compliance is poor it increases your ability to detect a true difference between the groups?
false
In Epidemiology, a cohort is a group of individuals who are _________________.
followed over a period of time.
From the following three types of comparison groups, which of these is considered the "best" source for comparison group:
internal
Match the following term with the correct definition. independent dependent
manipulated or flucuating the outcome variable
At the completion of a study, a statistical test was performed and a P value of 0.052 was obtained. Are these results considered "statistically significant" by conventional criteria?
no
Given the above information, do you have enough information to support that a sedentary lifestyle can increase one's risk of uterine cancer?
no
In a study that looked lung cancer and physical activity participation, the 95% confidence interval for the OR extended from 0.89 to 1.36. Are these results considered "statistically significant" by conventional criteria?
no
One of the basic requirements of a cohort type study is that... (select all that apply)
none of the subjects have the outcome of interest at the beginning of the follow-up period time must pass in order to determine the frequency of developing the outcome
Almost half of men (44%) and over a third of women (38%) in the United States will develop some form of cancer during their lifetimes.
true
There is no standard rule for how to set up contingency tables, and you will see them set up in different ways in journal articles, textbooks, and reports.
true
Using a placebo makes the treatment and comparison groups comparable with respect to their study "experience."
true
At the completion of a study, a statistical test was performed and a P value of 0.001 was obtained. Are these results considered "statistically significant" by conventional criteria?
yes
In a study that looked at physical activity participation at low SES and high SES community recreation centers, the 95% confidence interval for the OR extended from 2.00 to 5.26. Are these results considered "statistically significant" by conventional criteria?
yes
