BBH 310 exam #3 WC || with Complete Solutions.
Case-control studies differ from cross-sectional studies because they:
Don't have the same sampling procedures for all participants
Can collect information about many aspects of a person's life
Don't have a randomized control group
Can't have more than one time point correct answers Don't have the same sampling procedures
for all participants
-->The key difference is that case-control studies recruit two groups two ways, while the cross-
sectional studies recruit one group in one big sampling process.
Which of the following is not a weakness of a case-control study?
You can't study rare cases
You can have confounding due to lack of random assignment
There may be different selection biases between cases and controls
All are weaknesses
It's a retrospective study design correct answers You cant study rare cases
If the researchers evaluated the association between screen time during childhood and later risk
of obesity using a cross-sectional design, there would be both advantages and disadvantages.
Which response below correctly states a clear difference between the cohort approach and the
cross-sectional approach?
-The cross-sectional study would have better internal validity, cohort design would have poorer
internal validity
-The cohort study would allow for drawing conclusions about causality, the cross-sectional
wouldn't
-The cross-sectional study would take longer to complete, the cohort study would be faster and
easier
-The cohort study would more accurately assess childhood screen-time, the cross-sectional study
would be worse correct answers The cohort study would more accurately assess childhood
screen-time, the cross-sectional study would be worse
What study design should be chosen?
Measuring how common is Lyme disease in Pennsylvania.
Case study
Cross-sectional study
Laboratory experiment
Clinical trial
Case-control study correct answers Cross-sectional study: Prevalence in a population? Cross-
sectional will do just fine, nothing better in fact.
Identify the study design. Wright & Steinbach (2001) write: "In this paper, we describe a series
of cases that exemplify a temporal association between exposure to violence and the
precipitation of asthma exacerbations in four urban pediatric patients. In the first three cases, the
nature of the exposure is characterized by the proximity to violence, which ranged from direct
victimization (through either the threat of physical assault or actual assault) to learning of the
, death of a peer. The fourth case characterizes a scenario in which a child was exposed to severe
parental conflict (i.e., domestic violence) in the hospital setting."
case-control study
cross-sectional study
experimental study
cohort study
case study correct answers case study
What study design should be chosen?
Determining whether being a person who likes eating certain types of ethnic food raises risk for a
very rare form of cancer.
Case-control study
Cohort study
Case study
Experimental study
Cross-sectional study correct answers Case-control study
Very rare!
The percentage of all Penn State students who regularly binge drink is an example of what type
of statistic?
Incidence
Both prevalence and incidence
Neither prevalence nor incidence
Prevalence correct answers Prevalence
People participate in a study of the effects of stress on immune function. They report their stress
levels across the day and also submit saliva samples (which are analyzed for immune molecules).
This is repeated every Wednesday for 12 weeks.
Cohort
Lab experiment
Clinical trial
Cross-sectional
Case-control correct answers Cohort
Listed below are three true reasons why observational studies have advantages over experimental
studies. However, one statement is a true reason why experiments are better than observational
studies--which is it?
You have fewer problems with the ethics of manipulating variables
You have fewer problems with confounding variables
You can study the effects of dangerous drugs of abuse
You can study the effects of ethnicity correct answers You have fewer problems with
confounding variables
Which lists a person variable first and a situation variable next?
What drugs you're taking, what genes you have inherited
Case-control studies differ from cross-sectional studies because they:
Don't have the same sampling procedures for all participants
Can collect information about many aspects of a person's life
Don't have a randomized control group
Can't have more than one time point correct answers Don't have the same sampling procedures
for all participants
-->The key difference is that case-control studies recruit two groups two ways, while the cross-
sectional studies recruit one group in one big sampling process.
Which of the following is not a weakness of a case-control study?
You can't study rare cases
You can have confounding due to lack of random assignment
There may be different selection biases between cases and controls
All are weaknesses
It's a retrospective study design correct answers You cant study rare cases
If the researchers evaluated the association between screen time during childhood and later risk
of obesity using a cross-sectional design, there would be both advantages and disadvantages.
Which response below correctly states a clear difference between the cohort approach and the
cross-sectional approach?
-The cross-sectional study would have better internal validity, cohort design would have poorer
internal validity
-The cohort study would allow for drawing conclusions about causality, the cross-sectional
wouldn't
-The cross-sectional study would take longer to complete, the cohort study would be faster and
easier
-The cohort study would more accurately assess childhood screen-time, the cross-sectional study
would be worse correct answers The cohort study would more accurately assess childhood
screen-time, the cross-sectional study would be worse
What study design should be chosen?
Measuring how common is Lyme disease in Pennsylvania.
Case study
Cross-sectional study
Laboratory experiment
Clinical trial
Case-control study correct answers Cross-sectional study: Prevalence in a population? Cross-
sectional will do just fine, nothing better in fact.
Identify the study design. Wright & Steinbach (2001) write: "In this paper, we describe a series
of cases that exemplify a temporal association between exposure to violence and the
precipitation of asthma exacerbations in four urban pediatric patients. In the first three cases, the
nature of the exposure is characterized by the proximity to violence, which ranged from direct
victimization (through either the threat of physical assault or actual assault) to learning of the
, death of a peer. The fourth case characterizes a scenario in which a child was exposed to severe
parental conflict (i.e., domestic violence) in the hospital setting."
case-control study
cross-sectional study
experimental study
cohort study
case study correct answers case study
What study design should be chosen?
Determining whether being a person who likes eating certain types of ethnic food raises risk for a
very rare form of cancer.
Case-control study
Cohort study
Case study
Experimental study
Cross-sectional study correct answers Case-control study
Very rare!
The percentage of all Penn State students who regularly binge drink is an example of what type
of statistic?
Incidence
Both prevalence and incidence
Neither prevalence nor incidence
Prevalence correct answers Prevalence
People participate in a study of the effects of stress on immune function. They report their stress
levels across the day and also submit saliva samples (which are analyzed for immune molecules).
This is repeated every Wednesday for 12 weeks.
Cohort
Lab experiment
Clinical trial
Cross-sectional
Case-control correct answers Cohort
Listed below are three true reasons why observational studies have advantages over experimental
studies. However, one statement is a true reason why experiments are better than observational
studies--which is it?
You have fewer problems with the ethics of manipulating variables
You have fewer problems with confounding variables
You can study the effects of dangerous drugs of abuse
You can study the effects of ethnicity correct answers You have fewer problems with
confounding variables
Which lists a person variable first and a situation variable next?
What drugs you're taking, what genes you have inherited
