Homework assignment seminar 4
Assignment 1
experimental study would be unethical because intentionally subjecting medical trainees to
extended work hours or exposing them to potential injury risks would violate ethical research
standards. With a case-control study there could be recall-bias
study population: 2737 students, exposure measurements: comprehensive Web-based surveys
that asked about work schedules and the occurrence of percutaneous injuries in the previous
month were sent to all participants. Outcome measurements: Comparisons of rates of
percutaneous injuries during day work (6:30 am to 5:30 pm) after working overnight (extended
work) vs day work that was not preceded by working overnight (nonextended work) Main analysis:
Case-crossover within-subjects analyses were performed, they compared the rate of percutaneous
injuries during extended work periods, versus non extended work periods
step 1: selection of the population at risk and the study population
step 2: baseline data collection
step 3: monitoring of working hours
step 4: tracking percutaneous injuries
step 5: data-analysis
step 6: conlusion
Assignment 2
2.1 Yes, a case-control study was justified because sudden cardiac death is a rare death and
therefore, they can’t use a prospective cohort design. They can’t use a RCT either, because that
would be unethical. So, therefore a case-control
2.2 step 1: identifying the potential cases
Step 2: identifying the potential control group
Step 3: choose the measurement of exposure
Step 4: choose the measurement of outcome
Step 5: conclusion
2.3 A suitable base population for a case-control study should ideally represent the population from
which the cases arose and should be at risk of developing the same outcome. In this study, the
cases were Caucasian women aged 25-64 years in Allegheny County, Pennsylvania, who died
suddenly from arteriosclerotic heart disease (ASHD).
2.4 In a case-control study, it is crucial to measure certain characteristics consistently across cases
and controls to ensure comparability and reduce bias. Key characteristics that must be measured
similarly include:
1. Exposure to the risk factor
2. Demographic variables
3. Medical and lifestyle factors
4. Psychosocial stress and coping mechanisms
While Cottington et al. made efforts to measure bereavement similarly, challenges like recall bias,
confounding, and lack of direct psychosocial stress measurement may have impacted the validity of
the findings
Assignment 1
experimental study would be unethical because intentionally subjecting medical trainees to
extended work hours or exposing them to potential injury risks would violate ethical research
standards. With a case-control study there could be recall-bias
study population: 2737 students, exposure measurements: comprehensive Web-based surveys
that asked about work schedules and the occurrence of percutaneous injuries in the previous
month were sent to all participants. Outcome measurements: Comparisons of rates of
percutaneous injuries during day work (6:30 am to 5:30 pm) after working overnight (extended
work) vs day work that was not preceded by working overnight (nonextended work) Main analysis:
Case-crossover within-subjects analyses were performed, they compared the rate of percutaneous
injuries during extended work periods, versus non extended work periods
step 1: selection of the population at risk and the study population
step 2: baseline data collection
step 3: monitoring of working hours
step 4: tracking percutaneous injuries
step 5: data-analysis
step 6: conlusion
Assignment 2
2.1 Yes, a case-control study was justified because sudden cardiac death is a rare death and
therefore, they can’t use a prospective cohort design. They can’t use a RCT either, because that
would be unethical. So, therefore a case-control
2.2 step 1: identifying the potential cases
Step 2: identifying the potential control group
Step 3: choose the measurement of exposure
Step 4: choose the measurement of outcome
Step 5: conclusion
2.3 A suitable base population for a case-control study should ideally represent the population from
which the cases arose and should be at risk of developing the same outcome. In this study, the
cases were Caucasian women aged 25-64 years in Allegheny County, Pennsylvania, who died
suddenly from arteriosclerotic heart disease (ASHD).
2.4 In a case-control study, it is crucial to measure certain characteristics consistently across cases
and controls to ensure comparability and reduce bias. Key characteristics that must be measured
similarly include:
1. Exposure to the risk factor
2. Demographic variables
3. Medical and lifestyle factors
4. Psychosocial stress and coping mechanisms
While Cottington et al. made efforts to measure bereavement similarly, challenges like recall bias,
confounding, and lack of direct psychosocial stress measurement may have impacted the validity of
the findings
