Epidemiology-McFarland Flashcards
What studies are descriptive studies?
- surveillance
- case studies
- cross-sectional
- ecologic
What studies are analytic studies?
Experimental
-Clinical trial
-Community
Observational
-Cohort
*Prospective and Restrospective
-Case-ControlWhat do case-control studies tell you?
determinants of disease
What do ecologic studies tell you?
Distribution of disease
What is this:
collects data from a group of people to assess frequency of disease (and related risk factors) at a particular point in time.
Asks “what is happening?”
Cross-sectional study
-Observational
What is this:
Compares a group of people with a disease to a group without disease. Looks for prior exposure or risk factor. Asks “what happened?”
Case-control study (observational and retrospective)
What does a cross-sectional study measure?
-Disease prevalence
Can show risk factor association with disease, but does not establish causality
What does a case-control study measure?
-Odds ratio (OR)
Patients with COPD had higher odds of history of smoking than those without COPD had
What is this:
Compares a group with a given exposure or risk factor to a group without such exposure. Looks to see if exposure increases the likelihood of disease. Can be prospective (asks “who will develop disease?”) or retrospective (asks, “who developed the disease (exposed vs nonexposed?”)
Cohort Study
What does a cohort study measure?
relative risk (RR) "smokers had a higher risk of developing COPD than nonsmokers had"
What is this:
(# of existing cases of a disease)/(# in candidate population)
Over a specified period of time
Prevalence
What is this:
(# of new cases of a disease)/(# in candidate population)
Over a specified period of time
Cumulative Incidence (incidence proportion)
What is this:
of new cases of a disease
incidence rate
What are the relative measures of comparison?
Ratios
- prevalence ratio
- risk ratio
- rate ratio
- odds ratio
What are the absolute measures of comparison?
- prevalence difference
- risk difference
- rate difference
In case control studies you use a (blank) ratio
odds
What does temporality tell you?
whether there is evidence that exposure preceded disease
If you have a P value less than .001 then what does this mean?
The null hypothesis is rejected
How do you increase external validity?
- Use random sampling
- Use large sample sizes
- High response rate
What is this:
all cases are not detected at the same stage of the disease (cancer)
lead-time bias
What is this:
if a subject knows that he/she is being observed or being investigated, their behavior and response can change
Hawthorne Effect
What three things must confounding variables be associated with?
- associated with exposure (causally or non-causally)
- associated (causally) with the outcome, independent of the exposure
- Not be an intermediate variable in the causal pathway
Whats the most common cause of death in Nevada?
Diseases of the heart
typically older (greater than 65) and black
What were the conclusions of the article?
- women and men had differing access
- low proportions of both men and women met the recommended benchmarks for timeliness of procedures
- women with anxiety and men and women with no chest pain and traditional risk factors and with feminine gender identity were at increased risk for poor access to care.
