Module 2 Flashcards
(41 cards)
Incidence
Number of new cases of disease that develop in an at risk population during a specified period of time, measured as a rate
Prevalence
Number of cases of a disease out of total population during a period of time, measured as a proportion
2 x 2 table
Categorizes people based on disease and expose your status. Two columns are disease and not disease, two rows are exposed and not exposed
Health equity
The attainment of the highest level of health for all people. Relates to things that are controllable
social determinants of health examples
Socio economic status, housing, transportation, education, Access to medical care
Context as related to study design
What or who the study is about, the population or who is represented by the Study
If not considered, could create a study that is unethical such as for people that cannot afford a particular treatment. Another issue could be the study could be conducted in an area where a particular disease is not relevant
Review or meta-analysis
Synthesizing existing. Knowledge
Case series
Describe a group of individuals with a disease
Experimental study or randomized controlled trial
Compare outcomes in participants assigned to an intervention and control group
Qualitative study
Seek to understand how individuals and communities perceive and make sense of the works and their experiences
Retrospective Study cohort
Starting a study with people that already have a disease or condition and looking to the past for data and exposure history, we can learn what exposures may be related to a disease
Good if disease has long induction in latency., A historical exposure, and less expensive and less time than a prospective
Prospective Study cohort
Following study participants into the future, can learn about the latency. And progression of disease as well as Time of death
Good if disease has short induction in latency. And a current exposure, high-quality data
Population for a study, outer circle to inner circle
Starting with outer circle
- Target population, the general population that the study seeks to understand
- Source population, the specific individuals from which a representative sample will be drawn
- Sample population, individuals asked to participate
- Study population, eligible participants
Ecological study
Examine relationship between exposure and disease with population level data rather than individual level data. Studies groups that are usually defined by place, time or a combination of the two.
Pros are low cost and wide range of exposure level
Cons are ecological fallacy and confounding variable’s
Cross-sectional studies
Relationship between disease and current exposure level in a defined population at Single point in time . A snapshot. Often used for public health planning and work place settings
Pros are generalizable and low-cost
Cons are cannot infer what came first, the exposure or the disease? And these studies usually identify those who have the disease for a long duration, because those who quickly die or a cover or not likely to be identified
Ecological fallacy
The assumption that results of an ecological study can be used to make conclusions on the individual basis
We cannot’s necessarily infer a relationship observed on the group level to the individual level
Case control study
Compare exposure history is in people with disease, cases, and people without diseases, controls.
Use 2 x 2 table for this and odds ratio
Incidence in exposed / incidence in unexposed
Good if a little is known about disease, can evaluate many exposures, good if it disease is rare and has long induction and latency., Good if exposure data is expensive and underline population is dynamic
Cohort study
Compare rates of new, incident, disease in people with different exposure histories or follow the population forward in time to look for incident diseases
Cons are expensive and lost to follow up
Good if Little is known about exposure, can evaluate many effects of exposure, good if exposure is rare, and underlying population is fixed
Observational
Studies causes, prevention, and treatments for diseases. Investigator passively observes as nature takes it’s course
Experimental
Studies preventions and treatments for disease. Investigator actively manipulates which group receives the agent understudy
Experimental study
Used to learn about a prevention or treatment method.
Pros, they are high in validity and use of randomization controls for confounding. Good for studying a small effect.
Cons are ethical concerns and cost
Observational studies
Cohort, case control
Can study a wider range of exposures, preventions, treatments, and possible causes of disease compared to Experimental. Provide information to explain causes of disease incidence, determinants of disease progression, predict future healthcare needs a population, control disease.
Pros are can be done if trial is not ethical or expensive, good if moderate or large a fact is expected
Cons are investigator is unable to have control over influences or external factors
Internal validity of a study
How true the experiment is for the target population. Internal validity must be established before the study results can be generalized to populations be on the study subjects, if it is invalid it cannot be generalized to any population
External validity
How will the results of the study can be applied to people outside of the study, it’s generalizability
