Chapter 3 Flashcards
Purpose
-be able to identify independent and dependent variables
-Be able to describe independent and dependent variable
Importance
The independent variable is typically the risk factor that influences the dependent outcome variable
Practical application
we typically manipulate the independent variable to influence the dependent variable
Independent Variable
-what is being manipulated
-influences the dependent variable
-cause (independent variable) and effect (dependent variable)
Depenedent Variable
-not manipulated
-the outcome variable
-is “dependent” on the independent variable
Blind study
subject
Double blind study
subject + investigators (admin treatment)
Triple blind study
subject + investigators + person assessing outcome
Placebo (sham)
Any therapeutic procedure (or a component of any therapeutic procedure) which is given
1. deliberately to have an effect or
2. unknowingly and has an effect on a symptom, syndrome disease or patient but which is objectively without specific activity for the condition being treated
Placebo effect
definced as the changes produced by placebos
Placebo (Paul’s definition)
Intervention that should not matter that has a positive outcome
Hawthorne effect
Individuals modify as aspect of their behaviors because they know they are being observed
Mechanism of action -placebo
Psychological: expectations via “verbal cues as modulators of expectancies”
Nocebo
-negative expectation
-when subject knows that they were randomized into the “control” group
Descriptive Studies
Describes the occurrence of a disease in a population, answers the who, where, when to explain
Analytical studies
analyzing the relationships between health status and dieases
Best studies are….
RCT (Randomized control trials)
Experimental
a active attempt to change a determinant; involving an intervention
Observational
participants are monitored for change; with or without a specific intervention
Cohort
group of participants studied/followed as a whole
Analytical
determining casual relationships
Field
trial- study occurs outside the lab
Community Trial
studied population is an entire community
Multifactorial
studying the effect of 2 unrelated interventions at the same time in the same group
Longitudinal
occurring over a very long time period
Incidence
of new cases / # persons at risk
Un-ethical
to expose or force independent variable
Quasi-experimental, semi-experimental, and convenice sample
were not random studies
Odd ratio is what type of study?
Retrospective study
Odds
proportion
Probability
rate
