Study Designs Flashcards
“research”
a rigorous and systematic investigation of any phenomenon
rigorous
refers to quality of research - using appropriate methods and analytical techniques
systematic
refers to the practice of conducting a research in a logical and orderly, disciplined manner
Types of Study designs (8)
- ecological/correlation
- cross-sectional survey
- cohort study
- case-control study
- RCT
- clinical trial
- animal study
- systematic review or meta-analysis
Descriptive/Exploratory Designs
- collected to ID potential associations
- useful to make recommendations for future research
- collect baseline data
- useful in developing hypothesis
Nutritional Epidemiology
the study of the effect of nutrition on disease
⇒ ecological, case control, cohert
Ecological/Correlation
- observation of a group of people usually within 1 geographical region and loo at diet with some outcome
- or compare a factor of interest among different groups and the estimates of the intake of food/nutrients for those groups
Correlation strengths
- used as an exploratory tool
- yielded considerable knowledge about dietary factors and chronic diseases
- used to generate hypothesis
Hard to establish causality
- most chronic diseases are multifactoral
- chronic diseases have long latency periods/ when do they start
- hard to accurately estimate intake
- multiple confounding factors
Cross sectional Surveys
- a snap shot of an entity
- association between an indicator of nutrition and a health characteristic measured at the same time
strengths of Cross sectional surveys
- snap shot of entire region
- used to ID factors that may affect the level of risk factor
- generates hypothesis
Case Studies
- collect info on one or a few individuals
- collect comprehensive information about a cluster of characteristics
- usually do not manipulate the environment
- findings are very specific to the group you selected
Surveys
- used to collect information on a larger group of individuals
- can be researcher or self-administered
- cross sectional surveys collected info at one point in time
longitudinal surveys look at the issue over time
Analytical Designs
exploratory/epidemiological ⇒ case control studies, cohort studies (next)
Explanatory - test ⇒ clinical trials, animal studies
Case Control Studies (retrospective)
- a group of subjects with the disease is compared with a group without the disease and their exposure history is compared
- collect retrospective info on diet and lifestyle