basic concepts and research design issues

Question 1

What are the three general classes of research studies? Of these, which is necessary for
establishing causation?

Answer 1

1)descriptive
2)experimental
3)correlational

to establish causation we need the experimental

Question 2

Observational epidemiological studies may provide important information regarding the association
between variables and for providing temporal sequence evidence. What is the problem in attempting
to modify individual behavior based on observational epidemiological studies?

Answer 2

although epidemiological studies can give us information regarding the population as a whole, one must devise a plan to alter their behavior based on their own characteristics and individual personality.

Question 3

Randomized controlled trials (RCTs), which are often considered the gold standard to determine the
risk or benefit of a particular intervention, require three design conditions. What are these?

Answer 3

Randomized assignment
control group
manipulate variable

Question 4

. Meta-analytic reviews are vital for establishing the necessary data to meet causation. What is a
meta-analysis and how is it different from a more traditional narrative review? What is the
statistic that is often used in meta-analysis?

Answer 4

a meta-analysis takes multiple studies then analyzes the outcomes of each study. From the conclusions of every study, we observe how different the control groups are from the experimental, this is our effect size. a statistic often used in meta- analysis is the P value which is essentially how significant the data is.

Question 5

List and
describe Hill’s Criteria for Establishing Causation.

Answer 5

strength of association (effect size)
consistency (reproducibility)
specificity
temporal sequence(which came first)
biological gradient (dose-response)
plausibility (mechanisms)
coherence (between epidemiological and laboratory findings)
experimental evidence