Types of Clinical Epidemiological Studies Quiz

14 Questions

What is the purpose of experimental/intervention studies?

To do something to the patient and observe what happens

Which type of evidence is considered at the top of the 'Nutrition Hierarchy of Evidence'?

N-of-1 studies

What is the purpose of whole systems research?

To understand traditional/historical use

Which type of evidence is considered as one of the basic types of clinical epidemiological studies?

Cohort studies

What type of study design is best for confirming cause/effect?

Randomized controlled trial (RCT)

Which type of study design compares prior exposure and current disease status in Diseased and Non-Diseased groups?

Case-control study

Which type of study design assesses entire systems of care instead of individual treatments and modalities?

Whole practice/systems research

What kind of intervention study allows people to choose between different arms, like cancer survivors choosing between MBT or Tai Chi?

Preference study

Does a maternal diet deficient in B12 impact fetal brain development? What would be an appropriate study design?

Clinical trial

Time cohort study compares incidence between which groups?

Exposed and Un-exposed groups

What is a limitation of Case-control studies?

They are subject to recall bias.

What is the purpose of a N of 1 study?

To compare the self while taking the real treatment vs taking the comparison.

What is the purpose of preclinical studies?

To study pharmacokinetics and mechanisms of action.

What does narrative review aim to do?

To summarize research findings.

Study Notes

Treatment TIME RANDOMIZED CONTROLLED TRIAL (RCT) Characteristics: Defined population (inclusion/exclusion criteria), 2(+) groups: Treatment arm and Comparison arm, Prospective design (looks forward in time), randomized (equal chance of being assigned to intervention or control group), may include Blinding (minimizes expectation effect), and is the best design for confirming cause/effect.
Other kinds of intervention studies exist, such as:
- Cross-over (everyone gets intervention and comparison),
- Preference (controlled, not randomized), allowing people to choose between different arms (like cancer survivors choosing between MBT or Tai Chi),
- Open-label, Pre/Post (everyone gets the intervention, but they know it and assess changes before and after).
A clinical question is posed: "Does a maternal diet deficient in B12 impact fetal brain development?"
An appropriate study design would be a "Clinical trial" (controlled experiment).
Observational studies ask if there is a relationship between a risk factor and an outcome (harm or benefit), such as high intake of blueberries and a lower risk of cancer.
Time-based observational studies include:
- Time cohort study (compare incidence between Exposed and Un-exposed groups).
- Cross-sectional study (compare prior exposure and current disease status in Diseased and Non-Diseased groups).
- Case-control study (compare current disease status and current exposure).
These studies have strengths and weaknesses:
- Case-control and cross-sectional studies are faster and less expensive.
- Case-control studies can look at rare outcomes, but they are subject to recall bias.
- Cross-sectional studies assess exposure and outcome at one time point and are less expensive, but they cannot establish causality.
Other study designs include:
- Case reports and case series (report previously undocumented events, but they are subject to bias and generalizability).
- N of 1 study (individualized RCT, comparing the self while taking the real treatment vs taking the comparison).
- Preclinical studies (in vitro and in vivo, without human or animal subjects, used to study pharmacokinetics and mechanisms of action).
Synthesis research (narrative and systematic review) is used to draw bigger conclusions based on individual studies.
Whole practice research is essential to understand how the results of RCTs apply to real clinical practice of naturopathic medicine.
Whole practice/systems research assesses entire systems of care instead of individual treatments and modalities.
WSR trial design is used to study what is actually done in the real world, and it is a modified RCT design using an entire system of medicine instead of individual therapy.