CET Research Methods & Evidence-Based Practice 2

Question 1

In a randomized controlled trial evaluating a new echocardiographic protocol, which element is MOST critical for minimizing selection bias?

Accepted Answer

Random allocation of participants to groups

Answer

Random allocation ensures that known and unknown confounders are evenly distributed between groups, directly minimizing selection bias.

Question 2

A meta-analysis of studies on diastolic dysfunction grading reports high statistical heterogeneity (I²=85%). What does this indicate?

Accepted Answer

There is significant variability in results across studies

Answer

An I² of 85% indicates substantial heterogeneity, meaning the variability in study results is greater than expected by chance alone.

Question 3

Which study design is BEST suited to determine the incidence of new-onset atrial fibrillation detected by echocardiography in a healthy population over 10 years?

Accepted Answer

Prospective cohort study

Answer

A prospective cohort study follows a disease-free population over time, making it ideal for measuring incidence of new conditions.

Question 4

When applying evidence-based practice, a CET finds a Level I systematic review and a Level III expert opinion supporting different LVEF measurement techniques. Which should guide practice?

Accepted Answer

The systematic review, as it represents the highest level of evidence

Answer

Level I systematic reviews sit at the top of the evidence hierarchy and should take precedence over expert opinion in guiding clinical practice.

Question 5

A study reports that 3D echocardiography has a sensitivity of 92% and specificity of 88% for detecting apical thrombus. What does specificity of 88% mean?

Accepted Answer

88% of patients without thrombus were correctly identified as negative

Answer

Specificity is the ability of a test to correctly identify true negatives — patients who do not have the condition.

(CET) Certified Echocardiography Technician Practice Test

(CET) Certified Echocardiography Technician Practice Test

CET Research Methods & Evidence-Based Practice 2