CED Research Methods & Evidence-Based Practice 2 — Questions and Answers
Question 1: In emergency dispatch research, what does a 'cohort study' involve?
- Randomly assigning dispatchers to different protocols
- Following a group of subjects over time to observe outcomes (Correct answer)
- Reviewing historical incident reports retroactively
- Surveying dispatchers about their protocol preferences
Correct answer: Following a group of subjects over time to observe outcomes
A cohort study follows a defined group prospectively over time to observe outcomes related to exposures or interventions.
Question 2: Which statistical measure indicates how much individual data points deviate from the mean in dispatch response time analysis?
- Median
- Mode
- Standard deviation (Correct answer)
- Range only
Correct answer: Standard deviation
Standard deviation quantifies the spread of data points around the mean, indicating variability in response times.
Question 3: What is 'informed consent' in the context of research involving emergency dispatchers?
- Supervisors approving a research study design
- Participants voluntarily agreeing after being fully informed of risks and benefits (Correct answer)
- IRB certification of the research protocol
- Dispatch center legal clearance for data use
Correct answer: Participants voluntarily agreeing after being fully informed of risks and benefits
Informed consent requires participants to voluntarily agree to participate after receiving complete information about the study.
Question 4: A dispatch center wants to evaluate whether a new CPR instruction script improves caller compliance. Which study design is most rigorous?
- Case report
- Randomized controlled trial (Correct answer)
- Cross-sectional survey
- Expert opinion review
Correct answer: Randomized controlled trial
A randomized controlled trial minimizes bias by randomly allocating participants to treatment or control groups, providing the strongest causal evidence.
Question 5: What is 'selection bias' in emergency dispatch research?
- Choosing only favorable data points for analysis
- Systematic differences between study groups due to non-random selection (Correct answer)
- Preferring quantitative over qualitative methods
- Excluding outliers from statistical analysis
Correct answer: Systematic differences between study groups due to non-random selection
Selection bias occurs when the method of selecting participants creates systematic differences that distort study results.
Question 6: Which level of evidence is considered LOWEST on the evidence hierarchy?
- Systematic review
- Randomized controlled trial
- Cohort study
- Expert opinion or anecdotal evidence (Correct answer)
Correct answer: Expert opinion or anecdotal evidence
Expert opinion and anecdotal evidence sit at the bottom of the evidence hierarchy because they lack systematic methodology and are most prone to bias.
Question 7: What does 'inter-rater reliability' measure in dispatch protocol research?
- Consistency of a single rater across multiple evaluations
- Agreement between two or more independent raters scoring the same data (Correct answer)
- The accuracy of dispatch software scoring algorithms
- Correlation between protocol compliance and patient outcomes
Correct answer: Agreement between two or more independent raters scoring the same data
Inter-rater reliability assesses the degree to which different raters produce consistent results when evaluating the same subject or data.
CED Research Methods & Evidence-Based Practice 2
In emergency dispatch research, what does a 'cohort study' involve?