CPT Research Methods & Evidence-Based Practice 3 — Questions and Answers
Question 1: A tutor selects only students from their own caseload for a study on study skills. This sampling method is called:
- Stratified random sampling
- Cluster sampling
- Convenience sampling (Correct answer)
- Systematic sampling
Correct answer: Convenience sampling
Convenience sampling selects participants who are readily available, which may limit generalizability.
Question 2: Which statistical measure is most resistant to the influence of extreme outliers in a dataset?
- Mean
- Standard deviation
- Median (Correct answer)
- Range
Correct answer: Median
The median is the middle value in a ranked dataset and is not mathematically affected by extreme scores the way the mean is.
Question 3: A tutor implements a new math strategy and tracks one student's performance daily using baseline and intervention phases. This is an example of:
- Group experimental design
- Single-subject research design (Correct answer)
- Correlational research
- Ethnographic research
Correct answer: Single-subject research design
Single-subject (or single-case) research design tracks one individual across baseline and treatment phases to evaluate intervention effects.
Question 4: Which of the following best describes a p-value of 0.03 in a tutoring intervention study?
- There is a 3% chance the intervention works
- There is a 97% probability the null hypothesis is true
- There is a 3% chance of obtaining results at least this extreme if the null hypothesis were true (Correct answer)
- The effect size is 3%
Correct answer: There is a 3% chance of obtaining results at least this extreme if the null hypothesis were true
A p-value represents the probability of observing results as extreme as those found, assuming the null hypothesis is true.
Question 5: A tutor reads a study where the researcher knew which students received the intervention when measuring outcomes. This introduces:
- Demand characteristics
- Observer bias (Correct answer)
- Regression to the mean
- Attrition bias
Correct answer: Observer bias
Observer bias occurs when the evaluator's knowledge of group assignment influences how they measure or rate outcomes.
Question 6: Which research approach is most appropriate for exploring how a student personally experiences learning difficulties?
- Double-blind randomized trial
- Phenomological qualitative research (Correct answer)
- Time-series analysis
- Regression analysis
Correct answer: Phenomological qualitative research
Phenomenological qualitative research explores individuals' lived experiences in depth, making it suitable for understanding personal learning challenges.
Question 7: An effect size of d = 0.8 in a tutoring study is typically interpreted as:
- Small effect
- Medium effect
- Large effect (Correct answer)
- Negligible effect
Correct answer: Large effect
By Cohen's conventions, d = 0.2 is small, d = 0.5 is medium, and d = 0.8 or greater is considered a large effect.
CPT Research Methods & Evidence-Based Practice 3
A tutor selects only students from their own caseload for a study on study skills.
This sampling method is called: