STP Research Methods 4 — Questions and Answers
Question 1: Which qualitative research method involves the researcher becoming immersed in a community to observe behavior in its natural context?
- Focus groups
- Ethnography (Correct answer)
- Grounded theory
- Thematic analysis
Correct answer: Ethnography
Ethnography involves prolonged, immersive observation within a community or setting to understand cultural practices and behaviors in context.
Question 2: Sensitivity of a diagnostic test refers to its ability to:
- Correctly identify those who do NOT have the disease
- Correctly identify those who DO have the disease (Correct answer)
- Minimize the proportion of false positives
- Produce consistent results on retesting
Correct answer: Correctly identify those who DO have the disease
Sensitivity is the proportion of true positives correctly identified by the test — its ability to detect those who have the disease.
Question 3: In a systematic review, heterogeneity among included studies refers to:
- The use of different statistical software across studies
- Variation in results beyond what would be expected by chance (Correct answer)
- Differences in publication dates of included studies
- The presence of unpublished studies
Correct answer: Variation in results beyond what would be expected by chance
Heterogeneity describes variability in study results that exceeds chance, often assessed using the I² statistic, and affects whether results can be pooled.
Question 4: Which research design is most suitable for studying a rare disease with a long latency period?
- Randomized controlled trial
- Cross-sectional study
- Case-control study (Correct answer)
- Ecological study
Correct answer: Case-control study
Case-control studies work backwards from outcomes to exposures, making them efficient for rare diseases since cases are identified first and the long latency is already expressed.
Question 5: The intraclass correlation coefficient (ICC) is used to assess:
- The association between two continuous variables
- Agreement between two or more raters measuring the same subjects (Correct answer)
- The strength of a diagnostic test
- The ratio of explained to unexplained variance
Correct answer: Agreement between two or more raters measuring the same subjects
ICC measures the degree of agreement or consistency between two or more raters or repeated measurements of the same continuous variable.
Question 6: Publication bias in a systematic review most often results in:
- Overestimation of treatment effects because positive studies are more likely to be published (Correct answer)
- Underestimation of treatment effects because large studies dominate
- Greater heterogeneity among included studies
- More accurate effect estimates due to larger sample sizes
Correct answer: Overestimation of treatment effects because positive studies are more likely to be published
Publication bias inflates effect estimates in systematic reviews because studies with positive or significant results are disproportionately published.
Question 7: A power calculation is conducted before a study primarily to:
- Determine the significance threshold for the primary outcome
- Estimate the minimum sample size needed to detect a clinically meaningful effect (Correct answer)
- Calculate the expected confidence interval width
- Decide which statistical test to apply to the data
Correct answer: Estimate the minimum sample size needed to detect a clinically meaningful effect
Power calculations determine the sample size required to have a specified probability (typically 80%) of detecting a true effect of a given size.
STP Research Methods 4
Which qualitative research method involves the researcher becoming immersed in a community to observe behavior in its natural context?