A hospital research committee is reviewing several proposed clinical trial protocols. Match each proposed clinical study design with the most appropriate statistical test to analyze its primary data.
- Comparing the mean reduction in systolic blood pressure between two independent groups of hypertensive patients (data is continuous and normally distributed).Two-sample (independent) t-test
- Evaluating the incidence of 30-day readmission (yes/no) across three different post-discharge care models in a cohort of heart failure patients.Chi-square test
- Comparing the median duration of mechanical ventilation (highly skewed continuous data) among patients randomized to three different sedation protocols.Kruskal-Wallis test
- Analyzing the pre-intervention and post-intervention differences in pain scores (ordinal data) in a single group of osteoarthritis patients.Wilcoxon signed-rank test
Answer
Study 1 matches with Two-sample (independent) t-test; Study 2 matches with Chi-square test; Study 3 matches with Kruskal-Wallis test; Study 4 matches with Wilcoxon signed-rank test.
Each study design requires a specific statistical test based on the variable types and data distribution. Normal continuous data across two independent groups uses a two-sample t-test. Categorical data across groups uses a Chi-square test. Skewed continuous data across three or more groups requires the Kruskal-Wallis test. Paired ordinal data requires the Wilcoxon signed-rank test.
Step-by-Step Solution
Key Concept
Selection of the appropriate inferential statistical test depends on the variable type (categorical, continuous, ordinal), the data distribution (normal vs. skewed), and the study design (number of groups and whether they are independent or paired).
Estimated Time:1m 30s