Tests of Significance — t, chi-square

A hospital in Mumbai conducted a study to compare the mean systolic blood pressure reduction (in mmHg) following two antihypertensive regimens. Group A (n=25) received atenolol monotherapy with mean reduction of 18 mmHg (SD=6 mmHg), while Group B (n=25) received atenolol plus amlodipine with mean reduction of 24 mmHg (SD=7 mmHg). Both groups were independent, and the data were normally distributed. The researcher wants to test if the combination therapy produces significantly greater blood pressure reduction. What is the appropriate test and the most likely outcome at p<0.05?

In a cross-sectional study of 500 Indian factory workers, researchers compared the prevalence of occupational asthma between two exposure groups using a 2×2 contingency table. The chi-square test yielded χ² = 8.64 with 1 degree of freedom. Which of the following statements is most accurate regarding the interpretation of this test result?

A clinical trial in Mumbai compares the mean systolic blood pressure (mmHg) between two treatment groups: Group A (n=45, receiving Drug X) and Group B (n=48, receiving Drug Y). Both groups are normally distributed with similar variances. The investigator wishes to test whether the mean SBP differs significantly between the two groups. Which test should be used?

In a study comparing the effectiveness of two malaria treatment regimens in rural India, researchers used chi-square test to analyze categorical outcomes. All of the following are correct regarding the chi-square test EXCEPT:

When comparing the distribution of a categorical variable across two independent groups, which test is most appropriate?