In this task, you are given a multiple-choice question about healthcare. Answer the question based on your information and classify your answers into '1', '2', '3', and '4'.
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Question: Question: When comparing the characteristics of pragmatic or confirmatory clinical studies with explanatory or exploratory clinical studies, which of the following is an advantage of the former? 
 Options:  <1> Information about subgroups of patients representative of the usual clinical practice. <2> Very homogeneous sample, with little variability. <3> Greater capacity to detect differences in the effectiveness of interventions. <4> Greater internal validity <5> Smaller sample size

Answer: 1


Question: Question: If after establishing the confidence interval with respect to a difference between two independent means, we find that the zero value is not in the interval: 
 Options:  <1> We can not make any decision regarding the null hypothesis of equality of means. <2> We can not reject the null hypothesis of equality between population means. <3> We must reject the null hypothesis of equality between population means. <4> We accept the null hypothesis of equality between the population means. <5> We reject the alternative hypothesis of equality between population means.

Answer: 3


Question: Question: The second heart sound coincides with: 
 Options:  <1> End of ventricular diastole. <2> End of atrial diastole. <3> Opening of the aortic valve. <4> Atrial systole <5> Closing of the semilunar valves.

Answer:
5