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Question 3#

In a non-randomised controlled study evaluating the hypothesis that laparoscopic nephrectomy, as compared with open nephrectomy, reduces the length of hospital stay; the null hypothesis was inappropriately accepted. This is known as?

a. Type I error
b. False positive error
c. Power of a study
d. Publication bias
e. Type II error

Correct Answer is E

Comment:

Answer E

A type I error (or false positive error) is said to have occurred when a null hypothesis, which is true, is inappropriately rejected. The probability of making a type I error is equal to the chosen significance level (p-value). Conversely, when a null hypothesis, which is false, fails to be rejected, a type II error (or false negative error) is said to have occurred. The probability of not making a type II error equals the power of the test. Publication bias is not related to hypothesis testing and statistical error.