Question

A group of inexperienced weightlifters was randomized to either perform Crossfit or Olympic lifting workouts for 10 weeks. We then determined whether or not each participant increased their one repetition maximum (1RM) by more or less than 15%. What statistical test should be used to determine if the proportion of participants that increased their 1RM by more than 15% is higher in those performing Crossfit or Olympic lifting?

Answer 1

The appropriate hypothesis test for this question is the two proportions test. As the name implies, it is often used to compare existing percentages between two groups. The raw data behind the percentages must be available as the sample size becomes crucially important in determining the test statistics.

The test statistic of the two-proportion test is the Z value. When the sample becomes very large, the Z value is governed under a normal function and is commonly known as the standardized Z value