When to Use Which t-test?

Research Topic: The Effect of Phonics Instruction on English Pronunciation Accuracy in Primary School Students

1. There is one group of 30 primary students. The group will be measured twice: once before the phonics instructions and once after the phonics instructions. 
2. The data will be collected from the same participants at two different times
3. Pair-simple t-test is the most appropriate statistical test in this case study because it enables researchers to compare 2 mean scores under 2 different situations.