When is a critical region necessary for hypothesis testing?

[EdwardH115]

I've recently been taught binomial hypothesis testing and my teacher has always said to construct a critical region then check if the value lies within. But when I've done practice questions, most of the mark schemes don't use a critical region, they just test the specified value and check if it above/below the significance level. Am I unnecessarily creating a critical region or is it good practice?

 

[BigBeachBanana]

I've recently been taught binomial hypothesis testing and my teacher has always said to construct a critical region then check if the value lies within. But when I've done practice questions, most of the mark schemes don't use a critical region, they just test the specified value and check if it above/below the significance level. Am I unnecessarily creating a critical region or is it good practice?

Constructing a critical region provides a more visual representation of the hypothesis testing process compared to directly comparing p-values with the significance level. Both approaches are valid and yield the same conclusion.