All teaching innovations need to be tested in order to validate academic outcomes and benefits. Assess and evaluate the course in order to provide justification and to demonstrate academic rigor for online instruction, gather objective data such as scores on exams 

Educators/instructors should use student/course evaluations, but that should not be the only measure of course success. Instructors should review students' posts and assessment measures to see if what was accomplished was what was intended.

 Which method is best for providing an online course – synchronous or asynchronous learning?

It depends. There are advantages and disadvantages to both types of learning. Each method should be investigated to see what works best for your particular course.

Do guidelines enhance the synchronous and asynchronous delivery process?