Pre and post module self-assessments

Hi, 

I need to incorporate pre and post module self assessments using a Likert scale so we can measure the impact of content on learner's knowledge. However, I need to incorporate these into existing modules that already have learning checks, of which the scores are recorded and indicate to the LMS if they have completed and therefore passed the module. 

This is urgent and many of our modules require this and I have no idea how to implement this! Please help!