Bioequivalence and Bioavailability Forum

Dear All

Can give the reference or suggession on below question:

Different CROs are using different screening period critera like---- subjects will be screened 22/28 days prior to IP administration.

Why people are using different criteria?

As per my experiance - If the screening period is short than chances of rejection of subjects is less in enrollment of study (on medical ground).

If i m right than why people are using different criteria?

Is there any guideline or reference suggesting the criteria?

Waiting for reply.

Thanks in advance

Virendra Patel