More information on overactive bladder from these trusted medical institutions:
American Urological Association (AUA) - Patient's Guide to Overactive Bladder
Mayo Clinic 
Cleveland Clinic
University of California San Francisco
Kaiser Permanente 

For providers:
American Urological Association (AUA) and Society of Urodynamics, Female Pelvic Medicine, and Urogenital Reconstruction (SUFU) - Diagnosis and Treatment Guidelines 2014.