The purpose of the study is to assess patient's persistency in maintaining solifenacin treatment for overactive bladder.

Inclusion Criteria:

• Overactive bladder symptoms lasting for more than 3 months
• The question 3 score of the overactive bladder symptom score(OABSS)≥ 2 and the sum score of OABSS ≥ 3
• Symptoms of urinary urgency defined as a level of 1 to 2 in a 3-point Urgency Perception Scale (UPS)

Exclusion Criteria:

• Any condition that would contraindicate their usage of anticholinergic treatment, including: urinary retention, gastric retention, uncontrolled narrow angle glaucoma, myasthenia gravis
• Symptomatic acute urinary tract infection (UTI)
• Diagnosed or suspected of interstitial cystitis
• Treatment with anticholinergic drugs for over 3 months within 12 months prior to the study
• Pregnant or nursing women
• Treatment within the 14 days before the study or expected to initiate treatment during the study with any anticholinergic drugs other than solifenacin or treatment for overactive bladder with other drugs
• Any other condition which, in the opinion of the investigator, makes the patient unsuitable for inclusion

OAB patients who were treated with solifenacin