Time interval between the onset of symptoms and diagnosis of multiple sclerosis and the influential factors: A national registry-based study.

Objective: The time to diagnosis of multiple sclerosis (MS) is of great importance for early treatment, thereby reducing the disability and burden of the disease. The purpose of this study was to determine the time from the onset of clinical symptoms to the diagnosis of MS and to evaluate the factors associated with a late diagnosis in Iranian MS patients.

Methods: The present cross-sectional study was conducted on patients with MS who were registered in the National MS Registry System of Iran (NMSRI).