1. Department of Neurology; National Neuroscience Centre; Kolkata India
2. Department of Statistics; Ballygunje Science College; University of Calcutta; Kolkata India
3. Department of Neurology; BIN and IPGME&R; Kolkata India
4. Department of Psychiatry; Medical College Kolkata; Kolkata India
5. Department of Pharmacology; IPGME&R; Kolkata India
6. Sampling Unit; Indian Statistical Institute; Kolkata India