“…However, our sample size compares to earlier samples in the ERP field, which used GTS patients samples at n=6 (Van de Wetering et al, 1985), n=10 (Johannes et al, 2001a(Johannes et al, ,b, 2003, n=12 (Johannes et al, 1997) and n=24 (van Woerkom et al, 1994). The same applies with ERP studies of OCD patients with various sample sizes from a n=8 (Di Russo et al, 2000), n=9 (Gehring et al, 2000), n=13 (Morault et al, 1997), n=15 (Sanz et al, 2001) and n=21 (Morault et al, 1998). Future research would ideally recruit larger samples and compare GTS+OCS with other comorbid groups such as highly anxious, depressive or hyperactive GTS patients.…”