“…Comorbidity is the rule rather than the exception, with major depressive disorder (MDD) being one of the most frequent comorbid diagnoses (Lochner et al, 2014;Klein Hofmeijer-Sevink et al, 2013). Comorbidity rates differ largely due to methodological differences, but overall approximately one third of the patients with OCD suffer from a current comorbid MDD, and about twothird have lifetime comorbidity of MDD (Viswanath et al, 2012;Quarantini et al, 2011;Torres et al, 2006;Pinto et al, 2006;LaSalle et al, 2004). Moreover, many OCD patients suffer from depressive symptoms, but do not fulfill the diagnostic criteria for a depressive episode.…”