Obsessive-compulsive and related disorders (OCD)Disorders in this chapter — each on a separate page: 6B20 Obsessive-compulsive disorder (OCD) 6B21 Dysmorphic disorder (BDD) 6B22 Olfactory reference disorder (ORS) 6B23 Hypochondriasis 6B24 Hoarding disorder 6B25 Body-focused repetitive behaviour disorders