Objective: To explore critically whether there is a robust basis for the concept of an obsessive-compulsive (OC) spectrum of disorders, and if so, which disorders should be included.
Method: Selective literature review concentrating on three proposed members of the OC spectrum, namely body dysmorphic disorder, hypochondriasis and trichotillomania.
Results: Obsessive-compulsive disorder (OCD) itself is a heterogeneous condition or group of conditions, and this needs to be appreciated in any articulation of a 'spectrum' of OC disorders. The basis for 'membership' of the spectrum is inconsistent and varied, with varying level of support for inclusion in the putative spectrum.
Conclusion: A more fruitful approach may be to consider behaviours and dimensions in OCD and OC spectrum disorders, and that this should be encompassed in further developments of the OC spectrum model.