Differential diagnosis of obsessive-compulsive symptoms from delusions in schizophrenia: A phenomenological approach

Table 1 Clinical features of obsessions/compulsions versus delusions/delusional repetitive behaviours

Clinical features	Obsessions/compulsions	Delusions/delusional repetitive behaviours
Source of origin and sense of ownership of the thought(s)	Internal origin, assumed ownership	Internal origin, assumed ownership (with the exception of passivity-experiences of thought- insertion)
Conviction	Absent, though patient fears that they might come true	Absolute
Consistency with one’s belief- system	Inconsistent	Integrated into patients’ belief-system
Awareness of inaccuracy	Recognized as excessive and unreasonable to hold	Recognized as totally justified or even as self-evident
Awareness of their symptomatic nature	Very strong or at least medium strong	Virtually absent
Resistance	Very strong though unsuccessful	None
Emotional impact	Experience of marked distress/anxiety as a joint effect of obsessions’ intrusiveness, doubts that their contents may come true along with the failure to resist them successfully	Possible experience of distress and anxiety as an effect of one’s conviction about incurred imminent dangers
Aim of repetitive behaviours	Temporary neutralization of intrusive thoughts, images or impulses	Harmonization of behaviour with delusional beliefs
Awareness of their inappropriateness	Recognized as inappropriate, excessive and unreasonable	Recognized as appropriate and even reasonable, given their motivating delusional beliefs
Awareness of their symptomatic nature	Strong	Virtually absent
Immediate effect of repetitive behaviours on thoughts	Behaviours make thoughts temporarily less intrusive	Behaviours per se do not affect underlying delusional beliefs
Emotional impact of repetitive behaviours	Temporarily distress-reducing, but eventually sources of further distress/anxiety	Behaviours per se do not affect level of distress or anxiety