Initial data on a 5-item measure of OCD symptom severity and change: The obsessive compulsive session change index (OCSCI)

• The OCSCI is a brief measure of OCD severity and change.
• The first 4 items measure severity and interference of obsessions and compulsions.
• A fifth item measures change in OCD symptoms since before treatment.
• OCSCI-severity and change items demonstrated good psychometric properties.
• The OCSCI can be useful as a measure of client progress throughout treatment.

Repeated measurement of symptoms throughout treatment allows providers to assess individual patterns of symptom change. However, outside of a clinical trial, administration of lengthy measures at each session is unlikely. Therefore, in order to bridge the gap between clinical research and actual clinical practice we developed a brief self-report measure of obsessive compulsive symptoms that can be used at each session, the Obsessive Compulsive Session Change Index (OCSCI). The OCSCI assesses time spent on obsessions, time spent on compulsions, interference and distress related to obsessions and compulsions, and relative change in symptoms from the beginning of treatment. This paper reports initial psychometric properties of the OCSCI. Twenty-seven adults receiving exposure and ritual prevention for obsessive compulsive disorder (OCD) completed the OCSCI at each session. Results showed that the OCSCI had good internal consistency, and convergent and divergent validity. Specifically, the OCSCI had moderate to strong correlations with both self-reported and clinician rated OCD. Finally, the OCSCI was not as strongly correlated with depressive symptoms as it was with OCD symptoms. The findings presented herein suggest that the OCSCI can be useful as a measure of client progress throughout treatment.