Purpose of the DOCS

There are a number of measures available for assessing OCD symptoms. The DOCS was developed to address a number of drawbacks of the most popular scales such as the Yale-Brown Obsessive Compulsive Scale (YBOCS), the Obsessive Compulsive Inventory (OCI and OCI-R) and the Padua Inventory (PI and PI-R). These drawbacks include:

1) Because items on many OCD measures (e.g., OCI-R, PI) assess only the most common (or quintessential) OCD symptoms, patients with these types of symptoms will receive higher scores than equally affected patients with other (less common) types of symptoms.

2) Most self-report OCD scales contain a one-dimensional assessment of severity. For example on the OCI-R, respondents rate their level of “distress” associated with their obsessions and compulsions. Research, however, shows that OCD symptom severity is multidimensional, consisting of parameters such as distress, functional interference, and the frequency or duration of obsessions and compulsions.

3) Many OCD symptom measures assess obsessions separately from compulsions, thus treating these symptoms as disconnected clinical phenomena. Yet research demonstrates that there are actually dimensions of OCD symptoms that include both obsessions and compulsive rituals on the same dimension. Thus, clinicians and researchers do not have measures grounded in the proper conceptual framework for best understanding OCD symptoms. The following dimensions are most commonly found in research studies:

• Contamination obsessions with cleaning/washing (de-contamination) rituals
• Obsessions concerning responsibility for harm with checking rituals
• Unacceptable obsessive thoughts (sexual, violent, religious) with mental rituals
• Symmetry/exactness/”just right” obsessions with ordering/arranging rituals.

4) Previous OCD symptom measures do not capture avoidance behavior, which is a major symptom of many people with OCD. People with OCD who do not have many compulsions, for example, often do exhibit severe avoidance behaviors that are important to account for in estimates of overall symptom severity.

5) Many previous OCD measures include items assessing hoarding, which appears to be distinct from OCD according to the latest research. Thus, these instruments overestimate OCD symptom severity among individuals with hoarding behaviors.

Taking these limitations into account, a measure for assessing OC symptoms should (a) assess the severity of research-supported OCD symptom dimensions (excluding hoarding) in a conceptually consistent manner; (b) measure symptom severity as a function of multiple parameters; (c) include an assessment of avoidance behavior; (d) assess symptom severity independent of the number, range, or types of different obsessions and compulsions; and (e) remain fairly brief and easy to administer in clinical and research settings with clinical and nonclinical individuals.

We developed the DOCS to address the limitations of previous OCD symptom measures described above. Items on the DOCS were derived on the basis of research on the dimensionality of OCD symptoms as well as on the parameters of OCD symptom severity. The DOCS contains general descriptions and inclusive examples of obsessions and compulsions within each of the four empirically supported OCD symptom dimensions mentioned above, but does not contain items assessing specific obsessions or rituals. Rather, it assesses the severity of each symptom dimension in general and contains a multidimensional approach to severity ratings that includes the assessment of avoidance behavior.