448 TREATMENT OF SPECIFIC ANXIETY DISORDERS
Definitions
Obsessions can take the form of repetitive, distressing, and intrusive thoughts, images,
or impulses, although obsessive thoughts are by far the most common symptom presen-
tation. Obsessional content can be highly idiosyncratic and shaped by the individual’s
personal experiences, sociocultural influences, and critical life incidents (for further dis-
cussion, see D. A. Clark, 2004; de Silva, 2003; Rachman & Hodgson, 1980). However,
certain themes are more common than others, such as:
- A concern about dirt or contamination (e.g., “Did I soil this chair, thereby
exposing others to my feces and possible contamination?”). - Disease and illness (e.g., “I can’t open this door because the doorknob is covered
with germs that could inflict me with a deadly disease.”). - Doubts about security (e.g., “Did I lock the door when I left the office this eve-
ning?”). - Violence and injury (e.g., “Did I accidentally run over the pedestrian I just passed
while driving?”). - Personally repulsive sexual acts (e.g., “Am I sexually attracted to children?”).
- Immorality and religion (e.g., “Did I completely confess all of my sins to
God?”). - Miscellaneous topics (i.e., persistent concerns about order, symmetry, exactness,
routine, and numbers).
Based on a study of more than 1,000 patients with OCD Rasmussen and Eisen (1992,
1998) reported that fear of contamination (50%) and pathological doubt (42%) were
the most common obsessions, whereas symmetry (32%), aggression (31%), sex (24%),
and religion (10%) were less common. The following is a working definition of obses-
sions:
Clinician Guideline 11.1
Obsessions are highly repetitive unwanted and unacceptable thoughts, images, or impulses
that are associated with subjective resistance, are difficult to control, and generally produce
distress even though the individual may recognize that the thought may be highly exagger-
ated, irrational, or even senseless to varying degrees (Rachman, 1985).Compulsions are repetitive, stereotyped overt behaviors or mental acts that are
associated with a strong subjective urge to perform even though the individual may
desire to resist the response to varying degrees (Taylor, Abramowitz, & McKay, 2007).
A compulsion usually involves some overt action such as repeated hand washing or
checking, but it can also be a covert or cognitive response like a subvocal rehearsal of
certain words, phrases, or a prayer. Overt compulsions, however, like repeated check-
ing (61%), washing/cleaning (50%), or reassurance seeking (34%) are most common,
whereas symmetry/precision (28%) and hoarding (18%) are least common (Rasmussen
& Eisen, 1998). In the DSM-IV field trial for OCD, Foa and Kozak (1995) found that