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Obsessive-Compulsive Disorder (OCD)


Obsessive-compulsive disorder (OCD) is often a long-lasting disorder in which a person has uncontrollable, reoccurring thoughts (obsessions), and behaviors (compulsions) that he or she feels the urge to repeat over and over.

Additional information about obsessive-compulsive disorder can be found on the NIMH Health Topics page on Obsessive-Compulsive Disorder.

Prevalence of Obsessive-Compulsive Disorder Among Adults

  • Based on diagnostic interview data from the National Comorbidity Survey Replication (NCS-R), Figure 1 shows past year prevalence of OCD among U.S. adults aged 18 or older.1
    • An estimated 1.2% of U.S. adults had OCD in the past year.
    • Past year prevalence of OCD was higher for females (1.8%) than for males (0.5%).
  • Lifetime prevalence of OCD among U.S. adults was 2.3%.2

Figure 1

Past Year Prevalence of Obsessive-Compulsive Disorder Among U.S Adults (2001-2003)
Demographic Percent
Overall 1.2
Sex Female 1.8
Male 0.5
Age 18-29 1.5
30-44 1.4
45-59 1.1
60+ 0.5

Obsessive-Compulsive Disorder with Impairment Among Adults

  • Of adults with OCD in the past year, degree of impairment ranged from mild to severe, as shown in Figure 2. Impairment was determined by scores on the Sheehan Disability Scale.
    • Among adults with OCD, approximately one half (50.6%) had had serious impairment.1
    • Another 34.8% of adults with OCD had moderate impairment, and 14.6% had mild impairment.1

Figure 2

Past Year Severity of Obsessive-Compulsive Disorder Among U.S. Adults (2001-2003)
Severity Percent
Mild 14.6
Moderate 34.8
Serious 50.6
Total 100

Data Sources


  1. Harvard Medical School, 2007. National Comorbidity Survey (NCSSC). (2017, August 21). Retrieved from . Data Table 2: 12-month prevalence DSM-IV/WMH-CIDI disorders by sex and cohort. 
  2. Harvard Medical School, 2007. National Comorbidity Survey (NCSSC). (2017, August 21). Retrieved from . Data Table 1: Lifetime prevalence DSM-IV/WMH-CIDI disorders by sex and cohort. 
  3. Kessler RC, Chiu WT, Demler O, Merikangas KR, Walters EE. Prevalence, severity, and comorbidity of 12-month DSM-IV disorders in the National Comorbidity Survey Replication. Arch Gen Psychiatry. 2005 Jun;62(6):617-27. PMID: 15939839 

Statistical Methods and Measurement Caveats

National Comorbidity Survey Replication (NCS-R)

Diagnostic Assessment and Population:

  • The NCS-R is a nationally representative, face-to-face, household survey conducted between February 2001 and April 2003 with a response rate of 70.9%. Diagnostic and Statistical Manual of Mental Disorder, Fourth Edition (DSM-IV) mental disorders were assessed using a modified version of the fully structured World Health Organization Composite International Diagnostic Interview (WMH-CIDI), a fully structured lay-administered diagnostic interview that generates both International Classification of Diseases, 10th Revision, and DSM-IV diagnoses. The DSM-IV criteria were used here. The Sheehan Disability Scale (SDS) assessed disability in work role performance, household maintenance, social life, and intimate relationships on a 0–10 scale. Participants for the main interview totaled 9,282 English-speaking, non-institutionalized, civilian respondents. Obsessive-compulsive disorder (OCD) was assessed in a subsample of 1,808 adults. The NCS-R was led by Harvard University.
  • Unlike the DSM-IV criteria used in the NCS-R, the current DSM-5 no longer places OCD in the anxiety disorder category. It is listed in a new DSM-5 category, “Obsessive-Compulsive and Related Disorders.”

Survey Non-response:

  • In 2001-2002, non-response was 29.1% of primary respondents and 19.6% of secondary respondents. Reasons for non-response to interviewing include: refusal to participate (7.3% of primary, 6.3% of secondary); respondent was reluctant- too busy but did not refuse (17.7% of primary, 11.6% of secondary); circumstantial, such as intellectual developmental disability or overseas work assignment (2.0% of primary, 1.7% of secondary); and household units that were never contacted (2.0%).
  • For more information, see PMID: 15297905 .