How Can We Measure Obsessive-Compulsive Disorder Symptoms in Chinese Patients?

What you need to know

• The Yale-Brown Obsessive Compulsive Scale - Second Edition (Y-BOCS-II) was translated into Mandarin Chinese and tested with 86 Chinese patients with OCD.

• The Chinese version showed good reliability and validity, suggesting it can accurately measure OCD symptoms in Chinese patients.

• The Y-BOCS-II measures two main factors in OCD - obsessions and compulsions - which was confirmed in this Chinese sample.

• Having a validated OCD assessment tool in Chinese will help improve diagnosis and treatment for the millions of people with OCD in China.

Understanding obsessive-compulsive disorder

Obsessive-compulsive disorder (OCD) is a mental health condition that affects 1-2% of people worldwide. The core features of OCD are:

• Obsessions: Unwanted, intrusive thoughts or images that cause distress
• Compulsions: Repetitive behaviors or mental acts that a person feels driven to perform to reduce anxiety or prevent a feared event

For example, someone might have obsessive fears about germs and contamination, leading to compulsive hand washing. Or they may have intrusive violent thoughts, causing them to repeatedly check that they haven’t harmed anyone.

OCD can significantly impact a person’s quality of life, interfering with work, relationships, and daily activities. However, effective treatments are available, including cognitive-behavioral therapy and certain medications. To provide proper treatment, clinicians need reliable ways to assess OCD symptoms and track improvement over time.

The need for OCD assessment tools in Chinese

The Yale-Brown Obsessive Compulsive Scale (Y-BOCS) has long been considered the gold standard for measuring OCD symptom severity. However, the original version had some limitations. In response, researchers developed an updated version called the Yale-Brown Obsessive Compulsive Scale - Second Edition (Y-BOCS-II).

The Y-BOCS-II addresses previous concerns by:

• Better assessing avoidance behaviors
• Expanding the scoring range to capture more severe cases
• Removing a problematic item about resisting obsessions
• Updating the symptom checklist

While the Y-BOCS-II has been translated into a few languages, it was not previously available in Chinese. This is significant because:

• Over 1 billion people speak Chinese languages
• An estimated 2-3% of people in China experience OCD in their lifetime
• Having validated assessment tools is crucial for proper diagnosis and treatment

To address this gap, researchers set out to translate the Y-BOCS-II into Mandarin Chinese and test whether it would be a reliable and valid tool for assessing OCD in Chinese patients.

How the study was conducted

The researchers recruited 86 Chinese adults diagnosed with OCD from several outpatient psychiatry clinics. The participants ranged in age from 15 to 78 years old.

Each participant completed the following:

1. A clinical interview with a psychologist or psychiatrist to confirm their OCD diagnosis

2. The newly translated Mandarin Chinese version of the Y-BOCS-II, administered by a trained clinician

3. Two other clinician-rated measures of OCD severity:

   • Clinical Global Impression - Severity (CGI-S)
   • National Institute of Mental Health Global Obsessive Compulsive Scale (NIMH-GOCS)

4. Self-report questionnaires:

   • Obsessive-Compulsive Inventory - Revised (OCI-R) to assess OCD symptoms
   • Depression Anxiety Stress Scales (DASS-21) to measure other mental health symptoms

A subset of 25 participants completed the Y-BOCS-II again one week later to assess test-retest reliability.

The researchers then conducted statistical analyses to evaluate the psychometric properties of the Chinese Y-BOCS-II. This included examining its internal consistency, test-retest reliability, convergent validity with other OCD measures, and factor structure.

Key findings on the Chinese Y-BOCS-II

The study produced several important findings about the Mandarin Chinese version of the Y-BOCS-II:

Good reliability

• The Y-BOCS-II showed high internal consistency (Cronbach’s alpha = 0.90). This means the items on the scale consistently measure the same underlying construct of OCD severity.

• Test-retest reliability over one week was adequate (intraclass correlation = 0.63). This indicates the scale produces relatively stable scores when administered at different time points.

Evidence of validity

• The Y-BOCS-II correlated strongly with other clinician-rated measures of OCD severity (r = 0.71-0.75 with CGI-S and NIMH-GOCS). This supports its convergent validity.

• It showed moderate correlations with the self-report OCI-R (r = 0.39), suggesting it measures a similar but not identical construct.

• The Y-BOCS-II also correlated moderately with measures of depression and anxiety (r = 0.46-0.52). This may reflect high rates of other mental health conditions in people with OCD.

Two-factor structure

• Factor analysis revealed the Chinese Y-BOCS-II measures two main factors: obsessions and compulsions.

• This is consistent with the original English version and aligns with our understanding of OCD symptoms.

• One item about interference from obsessions loaded onto both factors, possibly reflecting the interconnected nature of obsessions and compulsions.

Implications for assessing OCD in Chinese patients

These results suggest the Mandarin Chinese version of the Y-BOCS-II is a reliable and valid tool for assessing OCD symptom severity in Chinese patients. This has several important implications:

1. Improved assessment: Clinicians in China now have access to the current gold standard measure for evaluating OCD symptoms. This can lead to more accurate diagnosis and treatment planning.

2. Treatment monitoring: The Y-BOCS-II can be used to track changes in symptom severity over time, helping clinicians gauge treatment effectiveness.

3. Cross-cultural research: Having a validated Chinese version allows for more direct comparisons in international OCD research.

4. Culturally appropriate care: While OCD has similar core features across cultures, having an assessment tool validated specifically with Chinese patients helps ensure culturally sensitive evaluation.

Limitations and future directions

While this study provides valuable initial support for the Chinese Y-BOCS-II, the researchers note some limitations:

• Interrater reliability (agreement between different raters) was not assessed due to practical constraints.
• Only short-term (1 week) test-retest reliability was examined. Longer intervals would be useful to assess.
• The scale’s sensitivity to detecting treatment-related changes was not evaluated.
• Detailed data on other mental health conditions participants may have had was not collected.

Future research should address these limitations. The researchers also suggest:

• Examining how the Y-BOCS-II relates to other self-report OCD measures beyond the OCI-R
• Assessing the scale’s ability to detect symptom changes with treatment
• Having an independent research group replicate these findings

Conclusions

• The Mandarin Chinese version of the Y-BOCS-II shows promise as a reliable and valid measure of OCD symptom severity in Chinese patients.

• It demonstrates good internal consistency, adequate short-term stability, and expected relationships with other mental health measures.

• The two-factor structure focusing on obsessions and compulsions aligns with our understanding of OCD.

• While more research is needed, this study represents an important step in improving OCD assessment and treatment for millions of Chinese speakers worldwide.