Psychometric properties of the Chinese 15-item patient health questionnaire in the general population of Hong Kong.

OBJECTIVE

The objective was to examine the reliability and validity of the Chinese 15-item Patient Health Questionnaire (PHQ-15) in the general population of Hong Kong.

METHODS

A random community-based sample of 3014 respondents aged 15-65 was interviewed through telephone using a structured Chinese-language questionnaire that included the PHQ-15, Sheehan Disability Scale, questions about health service use and sociodemographic variables. A random subsample of 200 respondents was reinterviewed for assessing test-retest reliability.

RESULTS

The PHQ-15 exhibited satisfactory internal consistency (Cronbach's α=0.79) and stable 1-month test-retest reliability. Being female, younger age, lower education and lower income levels were associated with higher scores. "Bothered a lot" somatic symptoms were less common than in clinical studies, but their general profile was comparable to those found in Western community studies. Pains in the limbs, trouble sleeping and feeling tired (11.2%-16.9%) were the most common, whereas fainting spells and sexual problems (0.6%-0.7%) were the least so. Using principal component analysis, we extracted four clinically meaningful factors that explained 49.7% of the variance. These factors might be termed "cardiopulmonary," "gastrointestinal," "pain" and "neurological." Somatic symptom severity was positively associated with functional impairment and health service use.

CONCLUSION

The Chinese PHQ-15 exhibits satisfactory reliability and preliminary evidence of validity in a general population. Revealing a typical profile of somatic symptom severity, it is a promising tool for the empirical examination of somatization in Chinese people.