Test performance of the Cantonese Chinese Mood Disorder Questionnaire for detecting bipolar spectrum disorder in the community of Hong Kong.

Dear Editor Bipolar spectrum disorder (BSD) is common in the general population with a lifetime prevalence of 2.4–5%. A recent cross-national community epidemiological study confirmed that it is a common and valid illness entity across 11 countries (Merikangas et al., 2011). Although BSD has been uncommonly studied in community settings (Benazzi, 2007; Lee et al., 2009), its early age of onset, high prevalence, typically late recognition and impairing nature (Merikangas et al., 2011) have prompted recent interest in early detection in both clinical and community settings. The underrecognition of BSD (Akiskal et al., 2000) may be improved by enhancing the reliability and validity of screening instruments (Young & MacPherson, 2011). The Mood Disorder Questionnaire (MDQ) is commonly used to screen for lifetime manic or hypomanic syndromes (Hirschfeld, 2002). Validation studies across different settings have not produced consistent results. Overall, they found its English and several non-English versions to exhibit moderate sensitivity and high specificity for assessing bipolar disorder among clinical samples (Hirschfeld et al., 2003). However, it was less commonly examined in the community and was usually used for the screening of bipolar I (BP-I) and bipolar II (BP-II) disorders rather than BSD. Available studies suggested that it exhibited a much lower sensitivity for bipolar disorder in community studies than in clinical studies (Hirschfeld et al., 2003), and that seemed to be especially so in a Chinese setting (Chung et al., 2009). The restrictive criteria of bipolar disorder and the telephone-based mode of clinical reappraisal interviews adopted in these studies might have contributed to the finding of low sensitivity. Moreover, these studies used the single four-level impairment item in the original MDQ which validation studies had found to adversely affect sensitivity (Weber Rouget et al., 2005; Chung et al., 2008; Kim et al., 2008). The role of the MDQ in screening for BSD has not been studied in Chinese populations before. The present study examined the concordance of the Chinese MDQ with face-to-face clinical diagnostic interviews in a general population setting. A clinical diagnosis of BSD referred to the Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV) diagnoses of BP-I and BP-II disorder, as well as bipolar disorder not otherwise specified (NOS) which consists of major depressive episode accompanied by sub-threshold hypomania lasting 2–3 days. We attempted to improve on the previous community studies in several ways. We replaced the single four-level impairment item of the MDQ with the multi-domain Sheehan Disability Scale (SDS) (Leon et al., 1997). In translating the MDQ, we paid attention to the contextual meanings of the items with a view to enhancing their sensitivity without unduly changing the original meanings. Finally, we conducted detailed face-to-face interviews using an enhanced version of the Structured Clinical Interview for DSM-IV (SCID) that assesses a spectrum of hypomania beyond conventionally recognized bipolar disorder (Benazzi & Akiskal, 2003).