title: Psychometric comparison of single-item, short, and comprehensive depression screening measures in Korean young adults.
abstract: BACKGROUND
  Integrating long depression-screening instruments into routine clinical practice and research studies is often impractical, necessitating short-item if not single-item measures with comparable psychometric properties.
  
  
  OBJECTIVE
  To examine whether single-item or short depression-screening measures are comparable to a comprehensive screening measure in reliability (i.e., internal consistency and test-retest reliability) and validity (i.e., convergent, concurrent, and predictive validity) in Korean young adults within a Classical Testing Theory framework.
  
  
  METHODS
  A total of 458 students from six nursing colleges in South Korea completed three depression measures: the 20-item Center for Epidemiologic Studies-Depression screening instrument (CES-D; comprehensive measure); the five-item Profile of Mood States-Brief depression subscale (POMS-B depression subscale; short measure); a single-item Likert measure; and a single-item numeric rating scale. Internal consistency reliability was tested by Cronbach's alpha and item-total correlations; test-retest reliability by intraclass correlation coefficient (ICC); convergent validity by correlation with the CES-D; concurrent validity by the correlation with perceived stress level and sleep quality; and predictive validity by receiver operating characteristic curve to predict the two groups with different depression levels.
  
  
  RESULTS
  The POMS-B depression subscale was comparable to the comprehensive CES-D scale in internal consistency reliability (alpha=.85); test-retest reliability (ICC=.76); and convergent (r=.81 with CES-D), concurrent (r=.64 with perceived stress level, r=.34 with sleep quality), and predictive validity (area under the curve=.88). The two single-item options were not comparable to the comprehensive CES-D.
  
  
  CONCLUSIONS
  The short POMS-B depression subscale shows an acceptable balance between practical clinical and research needs and psychometric quality.
authors.affiliation: College of Nursing, Catholic University of Korea, Seoul, South Korea. Electronic address: heeju0906@gmail.com.
authors.forename: Hee-Ju
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Department of Pharmacy Practice and Science, College of Pharmacy, University of Arizona, Tucson, AZ, USA; Department of Family and Community Medicine, College of Medicine, University of Arizona, Tucson, AZ, USA; Center for Health Outcomes and PharmacoEconomic Research, University of Arizona, Tucson, AZ, USA.
authors.forename: Ivo
authors.initials: I
authors.lastname: Abraham
mesh_terms: D000328:Adult; D003863:Depression / Q000175:diagnosis*; D006801:Humans; D011594:Psychometrics; D056910:Republic of Korea; D055815:Young Adult
keywords: Depression; Metric systems; Psychometrics; Validation studies