title: Validation of the Edmonton Symptom Assessment System in Korean patients with cancer.
abstract: BACKGROUND
  The Edmonton Symptom Assessment System (ESAS) is a brief, widely adopted, multidimensional questionnaire to evaluate patient-reported symptoms.
  
  
  OBJECTIVE
  To develop a Korean version of the ESAS (K-ESAS) and to perform a psychometric analysis in Korean patients with advanced cancer.
  
  
  METHODS
  We tested the K-ESAS in two pilot studies with 15 patients each. We assessed internal consistency, test-retest reliability, and concurrent validity in 163 Korean patients, who completed the K-ESAS along with the Korean versions of the M. D. Anderson Symptom Inventory (K-MDASI) and the Hospital Anxiety and Depression Scale (K-HADS) twice. A total of 38 patients completed the questionnaires again seven days later to assess responsiveness.
  
  
  RESULTS
  The K-ESAS scores had good internal consistency, with a Cronbach's alpha coefficient of 0.88, indicating that no questions had undue influence on the score. Pearson correlation coefficients for K-ESAS symptom scores between baseline and after two to four hours ranged from 0.72 (95% CI 0.64-0.79) to 0.87 (95% CI 0.82-0.90), indicating strong test-retest reliability. For concurrent validity, Pearson correlation coefficients between K-ESAS symptom scores and corresponding K-MDASI symptom scores ranged from 0.70 (95% CI 0.62-0.77) to 0.83 (95% CI 0.77-0.87), indicating good concurrent validity. For the K-HADS, concurrent validity was good for anxiety (r=0.73, 95% CI 0.65-0.79) but moderate for depression (r=0.4, 95% CI 0.26-0.52). For responsiveness, changes in K-ESAS scores after seven days were moderately correlated with changes in K-MDASI scores but weakly correlated with changes in K-HADS scores.
  
  
  CONCLUSIONS
  The K-ESAS is a valid and reliable tool for measuring multidimensional symptoms in Korean patients with cancer.
authors.affiliation: Department of Internal Medicine, Kangdong Sacred Heart Hospital, Hallym University, Seoul, Republic of Korea; Department of Palliative Care and Rehabilitation Medicine, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA.
authors.forename: Jung Hye
authors.initials: JH
authors.lastname: Kwon
authors.forename: Seung-Hyun
authors.initials: SH
authors.lastname: Nam
authors.forename: Sujin
authors.initials: S
authors.lastname: Koh
authors.forename: Young Seon
authors.initials: YS
authors.lastname: Hong
authors.forename: Kyung Hee
authors.initials: KH
authors.lastname: Lee
authors.forename: Sang-Won
authors.initials: SW
authors.lastname: Shin
authors.forename: David
authors.initials: D
authors.lastname: Hui
authors.forename: Kyun Woo
authors.initials: KW
authors.lastname: Park
authors.forename: So Young
authors.initials: SY
authors.lastname: Yoon
authors.forename: Ji Yun
authors.initials: JY
authors.lastname: Won
authors.forename: Gary
authors.initials: G
authors.lastname: Chisholm
authors.forename: Eduardo
authors.initials: E
authors.lastname: Bruera
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000175:diagnosis* / Q000453:epidemiology* / Q000523:psychology; D015995:Prevalence; D011594:Psychometrics / Q000379:methods* / Q000706:statistics & numerical data; D011788:Quality of Life; D015203:Reproducibility of Results; D056910:Republic of Korea / Q000453:epidemiology; D012680:Sensitivity and Specificity; D011795:Surveys and Questionnaires; D063189:Symptom Assessment / Q000379:methods* / Q000706:statistics & numerical data
keywords: Advanced cancer; ESAS; Edmonton Symptom Assessment System; Korea