title: Minimal clinically important differences in the Edmonton Symptom Assessment Scale in cancer patients: A prospective, multicenter study.
abstract: BACKGROUND
  The Edmonton Symptom Assessment Scale (ESAS) is widely used for symptom assessment in clinical and research settings. A sensitivity-specificity approach was used to identify the minimal clinically important difference (MCID) for improvement and deterioration for each of the 10 ESAS symptoms.
  
  
  METHODS
  This multicenter, prospective, longitudinal study enrolled patients with advanced cancer. ESAS was measured at the first clinic visit and at a second visit 3 weeks later. For each symptom, the Patient's Global Impression ("better," "about the same," or "worse") was assessed at the second visit as the external criterion, and the MCID was determined on the basis of the optimal cutoff in the receiver operating characteristic (ROC) curve. A sensitivity analysis was conducted through the estimation of MCIDs with other approaches.
  
  
  RESULTS
  For the 796 participants, the median duration between the 2 study visits was 21 days (interquartile range, 18-28 days). The area under the ROC curve varied from 0.70 to 0.87, and this suggested good responsiveness. For all 10 symptoms, the optimal cutoff was ≥1 point for improvement and ≤-1 point for deterioration, with sensitivities of 59% to 85% and specificities of 69% to 85%. With other approaches, the MCIDs varied from 0.8 to 2.2 for improvement and from -0.8 to -2.3 for deterioration in the within-patient analysis, from 1.2 to 1.6 with the one-half standard deviation approach, and from 1.3 to 1.7 with the standard error of measurement approach.
  
  
  CONCLUSIONS
  ESAS was responsive to change. The optimal cutoffs were ≥1 point for improvement and ≤-1 point for deterioration for each of the 10 symptoms. Our findings have implications for sample size calculations and response determination.
authors.affiliation: Department of Palliative Care and Rehabilitation Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: David
authors.initials: D
authors.lastname: Hui
authors.affiliation: Department of Palliative Care, King Hussein Cancer Center, Amman, Jordan.
authors.forename: Omar
authors.initials: O
authors.lastname: Shamieh
authors.affiliation: Department of Medical Oncology, Barretos Cancer Hospital, Barretos, Brazil.
authors.forename: Carlos Eduardo
authors.initials: CE
authors.lastname: Paiva
authors.affiliation: Department of Internal Medicine, School of Medicine, Pontificia Universidad Catolica de Chile, Santiago, Chile.
authors.forename: Pedro Emilio
authors.initials: PE
authors.lastname: Perez-Cruz
authors.affiliation: Department of Medical Oncology, Kangdong Sacred Heart Hospital, Seoul, Republic of Korea.
authors.forename: Jung Hye
authors.initials: JH
authors.lastname: Kwon
authors.affiliation: Department of Palliative Care, Tata Memorial Center, Mumbai, India.
authors.forename: Mary Ann
authors.initials: MA
authors.lastname: Muckaden
authors.affiliation: Department of Biostatistics, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Minjeong
authors.initials: M
authors.lastname: Park
authors.affiliation: Department of Palliative Care and Rehabilitation Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Sriram
authors.initials: S
authors.lastname: Yennu
authors.affiliation: Division of Hematology/Oncology, Department of Internal Medicine, Gyeongsang University College of Medicine, Gyeongsang, Republic of Korea.
authors.forename: Jung Hun
authors.initials: JH
authors.lastname: Kang
authors.affiliation: Department of Palliative Care and Rehabilitation Medicine, The University of Texas MD Anderson Cancer Center, Houston, Texas.
authors.forename: Eduardo
authors.initials: E
authors.lastname: Bruera
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009369:Neoplasms / Q000175:diagnosis*; D011446:Prospective Studies; D011788:Quality of Life; D012372:ROC Curve; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires; D063189:Symptom Assessment
keywords: neoplasms; outcome measures; pain; sample size; sensitivity and specificity; symptom assessment