title: Do lupus disease activity measures detect clinically important change?
abstract: OBJECTIVE
  New scales for the clinical assessment of patients with systemic lupus erythematosus (SLE) are valid and reliable, and quantitate disease activity. We assessed the responsiveness to change of 2 widely used standardized multi-item lupus activity measures, the revised Systemic Lupus Activity Measure (SLAM-R) and the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), and their ability to detect clinically relevant changes.
  
  
  METHODS
  Ninety-six (96) patients with definite SLE participated in this study. The group mean age was 45.0 (13.7) years, 91% were female, and the mean disease duration was 14.9 (7.5) years. Sociodemographic information, lupus activity (SLAM-R, SLEDAI), and damage were recorded at baseline. At each of the 5 monthly followup visits, the activity measures were repeated and a transition scale asked the physician if their patient's lupus activity had changed. Five different methods were used to compare the responsiveness of the activity measures studied: 1. the effect size; 2. the standardized response mean; 3. the control standardized response mean; 4. the area under the curve of a receiver operating characteristic (ROC) curve; and 5. a new multiple response modeling approach.
  
  
  RESULTS
  Both SLAM-R and SLEDAI are responsive. SLAM-R is consistently, although moderately, more responsive than SLEDAI. All 5 methods of evaluating responsiveness yielded a consistent ranking of disease activity measures.
  
  
  CONCLUSIONS
  SLAM-R and SLEDAI are responsive measures of lupus activity. SLAM-R appears to be more responsive than SLEDAI.
authors.affiliation: McGill University Health Center, Department of Medicine, Montreal General Hospital Research Institute, Quebec, Canada. paul.fortin@uhn.on.ca
authors.forename: P R
authors.initials: PR
authors.lastname: Fortin
authors.forename: M
authors.initials: M
authors.lastname: Abrahamowicz
authors.forename: A E
authors.initials: AE
authors.lastname: Clarke
authors.forename: C
authors.initials: C
authors.lastname: Neville
authors.forename: R
authors.initials: R
authors.lastname: Du Berger
authors.forename: L
authors.initials: L
authors.lastname: Fraenkel
authors.forename: M H
authors.initials: MH
authors.lastname: Liang
mesh_terms: D000203:Activities of Daily Living; D000328:Adult; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008137:Longitudinal Studies; D008180:Lupus Erythematosus, Systemic / Q000175:diagnosis* / Q000534:rehabilitation; D008297:Male; D008875:Middle Aged; D010808:Physical Examination; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index; D011795:Surveys and Questionnaires