title: Lumbar spinal stenosis-specific symptom scale: validity and responsiveness.
abstract: METHODS
  Cross-sectional study.
  
  
  OBJECTIVE
  To test the validity and responsiveness of the lumbar spinal stenosis (LSS)-specific symptom scale (FLS-25 [Fukushima LSS Scale 25]).
  
  
  BACKGROUND
  The FLS-25, a self-administered questionnaire designed to comprehensively cover various symptoms of LSS, has been developed to address the need to measure symptoms specific to this disorder.
  
  
  METHODS
  One hundred sixty-seven patients with confirmed LSS who required conservative therapy were asked to complete a questionnaire including questions regarding walking capacity and the FLS-25. These patients also underwent a lumbar extension test and a walking stress test, which are stress tests designed to objectively evaluate LSS symptoms, to measure standing time, walking distance, and walking time. Relationship between the FLS-25 scores and these external standards was analyzed to evaluate the criterion validity of the FLS-25. The patients underwent the same evaluations after 8 weeks of conservative therapy. The relationship between changes from baseline to week 8 in FLS-25 scores and changes in the 3 external standards was analyzed to evaluate the responsiveness of the FLS-25.
  
  
  RESULTS
  The distribution of FLS-25 scores among patients was symmetric, and there were no ceiling or floor effects. FLS-25 scores increased as self-reported walking capacity decreased (P=0.006). The mean standing time in the lumbar extension test was 165 (SD=109) seconds, and FLS-25 scores increased as standing time decreased (P=0.003). In the walking stress test, mean walking distance and mean walking time were 213 (SD=154) m and 236 (SD=114) seconds. FLS-25 scores increased as walking distance (P=0.002) and walking time (P=0.054) decreased. Changes from baseline to week 8 in FLS-25 scores correlated with changes in the stress test standing time (P=0.014), walking distance (P<0.001), and walking time (P<0.001).
  
  
  CONCLUSIONS
  The criterion validity and responsiveness of the FLS-25 were confirmed. The use of FLS-25 in clinical and investigational settings is warranted to monitor patients and evaluate therapeutic efficacy.
  
  
  METHODS
  3.
authors.affiliation: *Department of Orthopaedic Surgery, Fukushima Medical University School of Medicine, Fukushima, Japan †Department of Sociology, Kansai University, Osaka, Japan ‡Institute for Health Outcomes & Process Evaluation Research (iHope International), Kyoto, Japan §Department of Healthcare Epidemiology, Kyoto University, Kyoto, Japan; and ¶Center for Innovative Research for Communities and Clinical Excellence, Fukushima Medical University, Fukushima, Japan.
authors.forename: Miho
authors.initials: M
authors.lastname: Sekiguchi
authors.forename: Takafumi
authors.initials: T
authors.lastname: Wakita
authors.forename: Koji
authors.initials: K
authors.lastname: Otani
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Onishi
authors.forename: Shunichi
authors.initials: S
authors.lastname: Fukuhara
authors.forename: Shin-Ichi
authors.initials: S
authors.lastname: Kikuchi
authors.forename: Shin-ichi
authors.initials: S
authors.lastname: Konno
mesh_terms: D000328:Adult; D000368:Aged; D003430:Cross-Sectional Studies; D005080:Exercise Test / Q000379:methods / Q000592:standards*; D005260:Female; D006801:Humans; D008159:Lumbar Vertebrae / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D012720:Severity of Illness Index; D013130:Spinal Stenosis / Q000175:diagnosis* / Q000503:physiopathology; D011795:Surveys and Questionnaires / Q000592:standards*