title: Reliability and validity of the photogrammetry for scoliosis evaluation: a cross-sectional prospective study.
abstract: OBJECTIVE
  The purpose of this study was to investigate the reliability and validity of photogrammetry in measuring the lateral spinal inclination angles.
  
  
  METHODS
  Forty subjects (32 female and 8 males) with a mean age of 23.4 +/- 11.2 years had their scoliosis evaluated by radiographs of their trunk, determined by the Cobb angle method, and by photogrammetry. The statistical methods used included Cronbach alpha, Pearson/Spearman correlation coefficients, and regression analyses.
  
  
  RESULTS
  The Cronbach alpha values showed that the photogrammetric measures showed high internal consistency, which indicated that the sample was bias free. The radiograph method showed to be more precise with intrarater reliabilities of 0.936, 0.975, and 0.945 for the thoracic, lumbar, and thoracolumbar curves, respectively, and interrater reliabilities of 0.942 and 0.879 for the angular measures of the thoracic and thoracolumbar segments, respectively. The regression analyses revealed a high determination coefficient although limited to the adjusted linear model between the radiographic and photographic measures. It was found that with more severe scoliosis, the lateral curve measures obtained with the photogrammetry were for the thoracic and lumbar regions (R = 0.619 and 0.551).
  
  
  CONCLUSIONS
  The photogrammetric measures were found to be reproducible in this study and could be used as supplementary information to decrease the number of radiographs necessary for the monitoring of scoliosis.
authors.affiliation: School of Medicine, Vale do São Francisco Federal University, Petrolina, Brazil. karenruggeri@usp.br
authors.forename: Karen Ruggeri
authors.initials: KR
authors.lastname: Saad
authors.forename: Alexandra S
authors.initials: AS
authors.lastname: Colombo
authors.forename: Silvia M Amado
authors.initials: SM
authors.lastname: João
mesh_terms: D000328:Adult; D000886:Anthropometry / Q000379:methods; D015992:Body Mass Index; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D008297:Male; D015588:Observer Variation; D018579:Patient Selection; D010780:Photogrammetry / Q000295:instrumentation / Q000379:methods* / Q000592:standards; D026741:Physical Therapy Modalities; D011446:Prospective Studies; D011859:Radiography / Q000592:standards; D012044:Regression Analysis; D012600:Scoliosis / Q000175:diagnosis*; D012720:Severity of Illness Index; D018709:Statistics, Nonparametric