title: The reliability and validity of the computerized double inclinometer in measuring lumbar mobility.
abstract: METHODS
  Repeated measures reliability/validity study.
  
  
  OBJECTIVE
  To determine the concurrent validity, test-retest, inter-rater and intra-rater reliability of lumbar flexion and extension measurements using the Tracker M.E. computerized dual inclinometer (CDI) in comparison to the modified-modified Schober (MMS).
  
  
  BACKGROUND
  Numerous studies have evaluated the reliability and validity of the various methods of measuring spinal motion, but the results are inconsistent. Differences in equipment and techniques make it difficult to correlate results.
  
  
  METHODS
  Twenty subjects with back pain and twenty without back pain were selected through convenience sampling. Two examiners measured sagittal plane lumbar range of motion for each subject. Two separate tests with the CDI and one test with the MMS were conducted. Each test consisted of three trials. Instrument and examiner order was randomly assigned. Intra-class correlations (ICCs 2, 2 and 2, 2) and Pearson correlation coefficients (r) were used to calculate reliability and concurrent validity respectively.
  
  
  RESULTS
  Intra-trial reliability was high to very high for both the CDI (ICCs 0.85 - 0.96) and MMS (ICCs 0.84 - 0.98). However, the reliability was poor to moderate, when the CDI unit had to be repositioned either by the same rate (ICCs 0.16 - 0.59) or a different rater (ICCs 0.45 - 0.52). Inter-rater reliability for the MMS was moderate to high (ICCs 0.75 - 0.82) which bettered the moderate correlation obtained for the CDI (ICCs 0.45 - 0.52). Correlations between the CDI and MMS were poor for flexion (0.32; p<0.05) and poor to moderate (-0.42 - -0.51; p<0.05) for extension measurements.
  
  
  CONCLUSIONS
  When using the CDI, an average of subsequent tests is required to obtain moderate reliability. The MMS was highly reliable than the CDI. The MMS and the CDI measure lumbar movement on a different metric that are not highly related to each other.
authors.affiliation: McMaster University, School of Rehabilitation Science, Hamilton, Ontario, Canada; Roth-MacFarlane Hand and Upper Limb Center, St. Joseph's Hospital, London, Ontario, Canada.
authors.forename: Joy Christine
authors.initials: JC
authors.lastname: MacDermid
authors.affiliation: University of Western Ontario, Health and Rehabilitation Sciences, Faculty of Health Sciences, London, Ontario, Canada.
authors.forename: Vanitha
authors.initials: V
authors.lastname: Arumugam
authors.affiliation: University of Western Ontario, Health and Rehabilitation Sciences, Faculty of Health Sciences, London, Ontario, Canada.
authors.forename: Joshua Israel
authors.initials: JI
authors.lastname: Vincent
authors.affiliation: School of Rehabilitation Science, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Krista L
authors.initials: KL
authors.lastname: Carroll
keywords: Computerized dual inclinometer; construct validity.; low back pain; modified-modified Schober; reliability