Validity of Radiographic Analyses Between Hand-Drawn and Computer- Aided Measurements: A Double-Blinded Test-Retest Trial

Abstract

Background: Spinal radiographic analyses are valid and reliable practices used for patient management in healthcare. Technologies and tools used for these analyses need to be valid and reliable.

Objective: This study investigates repeated accuracy for validity and intra- and inter-examiner reliability of computer-aided lateral spinal radiograph measurements using PostureRay^® EMR software.

Methods: Rectangle renderings representing lateral spinal radiographic views were created to remove examiner interpretation of anatomical landmarks as performed on actual radiographs to examine the objective repeated accuracy of PostureRay^® software. A blind, randomized, repeated measure design was performed using four examiners trained and experienced with the Harrison Posterior Tangent method of measurement. Each examiner analyzed the spine renderings using a hand-drawn and PostureRay ^® method multiple times. A fully crossed design whereby examiners performed multiple assessments per rendering using each analysis method was used to assess intra- and inter-examiner reliability within each method and a formal comparison of the two methods.

Results: Using hand-drawn and PostureRay^® methods, examiners displayed very high intra-examiner reliability with correlation values greater than 0.999 for each combination of trials. PostureRay^® method showed consistent accuracy of measurements. Further, there was no statistical difference in average concordance between hand-drawn and PostureRay^® methods for the lateral cervical, thoracic, and thoracolumbosacral spinal regions.

Conclusion: This study reports a very high degree of intra- and inter-examiner reliability of radiographic line drawing methods and establishes concurrent validity of PostureRay^® EMR software in determining angles and displacements of lateral spinal alignment as an equivalent method to the handdrawn method.

Keywords: Harrison ideal spine model; PostureRay^®; X-ray; ZhangzhouHarrison posterior tangent method; mensuration; radiography; reliability; spine; validity.