Allowing a Possible Margin of Error When Assessing Student Skills in Spinous Process Location

Abstract

Introduction: Spinal palpation is subject to inconsistency between examiners. When testing students on the location of vertebral spinous processes, faculty examiners may wish to allow for a margin of error that is observed between experienced practitioners. This study attempts to determine such a margin of error for selected vertebral levels that could be allowed in testing situations at Sherman Chiropractic College. This could serve as a model for other chiropractic colleges in determining their margins of error. Methods: Two faculty clinicians palpated spinous processes at four different vertebral levels (C2, T3, T9, and L2) on 18 student volunteers. Differences for each vertebral level, along with one, two, and three standard deviations, were calculated. Results: Average differences between examiners increased caudally, as follows: C2, 4.23 ± 3.77 mm; T3, 13.41 ± 10.53 mm; T9, 18.17 ± 17.62 mm; L2, 18.70 ± 16.58 mm. Discussion: In this study, faculty examiners exhibited variation in their locations of spinous processes for these vertebrae. These variations could be allowed when assessing student skills in locating these spinous processes at this chiropractic college. Conclusion: In this study, differences between examiners plus or minus one standard deviation ranged from 4.23 ± 3.77 mm for C2 to 18.70 ± 16.58 mm for L2. The concept of margin of error should be considered by faculty examiners when assessing the skill of students in locating the spinous process of various vertebral levels.