CHIROPRACTIC BIOPHYSICS LATERAL CERVICAL FILM ANALYSIS RELIABILITY

Objective: To determine the degree to which the geometric line drawing s used in Chiropractic Biophysics Technique (CBP) on lateral cervical radiographs are reliable. Design: A blind, delayed repeated measures d esign was used. Three examiners were presented radiographs in random o rder. All identifying marks were removed prior to each examiner's indi vidual marking and measurement. Each examiner was blinded as to how th e previous examiners marked and measured the radiographs. Setting: Pri mary care private chiropractic clinic. Patients, Participants: Sixty-f ive subject films were provided from the patient records of a primary care private chiropractic clinic. The 65 radiographs qualified for inc lusion in the study based on two criteria: C1 through C7 had to be cle arly visible, and there had to be no identifying artifacts. Main Outco me Measures: Anterior head translation in millimeters, atlas plane to horizontal, Ruth Jackson's cervical stress lines, and five relative ro tation angles for C2-C3, C3-C4. C4-C5, C5-C6, C6-C7. Inter- and intrar eliability of the three examiners were statistically analyzed. Results : Intraexaminer for a) C1 to horizontal reliability was .98-.99 with c onfidence intervals of .96-.99, b) absolute rotation angle from C2 to C7 reliability was .82-.95 with confidence intervals of .80-.99, c) an terior head translation [+S(z)] reliability was.86-.99, with confidenc e intervals of .74-.99, d) relative rotation angle reliability ranges were (C2-C3) .99, and (C3-C4) .98. 99, (C4-C5) .88-.99, (C5-C6) .80-.9 9, and (C6-C7) .94-.98. Interexaminer reliabilities across examiners r anged from a) Winer: .89-.99 and b) Bartko: .72-.96. Conclusions: The reliabilities for intra- and interexaminer were all greater than .70, indicating that these measurements in CBP technique would be considere d accurate enough to provide measurements for future clinical studies. The data indicated that the C6-C7 relative rotation angle was the lea st reliable measurement. This might be due to the very small angles fo und at this level.