Context: Few studies have shown that diagnostic palpation is reliable. No studies have shown that the reliability of diagnostic palpatory skills can be maintained and improved over time.
Objectives: To investigate whether the reliability of selected palpatory tests used to identify lumbar somatic dysfunction was maintained during a 4-month period as part of a clinical observational study.
Methods: Participants with low back pain and participants without low back pain, recruited from a rural Midwestern community, were examined during 6 separate sessions over a 4-month period. During each data collection session, two blinded examiners, who had previously completed comprehensive consensus training, evaluated the lumbar region with four tests: static segmental positional asymmetry of the transverse processes in the horizontal plane, tissue texture abnormalities, resistance to anterior springing on the spinous processes, and tenderness induced by pressure on the spinous processes. Detailed protocols for each test were defined during a previous comprehensive consensus training period and were not revised during the current study. To verify that established interobserver reliability was maintained throughout the clinical study, quality control sampling was performed on all data. When findings were inconsistent between the two examiners, focused consensus training was performed as a means of recalibration to understand why assessments were inconsistent. Interobserver reliability for determining the presence or absence of somatic dysfunction was assessed using kappa coefficients.
Results: The study enrolled 64 participants, and 14 to 33 participants were examined per session. All four tests had acceptable interobserver reliability by the final data collection session. The test for static segmental positional asymmetry of the transverse processes in the horizontal plane had moderate to substantial reliability in all 6 sessions. The test for tissue texture abnormalities had moderate reliability in 5 of the 6 sessions. The test for resistance to anterior springing on the spinous processes had moderate reliability for 3 of the 6 sessions. The test for tenderness had substantial to almost perfect reliability for all 6 sessions. In general, interobserver reliability improved over time.
Conclusions: Examiners were able to maintain and improve interobserver reliability of four lumbar diagnostic palpatory tests over a 4-month period.