The McKenzie classification system in the extremities: a reliability study using McKenzie assessment forms and experienced clinicians.

OBJECTIVE: This study investigated the reliability of experienced physiotherapists in classifying patients in McKenzie nonspecific mechanical syndromes from extremity McKenzie assessment forms.

METHODS: Real patient vignettes (N = 25) were collected during clinical practice; all identifying information was removed to make the assessment form anonymous, and the mechanical classification chosen by the treating therapist was also deleted. The forms were saved in an electronic format. Forms and a sheet to be filled in for classification for each vignette and demographic details were sent electronically to McKenzie Institute International Diploma holders worldwide. Three repeat mailings were undertaken to maximize response rates.

RESULTS: Of a sample frame of 126 therapists, 97 responded and provided classification for the patient vignettes. Overall agreement was 92% and the kappa value was 0.83.

CONCLUSION: This reliability analysis of McKenzie extremity assessment forms showed a good level of reliability among the participating experienced therapists.