Table 7.

Intra-class correlation coefficients for reliability

Questionnaire domain	Intra-class correlation coefficient	95%CI
NDI	0.93	0.86–0.97
VAS	0.87	0.72– 0.94
SF36 Physical	0.94	0.89–0.97
SF36 Role Physical	0.83	0.66–0.92
SF36 Pain	0.91	0.81–0.96
SF36 General Health	0.93	0.86–0.97
SF36 Energy	0.91	0.81–0.96
SF36 Social	0.91	0.82–0.96
SF36 Role Mental	0.81	0.60–0.91
SF36 Mental Health	0.90	0.80–0.95