Table 3.

Mean scores in the sections of NDI questionnaire.

NDI	Study group N = 60
	$\overline{x}$	Me	Min	Max	S
Pain intensity	1.2	1.0	0.0	4.0	1.2
Personal care	0.6	0.0	0.0	3.0	0.7
Lifting	1.1	1.0	0.0	4.0	1.2
Reading	0.5	0.0	0.0	4.0	0.9
Headaches	0.8	1.0	0.0	4.0	0.7
Concentration	0.3	0.0	0.0	3.0	0.6
Work	0.8	0.0	0.0	5.0	1.3
Driving	0.8	1.0	0.0	5.0	1.2
Sleeping	0.4	0.0	0.0	3.0	0.6
Recreation	0.3	0.0	0.0	3.0	0.7
NDI—total score	6.7	5.0	0.0	30.0	6.8
NDI—per cent score	13.5%	10.0%	0.0%	60.0%	13.7%

$\overline{x}$ mean, Me median, S standard deviation, Min minimum value, Max maximum value.