Table 1.

Kappa coefficients of the items in the low back pain questionnaire for adolescents (n = 40)

Question	Kappa value	Comment
Q1: Lifetime prevalence	0.72	Substantial
Q3: Prevalence of Recurrent NSLBP	0.51	Moderate
Q4: LBP Frequency	0.73	Substantial
Q5: LBP Duration	0.96	Perfect
Q7: Sciatica	0.32	Fair
Q8: Period prevalence	0.48	Moderate
Q10: Medical Treatment	0.56	Moderate
Q12: School Absenteeism	0.88	Perfect
Q13: School-bag	1	Perfect
Q14: School-bag weight perception	0.74	Substantial
Q15: Duration of carrying school-bag	0.86	Perfect
Q16: Method of carrying school-bag	0.83	Perfect
Q17: Sports participation	1	Perfect
Q19: Sports duration	1	Perfect
Q20: Sedentary time	0.60	Perfect
Q21: Smoking status	0.83	Perfect