Is the Kidscreen-27 a valid measure of health-related quality of life in 10-year-old Norwegian children?

The aim of this study was to investigate the reliability and validity of the Norwegian Kidscreen-27 questionnaire, a measure of generic health-related quality of life, in 10 year-old children. The Kidscreen-27 consists of five domains and was validated in a sample of 56 school children (29 boys). The children completed the questionnaire at three different time points during two consecutive school days. For convergent validity, the study was powered to detect a statistically significant correlation coefficient of 0.4. Cronbach's alpha values ranged from 0.73 to 0.83. Floor effects were all zero and ceiling effects ranged from 1.7% to 23.7%. Intraclass correlation values over time ranged from 0.71 to 0.81. However, some individual variability over time occurred and was illustrated by Bland Altman plots. The domains of physical well-being, psychological well-being and autonomy & parents improved over time (Ps < 0.05), while social support and school environment domains did not. We assessed convergent validity using general life satisfaction scores obtained by administering the Cantrils Ladder. All the Kidscreen-27 domains were significantly associated with general life satisfaction (Spearman rank correlations ranged from 0.29 to 0.59, Ps < 0.05). In conclusion, the Norwegian version of Kidscreen-27 has good reliability and validity.