Comparison of the Dermatology Life Quality Index and the Children's Dermatology Life Quality Index in assessment of quality of life in patients with psoriasis aged 16-17 years

Background Dermatology Life Quality Index (DLQI) and Children's Dermatology Life Quality Index (CDLQI) are widely used to assess quality of life (QoL) in adults (>= 16 years) and children (4-16 years) with psoriasis. In the age group 16-17 years, it is not known whether DLQI and CDLQI reflect QoL impairment in the same way. Objectives To compare DLQI and CDLQI scores in patients with psoriasis aged 16-17 years. Methods Patients with psoriasis aged 16-17 years were asked to complete both the DLQI and CDLQI. Results Fifty-six patients were included. There was a high correlation between DLQI and CDLQI scores (r = 0.90, P < 0.001). The mean DLQI score (5.41 +/- 5.20) was lower than the mean CDLQI (6.61 +/- 5.74) (P < 0.001). The major part of this difference (Delta 0.61) was caused by the low score regarding sexual difficulties in the DLQI (0.11 +/- 0.49) and the high score concerning sleep in the CDLQI (0.71 +/- 0.93). In addition, the question related to sports scored 0.34 in the DLQI but 0.86 in the CDLQI (.0.52). The question related to work/study in the DLQI scored lower than the question on school/holiday in the CDLQI (Delta 0.41). Conclusions In patients with psoriasis aged 16-17 years, DLQI and CDLQI scores closely correlate, but the mean DLQI score was lower than the mean CDLQI score. This was caused primarily by differences in the answers to questions regarding sexual difficulties and sleep. As the QoL impacts experienced by people aged 16-17 may differ from those experienced by children or adults, QoL measures designed for use in this age range may have advantages over both child-and adult-specific measures.