Background: Chronic disease can have physical and psychological effects which affect social functioning. These effects can be better understood from the perspective of parent and child by the use of health-related quality of life (HRQL) measures. Various HRQL measures are now available, of which generic health measures have been the most widely used. These permit comparison between different diseases and also the normal population.
Objectives: To cross-validate a new generic HRQL proxy measure for children, the Children's Life Quality Index (CLQI), with an established speciality-specific dermatological questionnaire, the Children's Dermatology Life Quality Index (CDLQI), in a group of children with chronic skin diseases. The impairment of HRQL in the same group of children with skin disease was then compared with that associated with other common chronic childhood diseases using the CLQI.
Methods: The CDLQI was completed by 379 children aged 5-16 years with skin disease of more than 6 months' duration. Their parents (n=379) and parents of 161 children aged 5-16 years with other chronic diseases were also asked to complete a proxy measure, the CLQI.
Results: Using linear regression analysis, the CLQI and the CDLQI scores showed a strong linear association (rs=0.72, P<0.001) and on a Bland-Altman plot, reasonably good agreement (expressing scores out of 100, the 95% limits of agreement were from -25.5/100 to 26.7/100). In the child's opinion psoriasis and atopic dermatitis (AD) caused the greatest impairment (CDLQI scores of 30.6% and 30.5%), followed by urticaria (20%) and acne (18%). Using the generic CLQI (scored 0-36), from the parental perspective the highest score was for AD (33%), followed by urticaria (28%), psoriasis (27%) and alopecia (19%). Comparing this with children with other chronic diseases, those with cerebral palsy had the highest score (38%), followed in descending order by those with generalized AD (33%), renal disease (33%), cystic fibrosis (32%), urticaria (28%), asthma (28%) and psoriasis (27%). Diseases such as epilepsy (24%) and enuresis (24%) scored higher than diabetes (19%), localized eczema (19%), alopecia (19%) and acne (16%).
Conclusions: Using the CLQI we have shown that HRQL impairment in children with chronic skin disease is at least equal to that experienced by children with many other chronic diseases of childhood, with AD and psoriasis having the greatest impact on HRQL among chronic skin disorders and only cerebral palsy scoring higher than AD. Cross-validation of the CLQI with the CDLQI in the group of children with skin disease demonstrates a strong linear association and good agreement between the two.