International pilot tests of the epidermolysis bullosa-specific module of the Infants and Toddlers Dermatology Quality of Life questionnaire

Responsiveness and Minimal Clinically Important Difference of the Infants and Toddlers Dermatology Quality of Life Questionnaire

BACKGROUND

The Infants and Toddlers Dermatology Quality of Life (InToDermQoL) is the dermatology-specific proxy health-related quality of life (HRQoL) instrument for children from birth to 4 years. The aim of the present study was to confirm the responsiveness and establish minimal clinically important difference (MCID) for the InToDermQoL.

METHODS

Parents of children with skin diseases were asked to fill in the InToDermQoL at the initial visit (T1) and subsequent consultation (T2). We hypothesized that correlations between change scores of the InToDermQoL and change scores of global assessment of clinical severity by dermatologists and by patients' parents should be above 0.3. The receiver operating characteristic (ROC) curves method was also used for confirmation of responsiveness and determination of MCIDs of the InToDermQoL. The area under the ROC curve (AUC) was used as an indicator of responsiveness.

RESULTS

Results of 442 patients were included. Correlations between change scores of age-specific versions of the InToDermQoL and change scores of global assessment of clinical severity by dermatologists and by patients' parents were above 0.3 (0.46-0.74). AUCs for age-specific versions of the InToDermQoL were acceptable (above 0.7) or excellent (above 0.8). Estimated MCIDs for the InToDermQoL were as follows: 3 points of total score change for 0-11 months, 5 for 1-2 years and 3 or 4 for 3-4 years version. Estimated MCIDs for the InToDermQoL version for 1-2-year-old children was higher than MCIDs for the 3-4-year-old version despite the higher number of items in the latter. Therefore a MCID of 5 was recommended for both these versions.

CONCLUSIONS

Responsiveness for all age-specific versions of the InToDermQoL questionnaire was confirmed. MCIDs for the InToDermQoL are proposed as follows: 3-point change of the total score for age version 0-11 months and 5-point for the age versions 1-2 years and 3-4 years.

Sensitivity to treatment and score bands of the Infants and Toddlers Dermatology Quality of Life questionnaire

Background

The Infants and Toddlers Dermatology Quality of Life (InToDermQoL) questionnaire is the first dermatology-specific proxy health related QoL instrument for children from birth to 4 years. Score meaning bands and the sensitivity to successful therapeutic intervention are important to interpret the clinical meaning of an instrument.

Objective

The aim of the present study was to check the sensitivity to successful therapeutic intervention and establish score bands of the InToDermQoL questionnaire.

Methods

Parents or grandparents of 424 children with skin diseases from Spain, Malta, Croatia, Romania, Greece, and Ukraine filled in national language versions of the InToDermQoL questionnaire. Disease severity of children with atopic dermatitis was assessed by SCORAD (Scoring atopic dermatitis). Cohen's d was used to assess the responsiveness of the instrument.

Results

The mean total InToDermQoL scores significantly decreased after treatment. Severity grading of the SCORAD scores gave stratification of the InToDermQoL severity grades based on 95% confidence intervals. Scores below a calculated minimal important difference of 2 corresponded to no effect on patient's health related QoL.

Limitations

Score banding may be slightly different across patient population and study context.

Conclusion

All 3 age-specific versions of the InToDermQoL questionnaire showed sensitivity to treatment. Score bands for the InToDermQoL questionnaire have been established.

Initial validation of the epidermolysis bullosa-specific module of the Infants and Toddlers Dermatology Quality of Life questionnaire

Children with epidermolysis bullosa (EB) experienced the highest quality of life impact among several skin conditions and have problems which had not been reported by parents of children with other skin diseases. The EB-specific module of the Infants and Toddlers Dermatology Quality of Life (InToDermQoL) questionnaire was recently developed to measure the impact of disease-specific aspects in children from birth to the age of 4 years. The aim of this study was initial validation of the InToDermQoL-EB questionnaire. Parents of 44 children with EB from seven countries completed the InToDermQoL-EB questionnaire. Cronbach's alpha was .86, .89 and .91 for three age-specific versions. Differences between severity levels were all significant except for that between moderate and severe level in the version for 3- to 4-year-old children. All items of the three versions of the InToDermQoL-EB showed very high levels of relevance except "problems with defecation" in children younger than 1 year and "rejection by other children" in 3- to 4-year-old children. The three versions of the InToDermQoL-EB instrument showed good internal consistency and discriminated well between different severity levels. All InToDermQoL-EB items were confirmed as being of high relevance and the questionnaire may be used in practice and clinical trials.