Preliminary reliability and validity of Persian version of the Family Dermatology Life Quality Index (FDLQI)

Purpose: Family Dermatology Life Quality Index (FDLQI) is an instrument for assessing the quality of life of family members of dermatologic patients. The aim of this study was to describe the cultural adaptation of this questionnaire and to assess psychometric properties of the Persian version. Methods: At first, the questionnaire was translated into Persian, and then back-translation was performed. The whole cycle was repeated until a consensus was reached about the optimal translation. In the next step, cognitive debriefing was performed, and after approval of the Persian version by FDLQI developers, it was distributed among 100 family members of dermatological patients in order to evaluate its validity and reliability. Results: Mean age of participants was 37.1 years (±12.3). Mean score of FDLQI was 15.4 (±5.5) with maximum and minimum scores of 30 and 6, respectively. The quality of life of studied participants showed no significant difference based on age-group, sex, educational level and the family relationship. Cronbach’s alpha was calculated as 0.87. Exploratory factor analysis revealed a one-factor solution that accounted for 40.7 % of the variance. The unidimensional model was supported by confirmatory factor analysis. Conclusions: The results of the present study showed that the Persian version of FDLQI has acceptable factorial validity and internal consistency reliability

Determining the minimal clinically important difference and responsiveness of the Dermatology Life Quality Index (DLQI): further data

Aims: To determine the minimal clinically important difference (MCID) of the Dermatology Life Quality Index (DLQI) and its responsiveness to change in inflammatory skin diseases. Methods: A longitudinal study: at stage 1, patients completed the DLQI and a disease severity global question; at stage 2, a global rating of change in quality of life (QoL; Global Rating of Change Questionnaire, GRCQ) was added and used as an anchor to measure the MCID of the DLQI. Results: 192 patients completed stage 1 and 107 completed stage 2. The mean DLQI score at stage 1 was 9.8 and 7.4 at stage 2 with a mean change of 2.4 (p < 0.0001). 31 patients experienced a ‘small change' in their QoL (±3 and ±2) on the GRCQ. The mean corresponding change in DLQI scores was 3.3, which is regarded as the approximate MCID. Conclusions: Previous estimates of the MCID of the DLQI have varied from 3 to 5. Although this study demonstrated a MCID of 3.3, we recommend that the MCID in inflammatory skin diseases should be 4

Clinical experience and psychometric properties of the Children's Dermatology Life Quality Index (CDLQI), 1995-2012

The Children's Dermatology Life Quality Index (CDLQI) is a widely used questionnaire to measure the quality of life of children aged from 4 to 16 years. The purpose of this review is to summarize all published data regarding the clinical experience of the CDLQI and its psychometric properties as a single reference source for potential users. A literature search was carried out to identify all articles describing the use of the CDLQI from 1995 to November 2012. One hundred and six articles were identified, with four excluded. The CDLQI has been used in 28 countries in 102 clinical studies and is available in 44 languages, including six cultural adaptations; a cartoon version is available in 10 languages. It has been used in 14 skin conditions and used in the assessment of 11 topical drugs, nine systemic drugs, 13 therapeutic interventions and two epidemiological and other studies. There is evidence of high internal consistency, test–retest reliability, responsiveness to change, and significant correlation with other subjective and objective measures. Rasch analysis has not been carried out and more information is needed concerning minimal clinically important difference; these are areas requiring further study