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Notes: Background  Atopic dermatitis (AD) is a chronic or chronically relapsing inflammatory skin condition that can have a considerable impact on those affected. There are a number of instruments available to measure outcome in dermatological conditions but none have been developed specifically for AD. In addition, most measure symptoms and/or daily functioning, which are potential influences on quality of life (QoL) rather than assessments of the construct itself.Objectives  The aim of the current study was to develop a new instrument specifically designed to measure QoL in adults with AD—the Quality of Life Index for Atopic Dermatitis (QoLIAD).Methods  The instrument was developed based on the needs-based model of QoL and was produced in several different countries simultaneously. Its content was derived from 65 in-depth interviews with relevant patients in the U.K., Italy and the Netherlands. The initial version of the measure was produced in U.K. English and translations were produced for the Netherlands, Italy, Germany, France and the U.S.A. using a dual translation panel methodology. A Spanish version was developed using the same adaptation process after the instrument was finalized. Field-test interviews were conducted with approximately 20 patients in each country to assess face and content validity. The instrument [in addition to the Dermatology Life Quality Index (DLQI) and the Psychological General Well-Being Schedule (PGWB)] was then administered to up to 300 AD patients in each country at two time points to finalize the instrument and test its psychometric properties.Results  The initial version of the QoLIAD had 56 items that reflected the areas of need fulfilment identified in the qualitative interviews as having been affected by AD: mental and emotional stimulation, physical and emotional stability, security, sharing and belonging, self-esteem, personal development and fulfilment. Comments from patients in field-test interviews resulted in the removal of 14 items, to leave a 42-item instrument that was considered relevant and acceptable. The number of patients participating in the survey were 286 in the U.K., 46 in the Netherlands, 213 in France, 187 in Germany, 178 in the U.S.A. and 83 in Spain. Application of the Rasch model to these data identified the final 25-item QoLIAD. Unidimensionality was confirmed, with deviation of the total scale from the Rasch model evident at a single time point in one country only (the U.K.). All language versions, with the exception of the Dutch measure, had test–retest reliability coefficients in excess of 0·85. The test–retest in the Netherlands was 0·80. However, this country had the smallest sample size and the corresponding reliability for the DLQI was only 0·40. The QoLIAD had adequate internal consistency and the initial indications of construct validity were good. The levels of association with the DLQI indicated that the two instruments measure related but distinct constructs.Conclusions  The QoLIAD is a practical, reliable, valid and culturally applicable instrument for measuring the impact of AD and its treatment on QoL in clinical trials or in routine clinical practice.

Notes: Abstract This paper describes the international development and psychometric testing of the Recurrent Genital Herpes Quality of Life Questionnaire (RGHQoL), a condition-specific quality of life (QoL) instrument. The theoretical foundation for the measure is the needs-based model of QoL and the content of the instrument was derived from in-depth qualitative interviews with relevant patients in the UK. Versions of the RGHQoL were required for the UK, USA, Italy, Germany, France and Denmark for use in international clinical trials. The results indicate that the final 20 item measure has good reliability, internal consistency and validity for all language versions. A small responsiveness study in Denmark suggested that the measure is sensitive to changes in QoL associated with the initiation of suppression treatment for recurrent genital herpes (RGH). It is concluded that the RGHQoL is a valuable instrument for inclusion in clinical trials. The psychometric properties of the instrument are such that it may also be used to monitor the progress of individual patients.