Fragrance allergy and quality of life - development and validation of a disease-specific quality of life instrument.

Background: Fragrance allergy is a lifelong condition that may give rise to permanent or recurrent contact dermatitis and may affect quality of life (QoL). The effect on QoL has not yet been investigated, and no disease-specific QoL instrument for fragrance allergy exists.

Objective: To develop and validate a disease-specific instrument to investigate QoL among fragrance-allergic subjects.

Method: A fragrance QoL instrument (FQL index) was developed on the basis of narratives from 68 fragrance-allergic subjects, and consisted of 13 items. It was tested in a postal survey among 1650 participants patch tested at Gentofte University Hospital (2000–2010). The survey included other QoL instruments [Dermatology Life Quality Index (DLQI) and Short Form 36 (SF36) version 2] and questions on eczema severity (response rate of 66%). A retest was conducted after 3–6 months (response rate of 72.5%).

Results: The FQL index showed a significant and strong correlation with the DLQI (rS = 0.70), and disease severity, but a weak correlation with SF36 [mental component summary score, rS = − 0.22; physical component summary score, rS = − 0.31]. Good reliability and responsiveness to changes in disease severity were seen.

Conclusion: The FQL index is a good instrument with which to investigate QoL in subjects with fragrance allergy. Good correlations with the DLQI and self-estimated disease severity were seen, and it showed good reliability, reproducibility and ability to distinguish changes in disease severity.