Andrew Y. Finlay1, Sam S. Salek2 and Vincent Piguet1

1Department of Dermatology and Wound Healing, Institute of Infection and Immunity, Cardiff University School of Medicine, Heath Park, Cardiff CF14 4XN, and 2Department of Pharmacy, University of Hertfordshire, Hatfield and Institute for Medicines Development, Cardiff, UK. E-mail: FinlayAY@cf.ac.uk

Sir,

The articles by Amer et al. (1) and Boccara et al. (2) both focus on the impact of skin disease on the lives of other family members, the “Greater Patient” (3). This secondary impact of skin disease may be very extensive (3–5) and deserves wider study and understanding.

Amer et al. (1) used the Dermatitis Family Index (DFI) in their study of childhood vitiligo: however the DFI was created (4) and has been validated (5) only for use in families of children with atopic eczema, as suggested by its name. As noted in our review of the use of the DFI (5) several other authors have previously also used the DFI inappropriately for diagnoses other than atopic eczema. The need for a measure that could be used in families affected by other skin diseases led us to develop (6) and validate (7) the Family Dermatology Life Quality Index (FDLQI).

Investigators should only use disease specific measures for the specific disease for which the measure has been validated: such as the DFI (4) when studying atopic dermatitis or the Psoriasis Family Index (PFI-14) (8) when studying psoriasis. The use of the FDLQI (6, 9) should be considered where a dermatology specific family quality of life (QoL) measure is required. The FDLQI has been used to measure the impact of vitiligo on the QoL of family members (10).

The concept of Family Burden of skin disease (2) is a useful development: it would be of interest to cross-validate the disease specific Hemangioma Family Burden questionnaire with the generic FDLQI.  

With the growing awareness and study of the family impact of skin diseases (11), it will be useful to compare the impact of skin diseases on the partner and other family members with the impact of other non-skin diseases (12). This is now possible using the generic Family Reported Outcome Measure (FROM-16) (13). This 16-question tool was created and validated with information from 26 specialties, including dermatology (14). The FROM-16 can be used in parallel with a dermatology or disease specific family measure.

Conflict of interest: AYF is joint copyright owner of the DFI, FDLQI, PFI-14 and FROM-16. SS is joint copyright owner of the PFI-14 and FROM-16.

The authors of the original articles (Amer and Boccara) were given the opportunity to comment in response to this Letter, but chose not to do so.

References