Quality of life evaluation in wounds: validation of the Freiburg Life Quality Assessment-wound module, a disease-specific instrument.

Many patients with chronic wounds suffer not only directly from their wounds but also from high financial, social and psychological impairments, significantly reducing their quality of life. In order to provide an instrument both applicable to different patient populations and sensitive to areas of impact specific to certain skin diseases, the modular instrument 'Freiburg Life Quality Assessment' has been developed. Each disease-specific version of the instrument consists of a core module of generic items and items specific for a distinct skin disease. Objective of the study was to assess reliability, sensitivity to change, and validity of the module for chronic ulcers. The instrument was implemented in a longitudinal observational study on vacuum-seal therapy (n = 175), in a cross-sectional observational study involving patients with chronic leg ulcers (n = 384) and in a randomised clinical trial on keratinocyte transplantation (n = 198). The instrument showed good internal consistency (Cronbach's alpha ≥0·85). There were minor floor effects ≤4·3%, but no ceiling effects. Retest-reliability and convergent validity with the EuroQol quality of life questionnaire (EQ-5D) (visual analogue scale) were satisfactory. Change scores correlated with change in other quality-of-life instruments (r = 0·59-0·61), but not with change in wound status.