Validation of a comprehensive Freiburg Life Quality Assessment (FLQA) core questionnaire and development of a threshold system.

Health related quality of life (HRQOL) has become an important re- search topic in dermatology. We developed a series of modular, dermatology-specific HRQOL questionnaires: the Freiburg Life Quality Assessment (FLQA). Each FLQA questionnaire consists of a core module (FLQA-c) applicable to all skin diseases plus a number of items specific to distinct dermatological diseases. The objectives of the present study were: 1) to test the psychometric properties of the FLQA-c, and 2) to define a threshold indicating a significantly reduced HRQOL. 394 psoriasis patients, 253 atopic dermatitis patients, and 240 control subjects completed the FLQA-c. Cronbach's alphas were above 0.75 for all six scales except for "treatment". Discriminant validity, sensitivity to change, and convergent validity were satisfactory. On the different scales, the threshold indicating a marked reduction in HRQOL detected 33% to 68% of the patients. These data support the reliability and validity of the FLQA-c. Copyright John Libbey Eurotext 2003.