Development of this established clinical assessment tool leads to increased global reach and applications, and increases overall patient quality of life.

On a global level, dermatological conditions can cause suffering to the patient and poor quality of life. In the UK alone, skin conditions such as eczema, psoriasis and atopic dermatitis affect around 60% of the adult population at some point in their lifetime. These conditions can severely impact quality-of-life, as well as overall patient wellbeing.

The Dermatology Life Quality Index (DLQI) is a clinical assessment tool, developed by researchers at Cardiff University via research published in 1994. The simple-to-use questionnaire asks patients to describe the impact of their skin disease on different aspects of their health-related quality-of-life over the previous week. Before this research, no standard method was used to assess the impact of skin diseases on patient wellbeing.

New research enhancing global reach and clinical applicability

Since 2014 a Cardiff University team lead by Professor Andrew Finlay undertook additional extensive research, in order to enhance the use of the DLQI in clinical settings, broaden its global reach and increase the variety of clinical applications, including into clinical trials and drug development studies.

The university team refined the interpretation of the DLQI’s Minimal Clinically Important Difference (MCID) score, which can determine what kind of response a patient has to therapy or signal a need to alter patient management. This refinement altered the MCID from 5 to 4, which improved the DLQI’s validity, reliability and interpretation of change.

It had also been noted that clinicians had been using non-validated electronic versions of the DLQI, as patient-reported measures are increasingly being made in electronic format.

In a study of patients from a hospital dermatology outpatient clinic the university team validated the digital delivery and completion of the DLQI on iPads, providing opportunities for real-time monitoring of quality-of-life and an easier transfer of data to patient records.

Linking the DLQI to health utility estimates

Health utility estimates provide a measure of a patient’s preference for a given health-related outcome. Previously it wasn’t possible to calculate health utility values from the DLQI. Instead, a different instrument, such as the European Quality of Life-5 Dimension (EQ-5D) score, was required.

The university team developed a new method to calculate EQ-5D data and utility values from DLQI scores, simplifying the process for clinicians and patients.

The new validated method means that DLQI data can be mapped onto health utility measures, which can then be used in economic analyses, increasing the value of DLQI data and improving the identification of meaningful changes in quality of life for patients.