The EDQLS: A New Instrument for Measuring Quality of Life
By Carol Adair, PhD, Gisele Marcoux, PhD, and
Marlene Reimer, PhD
Reprinted from Eating Disorders Review
November/December 2005 Volume 16, Number 6
©2005 Gürze Books
Quality of life (QOL) is increasingly being recognized as an important outcome of treatment, yet eating disorders outcome measurement has often focused on reduction of symptoms rather than on functioning or quality of life. This may be caused by the fact that until recently no suitable instrument for measuring QOL has been available for people with eating disorders.
Where QOL has been measured, reports from clinicians suggest that generic QOL instruments developed for other (typically adult) patient populations seem to lack relevance (i.e., questionnaire items fail to reflect the developmental issues of adolescents and young adults), and patient response has also been found to be poor.
A new QOL Instrument
Our group has developed and piloted a new QOL instrument – the Eating Disorders Quality of Life Scale (EDQLS), in collaboration with eating disorder professionals at five other sites. The EDQLS addresses areas that reflect aspects of life that are affected by eating disorders and that are likely to change with recovery (for example, leisure interests or relationships). It is written in age-appropriate language and covers content of relevance to adolescents and young adults with eating disorders. Preliminary results suggest that it may be very useful in guiding individual treatment, evaluating services, and researching new treatments.
An initial pool of about 300 items was generated using extraction of QOL themes from the eating disorders literature, from patient and interviews with eating disorders professionals, and from first-person narratives from the Internet.* The initial domains and items were validated in focus groups with patients, and then systematically pre-tested by patients, eating disorder professionals, and family members.
Four qualifying factors
To be retained in the questionnaire initially selected items had to be rated highly on four principles:
- Directionality (the item was capable of showing change in a linear direction with treatment);
- Universality (the item captured behaviors or feelings across different types of eating disorders and across the range of ages of patients with eating disorders);
- Wording/Ambiguity (the item was clearly worded and understood without varying interpretations), and
- General Likeability (the item had resonance and general face validity).
Several stages of testing and refinement resulted in a final set of 40 items in the following 12 domains: cognitive functioning, education/vocation, family and close relationships, relationships with others, future/outlook, appearance, leisure, psychological health, emotional health, values and beliefs, physical health and eating issues. The EDQLS takes an average five minutes to complete and has undergone initial testing in individuals with eating disorders who are as young as 14 and as old as 44 years of age. Its reading level is measured at grades 5 to 7.
Pilot results are encouraging and were presented on November 28-30, 2005 at a conference in Banff, Alberta, Canada. Results have also been submitted for publication and for presentation at the International Eating Disorders Conference, to be held in Barcelona in June 2006. In addition, a field test and validation study is underway in 10 eating disorder clinics across Canada.
While the EDQLS will not be ready for general use until after results of field testing are in (expected mid-2006), eating disorder professionals are invited to provide their expert impressions on the face validity of the new instrument.
*Some of the early developmental work is currently in press in Qualitative Health Research.