Classification of quality of life subscales within the ICF framework in burn research: Identifying overlaps and gaps

Abstract

Objective

Quality of life (QOL) is one of the leading outcomes in burn care research. This study classifies subscales of common QOL measures within the International Classification of Functioning disability and health (ICF) framework to determine to which extent the measures are complementary or overlapping and to investigate whether the instruments are able to describe the full spectrum of patients’ functioning.

Methods

A literature search was performed to determine the most frequently used questionnaires in burn research. The subscales of the three mostly used questionnaires were classified within the ICF framework.

Results

Two generic measures, the Short Form-36 items (SF-36) and the European Quality of Life 5 Dimensions (EQ-5D), and a disease specific measure, the Burn Specific Health Scale-Brief (BSHS-B), were analyzed. The BSHS-B covered most domains and was the only scale that included personal factors. The SF-36 included only one domain in the activity limitations and similar to the EQ-5D no contextual factors were included. Environmental factors were not addressed in the questionnaires, even though these may have an impact on the quality of life in patients with burns.

Conclusion

To capture the full spectrum of dysfunctioning a combination of the BSHS-B with a generic questionnaire seems obligatory. However still some domains of functioning remain uncovered.

Introduction

Two decades ago, the World Health Organization (WHO) defined quality of life (QOL) as “an individual's perception of their position in life in the context of the culture and value systems in which they live and in relation to their goals, expectations, standards and concerns. It is a broad ranging concept affected in a complex way by the person's physical health, psychological state, personal beliefs, social relationships and their relationship to salient features of their environment” [1], [2]. Since then, QOL has received increasing attention, including in burn populations, and a burgeoning body of research documented burn survivors’ health-related quality of life (HRQOL) [3], [4], [5], [6], [7].

In burn research various generic HRQOL self-report measures have been used. The most common burn specific questionnaire available is the Burn Specific Health Scale (BSHS) that has a long history of several adaptations [4], [8], [9]. The most frequently used version in recent years is the Burn Specific Health Scale Brief (BSHS-B) that has been translated in several languages all over the world [4], [10]. The BSHS-B has been shown to be measurement invariant across two European countries, indicating its stability across cultures [11]. However, it is currently unclear to which extent the BSHS-B and generic HRQOL measures are complementary or overlapping in measuring different aspects of HRQOL following burns and whether the full spectrum of disability is captured by using (a combination of the) questionnaires.

To elucidate which HRQOL aspects are covered by the currently used self-report measures a broad bio-psycho-social framework is of interest. The International Classification of Functioning Disability and Health (ICF) is a worldwide used framework to describe the health condition of a patient in such a context. The ICF inventories all domains of disability from body, individual and societal perspectives [12]. As presented in Fig. 1, disability involves dysfunctioning at one or more of these levels: impairments in body function or structures, activity limitations and participation restrictions. The environmental factors (physical and social environment) and the personal factors, such as age, gender and marital status, may influence human functioning in a positive or negative manner. In sum, the ICF enables the understanding of phenomena related to function that may be particularly relevant when assessing quality of life following burns.

Despite the growing attention for functional outcome during the last fifteen years in burn research the limited application of HRQOL measures within the ICF framework is notable with very few burn articles on this subject [12], [13]. One review on functional outcome identified seven core domains that were considered essential to comprehensively assess outcome after burns [15]. The core domains proposed are skin, neuromuscular function, sensory and pain, psychological function, physical role function, community participation and perceived quality of life, but it is unclear to which extent the proposed domains are captured in the most commonly used self-report measures. In a systematic review concepts of common outcome measures in burn care were considered within the ICF framework using standardized linking rules. HRQOL questionnaires were included in this study and it was reported that 43 concepts (out of 50) of the BSHS-B could be linked to the ICF [14]. In clinical practice, however, the interpretation of the outcome is often based on the subscale scores of the questionnaires, rather than interpreting the distinct items. Currently, no reports are available linking the subscales of the HRQOL questionnaires to the ICF framework in an attempt to describe functioning following burns.

The aim of this study is to classify the subscales of frequently used HRQOL measures within the ICF and to answer the question if these instruments are able to describe the broad spectrum of patients’ functioning. Moreover this paper seeks to address the following questions: What aspects of HRQOL do the different questionnaires measure? What aspects of HRQOL are left uncovered? Which different domains of ICF are covered by each questionnaire?