Think before you measure

“Think before you measure” was the theme of a symposium held in Sydney, Australia, in June 2011. Selected papers based on the symposium comprise this special issue. The symposium was held alongside meetings of two committees of the World Health Organization Family of International Classifications (WHO-FIC) Network, whose role is to foster the development and application of international health classifications, with the vision that classifications form “the building blocks” of information infrastructure and systems [1]. Accordingly, classifications are facilitators of the thought that is seen as essential before proceeding toward measurement; many of the papers in this special issue reflect this consciousness, with focus on the International Classification of Functioning, Disability and Health (ICF) [2]. Classifications are themselves shaped by knowledge and thought and, in their application, further shape ensuing research and knowledge gained. As Judith Hollenweger elegantly explains: “Classifications are representations of a knowledge domain but at the same time also guide knowledge creation”.

Readers of this journal will be most familiar with discussions on the use of the ICF in the rehabilitation field. The World Report on Disability defined rehabilitation as a “set of measures that assist individuals who experience, or are likely to experience, disability to achieve and maintain optimal functioning in interaction with their environments” [3]: [page 96]. Gerold Stucki some years ago pointed to the relevance of the ICF not only directly in the rehabilitation clinic—for instance in monitoring the functioning status of patients—but also more broadly, describing the ICF as “a unifying framework and classification for physical medicine and rehabilitation” [4]. He and colleagues have developed a range of health condition-specific “ICF Core Sets” to facilitate the use of the ICF in clinical practice and specifically in rehabilitation [5,6] as well as in vocational rehabilitation [7]. In this issue, several authors expand on the idea of the ICF as a unifying framework and the symposium theme in a variety of ways. Kellett et al. illustrate how the ICF can be used, during patient consultations, as part of a framework for planning patient goals and treatments. The approach is described as a prototype of a “clinical tool … designed iteratively using reflection-on-knowledge, reflection-in-action and reflection-on-action in rehabilitation medicine practice”. The framework encourages the clinician to think beyond the immediate treatment program to relate it to the person’s long-term goals and environment. This approach then contributes to improved, structured clinical reporting to patients and to other stakeholders including referring practitioners. Mpofu points to the use of “life design” counseling in rehabilitation assessment and the need for “careful consideration of the source, type, and scope of these data … in selecting appropriate procedures for their collection and use.” He suggests that “effective life design” with people with chronic illness or disability “is enhanced with person-centric, resource enabling and participation focused data.” Martinuzzi et al. report on an institution-wide ICF application—the introduction of an ICF-CY based form for rehabilitation programming in a paediatric neuro-rehabilitation hospital. The implementation of this form enabled the linking of problems in functioning, objectives, rehabilitation activities, and outcome indicators. It was reported that no additional resources were needed for its implementation. The ICF-based program was appreciated by both team members and caregivers as adding quality to the rehabilitation process. Overall the results confirmed the feasibility of the approach and were considered to encourage the implementation of ICF based tools in the clinical sector.

The particular contribution of this special issue is the thoughtful attention given to the promise of the ICF, now being realised, as a systematic framework and a common language for functioning in many contexts. The versatility of the ICF is apparent, for instance, in its use in population studies. Population survey data provide essential understanding of population health and functioning—information available to and used by policy makers, health and other professionals, and the community at large. There are considerable national and international efforts to ensure that the ICF framework informs survey data collections, and a number of key initiatives are outlined in two papers in this issue. The World Report on Disability published new estimates for the prevalence of disability across the world [3]; 15% of the world’s population experience significant difficulty with functioning and some 2% “severe or extreme difficulties”. Kostanjsek et al. describe the processes for calculating these estimates and the challenges which had to be overcome—and those which require ongoing effort among statisticians and researchers, including “more work on the various approaches for setting thresholds that are fit for purpose”. The ICF framework informed the estimates and also enabled the understanding of spurious differences in international comparisons, arising chiefly from the use of varying concepts of disability and different domains of functioning in national surveys. The same paper describes the design of a new national survey in Ireland, based directly on the ICF (rather than being retro-fitted to it). A major advantage was the inclusion of the ICF’s Environmental Factors component, yielding new information relevant to monitoring the United Nations (UN) Convention on the Rights of Persons with Disabilities. For example, participation of people with disabilities in Irish society was found to be significantly affected by attitudes, the presence or absence of facilitating equipment, support services, flexible working arrangements and transport. The ICF is not only a world standard, but also a common language to enable comparable data to be collected [2]. Madans and Loeb outline the important work, over a decade or more, of the Washington Group (a UN Statistical Commission sponsored city group), to develop population census and survey questions for use worldwide, that will promote comparable disability statistics. The survey development work described in these two papers should be of significant interest to clinicians and other professionals—not only for the data yielded, but also for the new tools and questions being developed.

No less exciting is a range of other initiatives bringing the ICF perspective to broader policy arenas, with the aim of enhancing policy and administration, and improving outcomes for people. Richard Madden et al. focus on health system financing where casemix models, for funding activity in health care and assessing performance, depend on data based on uniformity of resource utilisation; diagnosis-related groups have been used for this purpose for years in many countries. However, the authors note that “it has long been an ideal to relate the measure of value more to patient outcome than output”. Their paper explores the potential for further development of casemix systems to include functioning domains. They suggest that the WHO-FIC—chiefly the International Classification of Diseases (ICD), the ICF and the International Classification of Health Interventions (being developed)—provides a “structured set of domains for health conditions, interventions and functioning that can be systematically explored to seek improved discrimination among health episodes for case mix analysis and funding purposes.” Tongsiri and Riewpaiboon explore the possibility of sampling from a disability registration data base in a Thai province, and then surveying the people sampled using questions based on ICF categories and qualifiers. Outlining their experience and results, they propose this method to assist in service planning and environmental improvements for people with disabilities. Judith Hollenweger extends our scope even wider, into the field of education. The ICF is used in Switzerland as a system-wide framework, a common language for multiple stakeholders at different “levels” in the system, and a foundation on which to build processes that develop “shared actionable knowledge”. An ICF-based tool is used to “organise collaborative assessment and planning meetings”. The ICF is used to “help organise and clarify information generated by different persons’ (page refs in this issue?). Hollenweger’s paper paints a careful picture of these processes, the roles of the multiple stakeholders involved, and how they may contribute “context-free information, context-specific information and context-dependent information”.

Some common themes in the process of thinking before recording or measuring functioning emerge from this body of papers. Ros Madden et al. draw together the main elements of such reflection under the simple headings: why (purpose), what (content relevant to purpose), how and when (method) and who (source). The UN Convention on the Rights of Persons with Disabilities sets out the moral and legal framework for the field and indicates its broad scope and over-arching purpose. The ICF provides the corresponding technical framework and we now know more about how to use it. For instance, based on different but confirmatory analyses, Kostanjsek et al. and Ros Madden et al. emphasise the importance of seeking information on a broad range of functioning domains—in deciding “what” to record or measure, all functioning domains should be considered in diverse populations (e.g. [7]). There are specific challenges in functioning and disability measurement methods: for instance the reasoned setting of thresholds on disability continua may be informed by the understanding of multiple potential purposes (for instance in population surveys) or by more singular purposes (most policy settings). The dearth of approaches which integrate the Environmental Factors component of the ICF into the measurement of functioning and disability is emphasised by Kostanjsek et al. and Ros Madden et al., who note the need for research which will “contribute to an epidemiology of disability, enlarging on the traditional focus of epidemiology on health conditions.”

The question of “whose measurement” is highly topical in a number of fields and requires future work (Hollenweger and Ros Madden et al.). Hollenweger’s account of the process of developing “shared actionable knowledge” among multiple stakeholders provides a beacon lighting the way forward in this broad field: “Meaningful decision-making in complex social situations needs to rely on all relevant knowledge distributed across different people, often representing different perspectives and interests.” The question of how multiple observations can be respectfully and validly combined during decision-making processes entails work of methodological rigor and the ethical standards required by the ICF and the UN Convention on the Rights of Persons with Disabilities.

Participants in the Think Before You Measure symposium, in tune with Hollenweger’s statement, contributed significantly to reflection about the measurement of human functioning, with relevant knowledge and different perspectives and interests. The papers in this special issue will, we trust, stimulate further discussion and development.

Acknowledgments

The authors, as guest editors of this special issue, sincerely thank Imelda Noti (University of Sydney) for thoughtful and meticulous editorial assistance throughout 2012, and likewise Tinashe Dune until December 2011.

Declaration of Interest: The authors report no declarations of interest.