The rising average age of the world’s population presents an opportunity to rethink health policy. In February 2024, the National Academies convened a hybrid workshop at the University of Lucerne in Switzerland to host a discussion focused on the World Health Organization's concept of functioning and how it could impact overall health with an emphasis on healthy aging and rehabilitation. This new interactive resource summarizes content from the workshop, where participants offered suggestions to operationalize functioning as a health policy measure, rethink disability as a universal human experience, formulate a feasible public health agenda that addresses the increasing relevance of rehabilitation, and more.
Focus Areas
Functioning and Rehabilitation for Healthy Longevity
Workshop participants discussed how both functioning and rehabilitation are key factors in healthy aging, improved quality of life, and the prevention of and recovery from illness and injury across the lifespan. As such, functioning should be added as another dimension of health, beyond measures of mortality and morbidity (Bickenbach). There are various tools that aid in integrating functioning across health systems (Gimigliano), and several strategies that can advance the measurement of functioning and how assessment tools can help practitioners, such as giving equal weight to measures of success in functional tests and including more nuanced data in evaluating interventions (Beard, Prodinger, Simonsick). Importantly, considering what matters most to older adults and moving beyond the minimum level of ability or expectation of such are crucial to countering ageism and focusing on only addressing existing limitations (Bean, Beard, Katz, Keith, Simonsick).
Functioning as the Foundation for Healthy Longevity Research
Workshop participants discussed strategies to support healthy longevity research, including developing hybrid assessment tools that combine self-reporting and clinical assessments. A primary topic of discussion was WHO’s ICF system. The ICF system could be used to establish comparability among measures for functioning (Sillitti, Willers); standardize reporting and data collection on functioning in health systems (Bean, Engkasan, Gimigliano, Prodinger, Reinhardt); assist in defining improved outcomes from rehabilitation in the context of research (Beard, Bickenbach, Reinhardt); serve as a context for understanding functioning’s importance in health care delivery and policy (Gimigliano, Hajjioui, Reinhardt); and consider its applicability to aging (Bean, Beard). Implementation research can shed light on intervention efficacy and how interventions should be packaged (Bean). Functioning-based health research could also benefit from developing and using assessment tools or frameworks like WHO’s Integrated Care for Older People model, which uses both patient-reported data and measurements taken by clinicians (Morsch).
Advocating for Policies that Support Healthy Longevity, Rehabilitation, and Functioning
Workshop participants discussed how advocating for policy change will require engagement from partners in multiple sectors, including user-led organizations (Hajjioui, Katz). Collaboration across and with health care systems, clinician and patient groups, and content experts is critical (Jette). Reframing advocacy efforts to focus on rehabilitation as an investment to improve functioning rather than just another health expense is also important (Gimigliano). Survey measurement tools and economic research must be strengthened to address measurement gaps that may impact functioning advocacy efforts (Boggs). Improved education about functioning and curricula on conducting and disseminating research for practicing clinicians and those involved in human functioning sciences are needed to train researchers in best practices (Engkasan, Hajjioui, Reinhardt) and all approaches should emphasize community engagement across a variety of settings (Morsch). Ageism must also be addressed, while simultaneously recognizing the value that older adults contribute to their communities outside of the formal workforce, as well as ensuring that older adults’ goals inform policies (Beard, Katz, Keith).
Making a Compelling Investment Case for Optimizing Functioning and Supporting Rehabilitation Health Services as a Strategy for All People
Workshop participants highlighted the importance of using return-on-investment and cost-effectiveness studies to build the economic case for investing in functioning and rehabilitation and called for reframing rehabilitation as an investment in improving functioning (Gimigliano, Sillitti, Willers). Workshop participants believe that investing in rehabilitation will reduce the need for acute and long-term care (Sillitti), but more evidence is needed to support the economic case and illustrate the overall return on investment (Boggs, Gimigliano, Sillitti, Willers). Developing better measures of functioning will be key for making a compelling investment case—for example, although DALYs can help quantify the burden of disease, the measure is disconnected from how researchers and clinicians define disability (Reinhardt). Fully supporting functioning will also require coordination between services across the lifespan (Leonardi). Strategies to support addressing functioning comprehensively include adopting new technologies that detect or potentially delay the onset of conditions that impair functioning and integrating rehabilitation in multiple aspects of health systems and communities (Beard, Cieza, Frontera, Jette, Katz, Morsch, Mpofu).
The workshop concluded with the participants discussing final thoughts, challenges, and opportunities for the field of functioning, rehabilitation, and aging. Barriers to true integration of functioning across the lifespan exist, including too much focus on proxy measures, a bias toward simplistic measures of complex issues, and inadequate cross-sector collaboration (Bickenbach). Making human functioning sciences a distinct discipline would help shift the current medical focus away from assessing a person by their disease, condition, or disability, and echoed several participants’ support for the ICF model as a foundation for improved measurement tools (Beard). The field will have to resolve the tension between improving functioning as a public health strategy and deploying rehabilitation as a clinical treatment strategy, because the two can complement and strengthen each other, while benefiting everyone (Cieza).