Theoretical foundations for the measurement of environmental factors and their impact on participation among people with disabilities.

The ascendance of the World Health Organization's International Classification of Functioning, Disability and Heath (ICF) as the global standard for describing and characterizing aspects of disability has refocused attention on the role that environmental factors (EFs) have on the health and participation of people with disabilities, both as individuals and as a group. There has been a rise in the development of instruments designed to measure EFs alone and in relation to participation. Some instrument developers have used the ICF as a theoretical base for instrument development and to substantiate content validity claims. We contend that this is a misapplication of the ICF. There is a need to step back and reexamine the role that environmental theories can play in developing a conceptually driven approach to measuring the interaction between EFs and participation. For this review, we draw on the fields of social, community, and developmental psychology; disability studies; gerontology; public health; and rehabilitation. We discuss different approaches to the measurement of EFs. We suggest that given the complex nature of EFs and their influence on participation, there is a need for a fresh approach to EF measurement. The thoughtful application of theories and the use of advanced psychometric, measurement, and e-technologies and data visualization methods may enable researchers and clinicians to better quantify, document, and communicate the dynamic interrelationship between EFs and participation and health outcomes for people with disabilities at the individual, group, and population levels.