There exists no single definition of disability. The multidimensionality of disability demands that more complex, flexible measures that will capture disability in all its manifestations be developed and adapted. The measurement of disability prevalence must be seen in light of the purpose that these data are collected for example, provision of services, assessment of the level of functioning in the population or equalisation of opportunities and inclusion of people with disabilities in society. Any reported disability prevalence rate is dependent both on the definition or aspect of disability that is being targeted and on the intended purpose for collecting disability statistics.

Results from a national, representative survey of living conditions among people with disabilities in Zambia based, in part, on the work of the Washington Group on Disability Statistics (WG) that operationalises a functional approach to disability are presented and contrasted with historical census data to illustrate how a flexible approach to the measurement of disability is better suited to the multiple purposes of collecting disability statistics and to the diversity of disability in a population.