Table 1.

AP access indicators definitions and calculations

AP access indicator	Working definition	Equation
Need	The proportion of a defined population who could benefit from using an appropriate AP, based on an AP assessment approach, including those already using the AP	Population who could benefit from an AP/defined population
Has AP	The proportion of a defined population who have an AP (obtained through purchase, loan, rent, donation or by other means)	Population who have APs/defined population
Use	The proportion of a defined population who use an AP	Population who use APs/defined population
Met need (population with full coverage)	The proportion of a population who need and use appropriate APs	Population who need and use appropriate APs/defined population
Undermet need (population with partial coverage)	The proportion of a population who need and use APs that are insufficient to maximise functioning	Population who use insufficient APs/defined population
Unmet need (population with no coverage)	The proportion of a population who need and do not use any APs	Population who need and do not use appropriate APs/defined population
Coverage	The proportion of a defined population who need and use an AP	Population who need and use APs/population who need APs

AP, assistive product.