The UWI HARP is also responsible for continuous updating of the university's HIV/AIDS policy and for facilitating research on the impact and control of the epidemic in the region. Haiti is low income, for example, and Guyana is lower-middle income. Barbados, Belize, Dominica, Grenada, St Kitts and Nevis, St Lucia and Trinidad and Tobago are all defined as upper-middle income and yet vary greatly in their ability to invest national resources in public health. Table 4.5 shows the public health expenditure as a percentage of GDP for selected Caribbean countries.