  South Africa's disability grants program is tied to its HIV/AIDS recovery
program, such that individuals who are ill enough may qualify. Qualification is
historically tied to a CD4 count of 200 cells/mm3, which improve when a person
adheres to antiretroviral therapy. This creates a potential unintended
consequence where poor individuals, faced with potential loss of their income,
may choose to limit their recovery through non-adherence. To test for
manipulation caused by grant rules, we identify differences in disability grant
recipients and non-recipients' rate of CD4 recovery around the qualification
threshold, implemented as a fixed-effects difference-in-difference around the
threshold. We use data from the Africa Health Research Institute Demographic
and Health Surveillance System (AHRI DSS) in rural KwaZulu-Natal, South Africa,
utilizing DG status and laboratory CD4 count records for 8,497 individuals to
test whether there are any systematic differences in CD4 recover rates among
eligible patients. We find that disability grant threshold rules caused
recipients to have a relatively slower CD4 recovery rate of about 20-30
cells/mm3/year, or a 20% reduction in the speed of recovery around the
threshold.
