One of the most important aspects of any surveillance system is degree of completeness. We
conducted a multiple source capture-recapture study using the 1994 Massachusetts Uniform
Hospital Discharge Data Set (UHDDS) and Medicaid claims data to evaluate the
completeness of the state's AIDS registry. We used encrypted social security numbers as the
primary link to ensure confidentiality. For cases that did not link in the first round owing to
missing social security numbers, we linked using gender and date of birth. Staff reviewed …