This data were collected as a part of a multi-center prospective study aimed at assessing the HIV-1 infection rate among people with hemophilia. In particular, the individuals in the study were at risk from contracting HIV-1 from blood products made from donor's plasma. In this study, 544 patients were categorized into one of four groups based on their average annual dose of blood products. Specifically, patients were classified into high, medium, low, or no dose group. The goal of the study was to compare the HIV-1 infection rate between these dose groups. The time at which patients contracted HIV-1 is not known exactly, but were known to occur before, between, or after certain observation times. For more details pertaining to this data set see Goedert et al. (1989) and Kroner et al. (1994).
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