No hypotheses were stated. The research question was not categorically stated but could be inferred from the background given, and it is this: What factors influence the risk of human immunodeficiency virus (HIV) infection after percutaneous exposure to HIV-infected blood
Design of the study. This is a case-control study that was conducted of health care workers with occupational, percutaneous exposure to HIV-infected blood. The case patients were those who became seropositive after exposure to HIV, as reported by national surveillance systems in France, Italy, the United Kingdom, and the United States. The controls were health care workers in a prospective surveillance project who were exposed to HIV but did not seroconvert.
The dependent variable may be said to be human immunodeficiency virus (HIV) infection after percutaneous exposure to HIV-infected blood. The independent variables may be the factors influencing this risk
Subjects. The study population included 33 case patients (23 from the United States, 5 from France, 3 from the United Kingdom, and 2 from Italy) and 679 controls (from 190 of the U.S. health care facilities involved in the CDC Needlestick Study). ...