The four health message intervention groups were : i ) information-only control ; ii ) one-sided message describing the advantages of HIV testing ; iii ) two-sided message acknowledging a superficial objection to testing ( i.e. , a 20 minute wait for results ) followed by a description of the advantages of testing ; and iv ) two-sided message acknowledging a serious objection ( i.e. , fear of testing positive for HIV ) followed by a description of the advantages of testing .