Complex sentence: He cited a study published in the journal JAIDS "which" followed two groups of young people in Uganda, and the group that had the intensive condom promotion actually was found to have a greater number of sex partners.
Split into simpler sentences: He cited a study published in the journal JAIDS "which" followed two groups of young people in Uganda. Members of group that had the intensive condom promotion actually was found to have a greater number of sex partners.