Study designs of evaluations included in the review
Randomised controlled trials (RCTs) that lasted at least 24 weeks were eligible for inclusion in the review.
Specific interventions included in the review
Studies that evaluated one of the following comparisons: two NRTIs plus one non-NRTI versus two NRTIs plus one PI; two NRTIs plus one non-NRTI versus two NRTIs; or two NRTIs plus one PI versus two NRTIs. The included studies administered combinations of lamivudine, abacavir, efavirenz, amprenavir, zidovudine, didanosine, stavudine, nelfinavir, zalcitabine, nevirapine, indinavir, delavirdine, atazanavir and saquinavir; the PI was given with or without ritonavir.
Participants included in the review
Studies of human immunodeficiency virus-infected antiretroviral-naive patients (with no previous antiretroviral treatment), or patients with limited antiretroviral exposure (up to 14 days exposure to non-NRTIs or PIs, less than 6 months' exposure to zidovudine, diadanosine, zalcitabine or stavudine, or previous exposure to NRTIs in less than 80% of patients), who were at least 16 years old were eligible for inclusion. The majority of the included studies were conducted in antiretroviral-naive patients. Where reported, the patients had a mean age of 33 to 43 years, 7 to 35% were female, and 5 to 76% were non-white.
Outcomes assessed in the review
The studies had to report one or more of the following outcome rates (based on intention-to-treat data): death, new acquired immunodeficiency syndrome (AIDS)-defining events, virological suppression and withdrawals because of adverse events. Clinical progression was defined as the proportion of patients with a new Center for Disease Control and Prevention stage C event; virological success was defined as the proportion of patients with a viral load of less than 50 copies/mL. The mean or median CD4 count increase (cells/mm2) was also reported.
How were decisions on the relevance of primary studies made?
The authors did not state how the papers were selected for the review, or how many reviewers performed the selection.