Relative risk (RR) and 95% confidence interval (CI) for treatment and virological failure in comparative studies: RR and 95% CI for studies comparing TDF/3TC/NVP, TDF/FTC/NVP, TDF/3TC/EFV, and TDF/FTC/EFV to another regimen are depicted. Regimens containing non-US Food and Drug Administration-approved antiretrovirals (ARVs) or ARV combinations are not shown. RR for prospective studies are depicted as black points, and RR for retrospective studies are depicted as gray points. Points to the left of midline represent improved virological efficacy for the tenofovir (TDF)-containing regimen. Points to the right of midline represent improved virological efficacy for the comparator regimen. Abbreviations: AZT, zidovudine; 3TC, lamivudine; ABC, abacavir; ATV/r, boosted atazanavir; ddI, didanosine; EFV, efavirenz; FTC, emtricitabine; LPV/r, boosted lopinavir; NVP, nevirapine; NVP XR, extended-release nevirapine; RAL, raltegravir; RPV, rilpivirine; TDF, tenofovir.