[132] The two intervention groups received individual and group education on an energy-unrestricted Mediterranean diet from registered dietitians, as well as regular supplies of either extra-virgin olive oil or mixed nuts. The control group received a similar format of education on a low-fat diet. Statistically significant improvements in DBP, but not SBP, were found for both intervention groups when compared to controls at four years.[132] Furthermore, the two groups randomized to the Mediterranean diet experienced a significant 28-30% reduction in major cardiovascular events (MI, stroke, or death from cardiovascular causes).[133] The PREDIMED trial was subsequently retracted and republished in 2018 due to issues with the randomization process.[134] One site enrolled household members without randomization. Another assigned entire clinics to an intervention group rather than individual participants. A third site reported inconsistent use of randomization tables. In the republished paper, data was reanalyzed to account for correlations within families or clinics. The authors also reported a reanalysis of data after exclusion of participants known or suspected to have been improperly randomized. Reported results were similar after these corrections. As this is a Not Reviewed, Not Changed recommendation, the Work Group did not systematically review new evidence related to this recommendation as part of this guideline update. Confidence in the quality of evidence is low based on evidence put forth in the 2014 VA/DoD HTN CPG.[132] Issues with the randomization process of the PREDIMED trial were reported, but the corrected results were similar to those initially published.[134] Additional research is warranted to confirm these results, as well as to test the Mediterranean diet in RCTs of more diverse populations and against controls with more dissimilar baseline characteristics and intervention dietary patterns. Based on the available evidence, the benefits of this intervention outweigh the harms. 