The difference that was measured

The design is sound: multicenter, parallel-arm, randomized. It analysed 786 participants with abdominal obesity, 389 in the avocado group and 397 in the habitual diet group. Participants were 74 percent female, mean age 51±14 years, mean body mass index 32.9±5.4 kg/m2. The duration was 26 weeks. The mean difference in total LDL particle concentration is -49.1 nmol/L, with a 95 percent confidence interval of -83.6 to -14.5 and a P value of .005.[1]

Now the rest of the list. No significant difference was observed in LDL particle size. None in LDL subclasses. None in triglyceride-rich lipoprotein particles. None in HDL particles or in apolipoproteins A or B. When one value in a panel of correlated measures comes out significant, it may suggest that value is the measure most sensitive to the intervention; read together with the width of the panel, the same outcome also fits the expected spread. This trial on its own does not supply what would separate the two.[1]

The distance between a measure and an endpoint

The release sourced from Penn State's Department of Nutritional Sciences converts the difference into roughly a 4 percent lower cardiovascular risk. That number was not measured in the trial; it is an estimate derived from a lipoprotein measure. The 14 percent to 29 percent range the same release gives for comparison is associated with improving the overall diet, and so comes from a different kind of evidence. Placed side by side the two figures look like the same scale, when one is derived from a trial and the other from observational association.[1]

The funding side has two parts and both are worth stating. The Avocado Nutrition Center supported the research, while the paper's declaration of competing interest reports none. Both belong in the account: the first alone does not invalidate a result, and the second alone leaves who supported the parent trial invisible. The parent trial is named openly too: the Habitual Diet and Avocado Trial, of which this publication is an ancillary study.[1]

What would have to be shown

The statement this result can carry is this: in adults with abdominal obesity, 1 avocado a day measurably lowers total LDL particle concentration over 26 weeks. Going beyond that needs one of two things: the same difference repeated in an independent group as a prespecified primary endpoint, or a trial powered for events. The first is reachable; the second, at this effect size, demands a very large sample.[1]