Definition of "tertile" []

• Any of the two points that divide an ordered distribution into three parts, each containing a third of the population. (noun)
• Any one of the three groups so divided. (noun)

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• "About 55% of those whose brains were in the upper tertile (third) of atrophy developed Alzheimer's, while none of those whose brains in the bottom tertile (little or no atrophy) developed Alzheimer's."
• "Risk for developing metabolic syndrome was highest in the tertile with the greatest weight fluctuations, independent of whether these subjects gained weight overall or not."
• "For the Beer brand, the overall TV ROI was $0.23 and among the high HSP index tertile of programs it was $1.61."