The Features of a Nutrient Study

The Features of a Nutrient Study, recommended by Prof. Heaney:

For a nutrient study, to be informative,

(1) basal nutrient status must be determined and used as an inclusion criterion

(2) the change in intake must be large enough to change nutrient status meaningfully

(3) change in nutrient status, not change in intake, must be the independant variable in the hypothesis

(4) change in status must be quantified

(5) co-nutrient status must be optimized

The Features of a systematic Review, recommended by Prof. Heaney

Included studies must all

(1) meet the five individual study criteria

(2) have the same basal nutrient status

(3) use the same charge in intake (dose)

(4) have the same co-nutrient status

(5) use the same form of he nutrient

(6) have the same duration of observation

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