TABLE 2.

Nutrition-specific items in Nutrition QUality Evaluation Strengthening Tools (NUQUEST)

Study design	Nutrition-specific items
Randomized controlled trial	The frequency and quantity of the intervention exposure under study are accurately and reliably measured. The relevant baseline exposure is measured and taken into account. The baseline exposures of all groups have been maintained over the course of the study. Adherence to the intervention and control intakes is monitored in a reliable and accurate manner. The interval between the intervention and outcome is of sufficient duration to observe an effect, if there is one.
Cohort study	The frequency and quantity of the exposure under study are accurately and reliably measured. The relevant exposure at baseline is measured and taken into account. The baseline exposure differences between the groups have been maintained over the course of the study. The interval between the exposure and outcome is of sufficient duration to observe an effect, if there is one.
Case-control study1	The exposure under study is accurately and reliably measured. The baseline exposure differences between the groups have been maintained over the course of the study. The interval between the exposure and outcome is of sufficient duration to observe an effect, if there is one.

¹All items except for the exposure assessment in NUQUEST for case-control studies are found in the nutrition-specific section of NUQUEST. An exception was made for NUQUEST for case-control studies because the generic assessment items for this study design included an exposure ascertainment item. Nutrition-specific guidance was developed for this generic item to highlight the specific issues in assessing nutrition exposures, and to highlight the fact that retrospective case-control study designs are particularly vulnerable to recall bias.