Table 1.

Definitions of terms

Conventional variables: Variables which are indifferent to reporting errors. Report rate is an example of a conventional variable.

Correspondence rate: For an individual, correspondence rate = (corresponding amount from matches/reference amount) × 100. It is a genuine measure of reporting accuracy that is sensitive to reporting errors. It has a lower bound of 0%, which indicates that nothing in the reference set was reported eaten. It has an upper bound of 100%, which indicates that all items and amounts in the reference set were reported correctly. Higher correspondence rates reflect better reporting accuracy.

Corresponding amount from a match: The smaller of the reported and reference amounts (or the reported amount if it is equal to the reference amount).

Inflation ratio: For an individual, inflation ratio = {[(overreported amount from matches) + (overreported amount from intrusions)]/(reference amount)} × 100. It is a measure of reporting error. It has a lower bound of 0%, which indicates that there were no intrusions and that no amounts of matches were overreported. It has no upper bound. Lower inflation ratios reflect better reporting accuracy.

Intrusion: A food item that is not eaten, but is reported eaten.

Match: A food item that is actually eaten and is reported eaten.

Omission: A food item that is actually eaten but is not reported eaten.

Order prompts: Prompts used with children during the first phase of each interview to report the previous day’s intake in forward order (beginning with yesterday morning and going forward through the day to yesterday evening) or in reverse order (beginning with yesterday evening and going backward through the day to yesterday morning).

Overreported amount from a match: The amount by which the reported amount exceeds the reference amount (or zero if the reported amount is less than or equal to the reference amount).

Overreported amount from an intrusion: All of the reported amount.

Reference amount: Corresponding amount from matches + unreported amount from matches + unreported amount from omissions.

Reference set of information: Food items actually eaten (i.e., matches and omissions) and their respective amounts.

Report rate: For an individual, report rate = (reported amount/reference amount) × 100. It is a conventional measure of reporting accuracy that is indifferent to reporting errors. It has a lower bound of 0%, which indicates nothing was reported. Although 100% is typically interpreted to indicate perfect reporting accuracy, a report rate has no upper bound because there is no limit on what an individual can report. Report rates of ~100%, >100%, and <100% have been interpreted as high reporting accuracy, overreporting, and underreporting, respectively. For an individual, report rate = correspondence rate + inflation ratio.

Reported amount: Corresponding amount from matches + overreported amount from matches + overreported amount from intrusions.

Reported set of information: Food items reported eaten (i.e., matches and intrusions) and their respective amounts.

Reporting errors: Intrusions and their overreported amounts, and overreported amounts from matches.

Reporting-error-sensitive variables: Variables which are sensitive to reporting errors, and therefore better represent reporting accuracy. Correspondence rate and inflation ratio are examples of reporting-error-sensitive variables.

Sequence: Sequence refers to a child’s first or second interview. Each child was interviewed twice, once with forward-order prompts and once with reverse-order prompts. Half of the children in each race/sex group were randomly assigned to forward-order prompts during the first interview and reverse-order prompts during the second interview; the other half of each group received the complementary assignment.

Unreported amount from a match: The amount by which the reference amount exceeds the reported amount (or zero if the reference amount is less than or equal to the reported amount).

Unreported amount from an omission: All of the reference amount.