Table 1.

Definitions of terms in alphabetical order (Baxter, Guinn et al.; Baxter et al., 2007a, 2007b; Smith et al., 2007)

Correspondence rate for energy: This is the percentage of total observed energy that was reported correctly. It was calculated for each child as: [(total corresponding energy from matches)/(total observed energy)] × 100. It is a genuine measure of reporting accuracy that is sensitive to reporting errors. It has a lower bound of 0% (indicating that no observed items were reported eaten). It has an upper bound of 100% (indicating that all observed items and amounts were reported correctly). Larger values indicate better reporting accuracy. Correspondence rate equals report rate minus inflation ratio.

Corresponding energy from matches: For each match, this is the smaller of reported and observed energy (or reported energy if it is equal to observed energy).

Inflation ratio for energy: This is a non-negative augmentation to correctly reported energy that is based on incorrect reporting. It was calculated for each child as: {[(total overreported energy from matches) + (total overreported energy from intrusions)]/(total observed energy)} × 100. It is a measure of reporting error. It has a lower bound of 0% (indicating that there were no intrusions and that no amounts of matches were overreported). It has no upper bound (because there is no limit on what a person can report). Smaller values indicate better reporting accuracy. Inflation ratio equals report rate minus correspondence rate.

Intrusion: This is a food item that was not observed eaten but was reported eaten in some nonzero amount for that meal.

Match: This is a food item that was observed eaten in some non-zero amount and was reported eaten in some non-zero amount for that meal.

Omission: This is a food item that was observed eaten in some non-zero amount but was not reported eaten for that meal.

Overreported energy from intrusions: For each intrusion, this is the entire amount of reported energy.

Overreported energy from matches: For each match, this is the amount of energy by which reported energy exceeds observed energy (or zero if reported energy is less than or equal to observed energy).

Report rate for energy: This is the reported percentage of observed energy. It was calculated for each child as: [(total reported energy)/(total observed energy)] × 100. It is a conventional measure of reporting accuracy which disregards reporting errors. It has a lower bound of 0% (indicating nothing was reported). It has no upper bound (because there is no limit on what a person can report). Traditional interpretation is that values close to 100% indicate high reporting accuracy, values greater than 100% indicate overreporting, and values less than 100% indicate underreporting. Report rate equals correspondence rate plus inflation ratio.

Total observed energy: For each child, this was the sum of (total corresponding energy from matches) + (total unreported energy from matches) + (total unreported energy from omissions).

Total reported energy: For each child, this was the sum of (total corresponding energy from matches) + (total overreported energy from matches) + (total overreported energy from intrusions).

Unreported energy from matches: For each match, this is the amount of energy by which observed energy exceeds reported energy (or zero if observed energy is less than or equal to reported energy).

Unreported energy from omissions: For each omission, this is the entire amount of observed energy.