title: Estimation of daily dietary fluoride intake: 3-d food diary v. 2-d duplicate plate.
abstract: The 3-d food diary method (3-d FD) or the 2-d duplicate plate (2-d DP) method have been used to measure dietary fluoride (F) intake by many studies. This study aimed to compare daily dietary F intake (DDFI) estimated by the 3-d FD and 2-d DP methods at group and individual levels. Dietary data for sixty-one healthy children aged 4-6 years were collected using 3-d FD and 2-d DP methods with a 1-week gap between each collection. Food diary data were analysed for F using the Weighed Intake Analysis Software Package, whereas duplicate diets were analysed by an acid diffusion method using an F ion-selective electrode. Paired t test and linear regression were used to compare dietary data at the group and individual levels, respectively. At the group level, mean DDFI was 0·025 (sd 0·016) and 0·028 (sd 0·013) mg/kg body weight (bw) per d estimated by 3-d FD and 2-d DP, respectively. No statistically significant difference (P=0·10) was observed in estimated DDFI by each method at the group level. At an individual level, the agreement in estimating F intake (mg/kg bw per d) using the 3-d FD method compared with the 2-d DP method was within ±0·011 (95 % CI 0·009, 0·013) mg/kg bw per d. At the group level, DDFI data obtained by either the 2-d DP method or the 3-d FD method can be replaced. At an individual level, the typical error and the narrow margin between optimal and excessive F intake suggested that the DDFI data obtained by one method cannot replace the dietary data estimated from the other method.
authors.affiliation: 1Health and Social Care Institute,Teesside University,TS1 3BA,UK.
authors.forename: N
authors.initials: N
authors.lastname: Omid
authors.affiliation: 2Centre for Oral Health Research,Newcastle University,NE2 4BW,UK.
authors.forename: A
authors.initials: A
authors.lastname: Maguire
authors.affiliation: 3School of Science and Engineering,Teesside University,TS1 3BA,UK.
authors.forename: W T
authors.initials: WT
authors.lastname: O'Hare
authors.affiliation: 1Health and Social Care Institute,Teesside University,TS1 3BA,UK.
authors.forename: F V
authors.initials: FV
authors.lastname: Zohoori
mesh_terms: D002648:Child; D002675:Child, Preschool; D004032:Diet; D015930:Diet Records; D005459:Fluorides / Q000008:administration & dosage* / Q000032:analysis; D006801:Humans; D011786:Quality Control
chemical_list: D005459:Fluorides
keywords: 2-d DP 2-d duplicate plate; 3-d FD 3-d food diary; DDFI daily dietary F intake; Diet; Duplicate plate collection; F fluoride; Fluoride; Food diaries; bw body weight