Portion Sizes from 24-Hour Dietary Recalls Differed by Sex among Those Who Selected the Same Portion Size Category on a Food Frequency Questionnaire

Background

Accounting for sex differences in food portions may improve dietary measurement; however, this factor has not been well examined.

Comparison between Self-Completed and Interviewer-Administered 24-Hour Dietary Recalls in Cancer Survivors: Sampling Bias and Differential Reporting

Self-completed 24 h dietary recalls (24-HRs) are increasingly used for research and national dietary surveillance. It is unclear how difficulties with self-completion affect response rates and sample characteristics. This study identified factors associated with being unable to self-complete an online 24-HR but willing to do so with an interviewer. Baseline 24-HRs from the ASCOT Trial were analysed (n = 1224). Adults who had been diagnosed with cancer in the past seven years and completed treatment, were invited to self-complete 24-HRs online using myfood24^®. Non-completers were offered an interviewer-administered 24-HR. One third of participants willing to provide dietary data, were unable to self-complete a 24-HR. This was associated with being older, non-white and not educated to degree level. Compared to interviewer-administered 24-HRs, self-completed 24-HRs included 25% fewer items and reported lower intakes of energy, fat, saturated fat and sugar. This study highlights how collection of dietary data via online self-completed 24-HRs, without the provision of an alternative method, contributes to sampling bias. As dietary surveys are used for service and policy planning it is essential to widen inclusion. Optimisation of 24-HR tools might increase usability but interviewer-administered 24-HRs may be the only suitable option for some individuals.     

Predicting Perceived Problems in Self-Administered 24-Hour Dietary Recalls: A Quantitative Think-Aloud Study Comparing Automated Self-Assisted 24-Hour Dietary Assessment Tool (ASA24®) and INTAKE24© in University Students

Demographic and psychosocial factors concerning dietary assessment error have been explored, but few studies have investigated the perceived problems experienced when completing dietary recalls. The aim of this research was to (i) compare the perceived problems encountered in two commonly used self-administered 24-hour dietary recall (24HR) programs (INTAKE24© and ASA24^®) and (ii) explore whether mindful and habitual eating are associated with perceived problems during dietary recall. A randomised quantitative crossover design and think-aloud methodology were employed. Undergraduate university students (N = 55, M_age = 25.5, SD = 8.2, 75% female) completed a food habits and mindfulness questions pre-program, one 24HR (whilst thinking aloud), and a systems usability scale post-program. A week later, they completed the other 24HR (whilst thinking aloud). During a pilot, a coding frame of perceived problems was devised to quantify participants’ perceived problems. INTAKE24© generated significantly fewer perceived problems across all categories compared to ASA24^® (17.2 vs. 33.1, p < 0.001). Of the participants, 68% reported a preference for INTAKE24© over ASA24^®. Hierarchical multiple regression showed that habits and systems usability were significant predictors of perceived problems for INTAKE24© only. No significant predictors were found for ASA24^®. The results provide insight into perceived problems people may encounter when using 24HR tools.     

Ratios of Food Amounts across Three Portion Size Categories on a Food Frequency Questionnaire in Men and Women

BackgroundFor some quantitative food frequency questionnaire (QFFQ) items, data may be insufficient to set gram weights for multiple portion size (PS) categories. Ratios of food amounts across PS categories may be used to quantify these PS for less frequently consumed food items.ObjectiveTo explore the ratios of food amounts reported in 24-hour dietary recalls (24HDRs) by a sample of participants in a cohort study who chose the A (smallest) or C (largest) PS category on the QFFQ, relative to the food amounts for those who chose the B PS category.DesignThis study was conducted as a cross-sectional design.Participants/settingData were from participants (n=2,360) who completed three 24HDRs and the QFFQ in a calibration study of the Multiethnic Cohort Study in 1994-1997.Main outcome measuresMedian food amounts were calculated from 24HDRs for participants who selected each PS category (A, smallest; B; and C, largest) of items on the QFFQ. A-to-B and C-to-B ratios were computed if reported by five or more people in the 24HDRs: A-to-B ratios for 68 items (men) and 88 items (women); C-to-B ratios for 93 items (men) and 79 items (women).Statistical analyses performedThe t test was used to compare the mean A-to-B ratios and C-to-B ratios as preset on the QFFQ with those from the 24HDRs and to examine sex differences. Analysis of variance was used to compare the mean ratios among race and ethnicity groups.ResultsMean A-to-B and C-to-B ratios were 0.71±0.15 and 1.45±0.35 in men and 0.71±0.15 and 1.44±0.40 in women based on the 24HDRs. Compared with the original QFFQ PS (A-to-B ratio=0.5±0.07; C-to-B ratio=1.8±0.30), the ratios were closer to 1 both in men and women (P<0.001). There were no significant sex differences or racial or ethnic differences.ConclusionsThese results provide guidance on appropriate ratios to use to set values for small and large PS categories on a QFFQ, particularly for items with insufficient information on usual PS.