“Everyone can take photos.” Feasibility and relative validity of phone photography-based assessment of children’s diets – a mixed methods study

Abstract

Background: Dietary assessment methods that are user-friendly, simple, yet valid are of interest to both researchers and participants, particularly for use in disadvantaged settings, where language barriers and low levels of education are often present. We tested if parents taking photos of what children ate, using mobile phones, would be a feasible, acceptable method that could still provide information with adequate relative validity. Methods: We used a mixed-methods design, with parents of 21 5-to 7-year-olds from disadvantaged areas in Sweden. Parents reported all dietary intake, during non-school hours, on three days (two weekdays) using a photo method (PM). The PM consisted of simple instructions and a fiduciary card, but no training, equipment or software. Text messages could be sent if necessary. As a reference method, parents completed three 24-h recalls (24HRs) with an interviewer each following day. The next week, parents completed a 9-item semi-FFQ regarding the preceding week. The outcomes were intakes (in dl) of 9 food groups, categorised as fruits and vegetables, energy-dense sweet/salty foods, and sweet drinks. Agreement with the reference 24HRs was assessed using correlations, median differences and Bland-Altman plots. Parents completed an open-ended questionnaire on barriers and facilitators. Data collectors provided complementary information. Qualitative data was analysed using qualitative manifest analysis. Results: Nineteen parents (90%) provided complete data. The majority (n = 13) spoke Swedish as a second language, few (n = 4) were proficient. Compared to 24HRs, intakes measured by PM correlated well for all categories (Spearman's rho = 0.609-0.845). However, intakes were underreported, significantly so for fruits and vegetables; Bland-Altman plots indicated that the underestimation was fairly constant across intake levels. When the FFQ was compared to the 24HRs, parameters of agreement were generally inferior than for the PM. Parents found the PM a positive experience, primarily facilitated by its simplicity and familiarity. Barriers, mainly related to time and logistics, can inform further methodological refinements.

Validation of a life-logging wearable camera method and the 24-h diet recall method for assessing maternal and child dietary diversity

“…There are no validation studies of IAR methods for estimating DDS with which to compare these results. However, similar results have been seen in image-assisted quantitative diet recall validation studies (29,33,35,37,54) . Such error usually serves to attenuate the association between DDS and health or other outcomes and diminish power to detect it (18) .…”

“…In high-income country contexts, validation research has also been conducted, in controlled settings, into the use of prospective photos taken by the study subject (often using a mobile phone) during food preparation and/or eating episodes (34)(35)(36)(37) . In these studies, information documented in the photos regarding foods consumed, portion sizes and wastage is later used by researchers to compute nutrient intake.…”

Performance of the Digital Dietary Assessment Tool MyFoodRepo

“…Portion size estimation relying on the capture of a single image was proven to reduce user burden as automated estimations are not affected by the user's lack of knowledge about quantities [36,37]. Photography can also decrease data collection time and participant's disturbances in complex settings such as school cafeterias [11], and facilitate study implementation in environments with lower health and nutrition literacy or language barriers [38,39]. MFR would nonetheless benefit from more precise estimations of portion sizes.…”

Brief parental self-efficacy scales for promoting healthy eating and physical activity in children: a validation study

“…Children’s dietary intake was measured using a mobile phone photography-based method developed for use in the HSSP trial [ 48 ]. Parents took photos of all food and drink consumed and left-over for 3 days, including one weekend day, and sent them to the researchers via multimedia messaging service (MMS).…”

“…The volume of selected foods, including fruits, vegetables, sweets, and soft drinks, present in the photos was coded by a nutritionist trained in the method. In a relative validation study [ 48 ], in yet another group of parents with a variation in educational and immigrant backgrounds ( n = 19), the photo method was compared to 24-h recalls (conducted by licenced dietitians) on 3 days during a week. The photo method showed acceptable validity relative to the reference method of 24-h recalls, with correlations between the volumes of these four food groups as assessed by the photo method and by the reference method ranging from 0.562 to 0.688.…”