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A changing landscape: web-based methods for dietary assessment in adolescents

Storey, Kate E.

Current Opinion in Clinical Nutrition and Metabolic Care: September 2015 - Volume 18 - Issue 5 - p 437–445
doi: 10.1097/MCO.0000000000000198
ASSESSMENT OF NUTRITIONAL STATUS AND ANALYTICAL METHODS: Edited by Kristina Norman and Dwight E. Matthews
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Purpose of review Adolescents’ dietary intake is an important determinant of health and well-being and is influenced by a complex interaction of environmental, social, psychological, and physiological factors. The complexity of the adolescent diet makes its assessment prone to error, which has prompted researchers and clinicians to turn to technology to reduce this error. Previous reviews have been conducted regarding the use of technology in dietary assessment for adults; however, there are no known reviews for adolescents. Therefore, the purpose of this review is to describe the practical considerations for web-based dietary assessment methods and to evaluate recent evidence on their validity and implications.

Recent findings There are numerous web-based dietary assessment methods that are available, valid, and reliable for use in the adolescent population. Web-based methods include both native and web-based applications (or ‘apps’), and have been developed for use as food records, 24-h dietary recalls, and food frequency questionnaires.

Summary Web-based methods provide an efficient, cost-effective and practical solution to assess dietary intake; they are less burdensome to respondents and reduce errors and bias. Furthermore, adolescents are technologically savvy and often prefer the use of technology. Web-based methods should be considered when assessing adolescents’ dietary intake.

School of Public Health, University of Alberta, Edmonton, Alberta, Canada

Correspondence to Kate E. Storey, PhD, RD, School of Public Health, University of Alberta 3-50 University Terrace 8303 – 112 Street, Edmonton, Alberta T6G 2T4, Canada. Tel: +1 780 492 9609; fax: +1 780 492 5521; e-mail: kate.storey@ualberta.ca

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INTRODUCTION

It is well established that adolescents’ dietary intake is an important determinant of health and wellbeing for current and future health outcomes. Not only is adolescence a time of rapid growth and development, resulting in increased nutritional requirements, but is also a time of increased independence and autonomy. Nutrition-related behaviors formed during adolescence often track into adulthood and therefore have become a focus for early intervention. Notably, the association between poor diets during adolescence and the development of chronic diseases has made the assessment of adolescent dietary intake an increasing priority. Therefore, accurate assessment of adolescent dietary intake is essential to determine overall nutritional status, changes in dietary intake over time and because of nutritional intervention, as well as the impact of diet on health-related outcomes such as chronic diseases.

There are numerous dietary assessment methods. Two methods, the dietary food record and the 24-h dietary recall (24-hdr), are intended to measure what is actually consumed over a predetermined amount of time. The food-frequency questionnaire (FFQ) measures an individual's perception of his or her own intake over an estimated period of time. However, all self-reported methods rely on the ability of the individual to accurately recall items consumed. Even when using food records, individuals frequently postpone recording items and therefore may not be able to accurately recall their intake [1]. Traditionally, these methods require either an individual or interviewer to collect the information using a paper-based format and are often considered burdensome for both persons. In all cases, the individual and/or the interviewer must be properly trained in areas such as portion sizes, cooking/preparation methods, and the detail required to accurately assess an individual's diet. Like adults, many adolescents experience recall bias, response bias, and underreporting of total energy intake [2▪]. Although adolescents have increased cognitive ability to record or remember their intakes compared with younger children [3▪], they are also more independent and have increased consumption of foods away from home. Additionally, adolescents may have limited knowledge of food and food preparation [4▪]. As such, the dietary intake of adolescents is influenced by a complex interaction of environmental, social, psychological, and physiological factors. This complexity of the adolescent diet makes its assessment in this population prone to error. In an effort to reduce this error and to improve our ability to accurately assess dietary intake, researchers and clinicians alike have been turning to technology.

Technology, specifically native and web-based applications, allows individuals to record food intake with the assistance of portion size estimates in the form of food photographs, and also allows for real-time data entry. Not only can this reduce error in the recording of foods consumed, but it can also reduce interviewer bias. Since the start of the Digital Revolution, technology is ever evolving. Mobile (smartphone and tablet) usage has surpassed fixed Internet access [5▪], and over 50% of the world's population owns a mobile phone [6▪]. As such, the Internet is being accessed on the go. It is expected that in the near future, the smartphone will become the primary way to connect to the Internet. Therefore, for the purposes of this review, web-based dietary assessment methods will include both native and web-based applications (or ‘apps’), and will include only those developed/validated for use with adolescents in a clinical or research setting. Although previous reviews have been conducted regarding the use of technology in dietary assessment for adults [7,8], there are no known reviews for adolescents. Therefore, given the challenges in measuring the dietary intake of adolescents and the advent of new web-based methods of assessment, the purpose of this review is to describe the practical considerations for web-based dietary assessment methods and to evaluate recent evidence on their validity and implications.

Box 1

Box 1

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PRACTICAL CONSIDERATIONS FOR WEB-BASED DIETARY ASSESSMENT METHODS

Web-based methods of dietary assessment provide a unique and cost-effective means to gather dietary intake data from large numbers of respondents simultaneously over wide geographic areas. As well, web-based methods are less burdensome and may reduce error and bias. Notably, web-based methods have low administration and data entry costs as they utilize electronically linked databases, which eliminates the need for manual data entry and therefore makes data entry errors nonexistent. Given that traditional dietary intake assessment methods may be subject to social desirability, in which respondents feel the need to provide others with a favorable impression of oneself, web-based dietary assessment tools may also provide improved accuracy because of their anonymity and privacy. It has been shown that anonymity and privacy are important determinants for honest reporting among adolescents [9▪]. Web-based dietary assessment methods can also be tailored to specific populations, such as adolescents, by using enhanced pictures or interactive components to further reduce error. Although there is some concern in the literature regarding the ability of respondents to navigate web-based dietary assessment tools, Internet use is near-ubiquitous among adolescents [10▪], and there is now a ‘mobile culture’ among youth. It is thus no surprise that adolescents have been shown to prefer assessment methods that utilize technology [9▪].

Although web-based methods have many advantages, there are also limitations. Researchers and/or clinicians are often not able to control the setting when data collection takes place; therefore, the environment, motivation, and time of day may affect data collection. Web-based methods utilize self-report, which is independently associated with limitations such as accuracy and literacy. Further, many individuals may not have access to a computer or mobile device and Internet connectivity may be an issue. Although web-based methods have several limitations, the advantages have led many health professionals, organizations, and researchers to move toward their use. Although there are challenges when using self-reported data, the adaptability and flexibility of web-based tools makes the Internet an efficient, cost-effective and practical solution when collecting and managing data, especially for adolescents.

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WEB-BASED DIETARY ASSESSMENT TOOLS

Each method of dietary assessment (i.e., food records, 24-hdr, FFQ) has relative strengths and limitations, and techniques. Respondent burden, training, measurement error and population-specific barriers are all important considerations that must be evaluated before selecting a method of dietary assessment. Although it is beyond the scope of this review to discuss these strengths, limitations and techniques of each method in detail, the following section will provide a brief overview of each method in the context of web-based tools. Known web-based dietary assessment tools are organized by assessment method (i.e., food records, 24-hdr, FFQ) and discussed in terms of application and validation and are summarized in Table 1[11▪,12,13▪▪,14,15,16▪,17,18▪–26▪,27,28▪,29,30▪,31▪].

Table 1

Table 1

Table 1

Table 1

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Food records

Food records are generally considered the gold standard in dietary assessment [1]. Respondents keep detailed dietary records for a period of one or more days, and therefore must be trained and motivated to successfully complete the record. Although food records do not rely on memory, they do require literacy. In school-aged adolescents, this is generally not a concern; however, it is an issue that must be considered when determining the utility of this method. Although the food record is considered the gold standard, errors and bias often occur, especially for adolescents. Of note, previous studies have indicated that adolescents were reluctant to record their food intake using the paper and pen method around their peers, and altered their intake to simplify reporting [11▪]. Food records have a high respondent burden, which often result in underreporting of total energy intake.

Web-based food records significantly reduce respondent burden. This is important, as lack of motivation by the respondent is a considerable error associated with food records. Because of the high subject burden during transcription of foods, individuals may choose to reduce intake to decrease the amount of effort required to complete a food record [1]. For web-based food records, participants may still need to be trained regarding record keeping, portion sizes, food preparation methods, and consuming meals away from home; however, prompts and visual aids can be added to the web-based method. Although other web-based dietary assessment methods can be conducted using a personal computer, food records require a mobile platform. Previous research has shown that, when compared with adults, adolescents are more confident and competent at using mobile applications and actually prefer this form of technology [32]. Although there are a number of mobile applications in the market (for purchase or free to download) to document food intake, only few have been validated specifically for use with adolescents in a clinical or research setting. Two known applications, The Food Record app [11▪] (FRapp) and the mobile telephone food record (mpFR) [12,13▪▪,14], include both images and text to record food intake and notably require fiducial markers as a size reference within captured images and will be described in detail. Tools, such as Viocare's Food Intake Visual and Voice Recognizer [33] and the Diet Data Recorder System, have been developed and tested, but not specifically with adolescents [34].

The FRapp has been used with adolescents aged 11–14 years in a free-living environment and includes six dietary input methods that can be enabled within the app. These include: ‘capturing and annotating meal images, typing in free text food descriptors, speech-to-text conversions with food item extraction, record voice for later playback, capturing food label/nutrition facts/barcode photos, and selecting from recently consumed food sets.’ (p4) [11▪]. Of note, the FRapp does recommend that when at home, adolescents weigh and measure their food. In comparison, the mpFR, which was developed as part of the Technology Assisted Dietary Assessment (TADA) program for use with 11–18 year olds, requires that the respondent take a picture of the food before and after eating and then the images are sent to a server. The images are analyzed and the food item(s) are identified along with the volume of food consumed. The results are then sent back to the respondent who is asked to verify and/or modify the information [13▪▪]. Both of these tools have been found to be amenable for use with adolescents and provide similar, or improved reporting accuracy in comparison with traditional pen and paper methods [11▪]. Adolescents found these tools easy to use, but researchers indicated that additional training would improve user cooperation [11▪,12].

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24-Hour dietary recall

A 24-hdr is a recall of all foods and beverages consumed in the previous day and is one of the most widely used methods to assess dietary intake. Traditionally, a trained interviewer conducts a 24-hdr; however, web-based methods have been established to collect dietary intake data. Although there is less subject burden compared with other methods, the accuracy of the 24-hdr is dependent on the memory of the respondent. Further, multiple days of intake are required to adjust for intra-individual variation to produce estimates of usual intake. Because a trained interviewer does not facilitate web-based 24-hdr, cues to promote cognitive processes must be included. Portion size images and reminders of beverage intake are generally provided in addition to probing for ‘add-ons’, which, for example, reminds the respondent to select the spread that was added to toast. As well, many tools have a summary screen, in which the respondent can view all foods/beverages reportedly consumed and provides another opportunity to add/delete items from the recall to improve accuracy. Although there is no limit to the amount of foods, combinations of foods, cooking methods, and other detailed information that can be provided to the interviewer during a traditional interviewer-administered 24-hdr, there are limits when using a web-based tool. However, most web-based tools now incorporate thousands of food items and therefore should not be seen as a significant limitation.

There are a number of web-based 24-hdr that have been validated for use with adolescents including the Waterloo Eating Behavior Questionnaire (WEB-Q, grades 6–8) [15,16▪], which was validated most recently using the Web-Survey of Physical Activity and Nutrition (Web-SPAN, 11–15 year olds) [17], INTAKE 24 (11–24 year olds) [18▪], which was developed based upon the Self-Completed Recall and Analysis of Nutrition (SCRAN24, 11–16 years) [35▪], the Synchronized Nutrition and Activity Program (SNAP, 7–15 year olds) [19▪], the Web-Based Dietary Assessment Software for Children (Web-DASC, 8–11 year olds) [20▪], the Children and Adolescents’ Nutrition Assessment and Advice on the Web (CANAA-W, grades 5 and 6, mean age 11 years), which was based on the Young Adolescents’ Nutrition Assessment on Computer (YANA-C, 11–14 year olds) [21▪], the National Cancer Institute's Automated Self-administered 24-h Recall for Kids (ASA24-Kids-2014, ≥10 year olds) [22▪], and the Food Intake Recording Software System version 4 (FIRSSt4, 10–13 year olds) [23▪]. FIRSSt4 was developed based on ASA24 and is now available as ASA24-Kido [4▪]. Additional tools such as Dietitians of Canada's eaTracker(≥14 years) [24▪] and the US Department of Agriculture's (USDA) SuperTracker [25▪] have also been used with adolescents. Although many of the above tools still require a personal computer, some have moved to native-based apps and therefore could be used in place of food records.

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Food frequency questionnaire

Owing to the expense and methodological issues surrounding usual intake when utilizing food records and 24-hdr, FFQs are often used. A FFQ is often used in research to collect data on long-term dietary intake data that generally would not be feasible using the two previous methods, and thus are very practical in epidemiologic applications. The typical FFQ contains a list of foods with options for choosing the appropriate frequency of consumption of each food. Food lists vary from only a few foods to over a hundred foods. Generally, FFQs do not allow for open-ended responses; however, an exception would be questionnaires that contain information on portion sizes. Although FFQs are an attractive method to assess usual intake, special considerations must be taken for adolescents. The cognitive ability of respondents must be taken into consideration before selecting a FFQ as the primary dietary assessment method. FFQs have been shown to be more reliable with increased age of respondents [1]. Web-based FFQs have been shown to reduce errors associated with skipped questions or multiple responses [9▪].

There are a variety of web-based FFQs that have been developed for use with adolescents. Most, like those developed by NutritionQuest (Block Kids, 10–17 year olds) [26▪,27], the Norwegian Mother and Child Cohort Study (MoBa) FFQ (13–14 year olds) [28▪], the Belgian Web-based FFQ (12–18 year olds) [29], and the Adolescents and Surveillance System for the Obesity prevention (ASSO) Project FFQ (14–17 year olds) [30▪,31▪] are simply web-based FFQs that can be used interchangeably with a traditional paper-based FFQ. Others, such as the Diet History Questionnaire II (DHQ II) and the Canadian Diet History Questionnaire (C-DHQ II) [36▪] from the National Cancer Institute, allow for more complex skip algorithms to reduce respondent burden, but has not been validated for use with adolescents.

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CONCLUSION

Web-based methods provide an efficient, cost-effective, and practical solution to assess dietary intake. Furthermore, adolescents are technologically savvy and often prefer the use of technology. Web-based methods are less burdensome to respondents and reduce errors and bias associated with data entry and social desirability, and may also provide improved accuracy due to their anonymity and privacy. Although the choice of web-based dietary assessment method depends largely on the suitability of the approach (i.e., food record, 24-hdr, FFQ) and logistical considerations, there are numerous web-based methods that are available, valid, and reliable for use in the adolescent population. Web-based methods should be considered when assessing adolescents’ dietary intake.

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Acknowledgements

None.

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Financial support and sponsorship

None.

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Conflicts of interest

There are no conflicts of interest.

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REFERENCES AND RECOMMENDED READING

Papers of particular interest, published within the annual period of review, have been highlighted as:

  • ▪ of special interest
  • ▪▪ of outstanding interest
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REFERENCES

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Keywords:

24-h dietary recall; adolescents; dietary assessment; food frequency questionnaire; food records; web-based methods

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