title: Development of a new instrument for evaluating individuals' dietary intakes.
abstract: OBJECTIVE
  With the aim of developing a new dietary instrument for assessing an individual's usual intakes, we evaluated a hand-held personal digital assistant with camera and mobile telephone card, called Wellnavi (Matsushita Electric Works, Ltd, Osaka, Japan).
  
  
  METHODS
  Twenty-eight college students majoring in food and nutrition in Okayama University of Japan voluntarily participated in this study.
  
  
  METHODS
  Applying a cross-sectional study design, participants were asked to keep 1-day weighed food records. Digital images of all recorded foods were obtained simultaneously and sent to registered dietitians by a mobile telephone card. The following day, a 24-hour recall was obtained. These procedures were repeated after 6 months. Participants' opinions about the three methods were determined using a questionnaire.
  
  
  METHODS
  Differences in estimated median nutrient intake among the three methods were compared by Wilcoxon matched-pairs signed rank test. Relationships among the nutrient estimates by each method were evaluated using Spearman rank correlation coefficients.
  
  
  RESULTS
  We found no significant differences between the Wellnavi method when compared with food records for most nutrients, except zinc, manganese, vitamin E, saturated fatty acid, polyunsaturated fatty acid, and dietary fiber. The median correlation coefficients for the nutrient estimates were 0.66 between the Wellnavi method and the food records. The survey showed that 57.1% of subjects considered the Wellnavi method the least burdensome of the three methods and the least time consuming (16 minutes) to record daily diet. About half of participants indicated that they would be willing to use the Wellnavi for 1 month to record their diet.
  
  
  CONCLUSIONS
  This study suggests that a hand-held digital assistant may be a valid and convenient instrument for evaluating dietary intake.
authors.affiliation: Department of Public Health, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan. dahong@md.okayama-u.ac.jp <dahong@md.okayama-u.ac.jp>
authors.forename: Da-Hong
authors.initials: DH
authors.lastname: Wang
authors.forename: Michiko
authors.initials: M
authors.lastname: Kogashiwa
authors.forename: Shohei
authors.initials: S
authors.lastname: Kira
mesh_terms: D000328:Adult; D040421:Cell Phone; D034201:Computers, Handheld; D003430:Cross-Sectional Studies; D015930:Diet Records; D004046:Dietetics / Q000295:instrumentation* / Q000379:methods; D002149:Energy Intake / Q000502:physiology*; D005260:Female; D006801:Humans; D011939:Mental Recall; D015596:Nutrition Assessment; D010781:Photography; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D018709:Statistics, Nonparametric; D011795:Surveys and Questionnaires