Development of a hand-held personal digital assistant-based food diary with food photographs for Japanese subjects

Hand-held personal digital assistant (PDA)-based food diaries have been developed for self-monitoring of dietary intake, but the accuracy of these diaries is unclear for patients with diabetes. The aim of the study was to assess the accuracy and feasibility of use of a new PDA-based food diary, including food photographs. The study included 44 Japanese participants without diabetes (mean age 23 years) and 16 Japanese patients with type 2 diabetes (mean age 53 years). The PDA-based food diary was used for 7 consecutive days. Information about all dietary intake on the 7th day of PDA self-monitoring was collected by a 24-hour recall interview on the 8th day. The PDA-based data for dietary intake on the 7th day were then compared to the 24-hour recall data for the same period. Feasibility was assessed based on the frequency and timeliness of self-monitoring. There was no significant difference in daily totals for energy, protein, carbohydrate, and fat between the two methods in each group. Pearson's correlation and intraclass correlation coefficients showed strong significant relationships for all variables between the two methods in both groups. Bland-Altman plots did not indicate any bias in estimated daily caloric intake. Participants recorded 98% of their meals in the PDA, with 75% of entries recorded within 6 hours after the meal starting time. The findings suggest that the PDA-based food diary is a potential clinical method to estimate dietary intake and may be a beneficial tool for self-monitoring of dietary intake.