Development and Evaluation of a Web-based Computer-Assisted Personal Interview System (CAPIS) for Open-ended Dietary Assessments among Koreans

The accuracy of dietary assessments has emerged as a major concern in nutritional epidemiology and new dietary assessment tools using computer technology to increase accuracy have been developed in many countries. The purpose of this study was to develop a web-based computer-assisted personal interview system (CAPIS) for conducting dietary assessment and to evaluate its practical utilization among Koreans. The client software was developed using Microsoft's ClickOnce technology, which allows communication with a database system via an http server to add or retrieve data. The system consists of a tracking system for the subject and researcher, a data-input system during the interview, a calculation system for estimating food and nutrient intake, a data-output system for presenting the results, and an evaluation system for assessing the adequacy of nutrient and food intake. Databases of the nutrient composition of common food (n = 3,642), recipes for common dishes (n = 1,886), and photos of serving sizes for food and dishes (n = 4,152) were constructed, and logical processes for data collection, calculation, and output were developed. The functionality, on-site applicability, and efficiency of CAPIS were evaluated in a convenience sample of 181 participants (61 males, 120 females; aged 24 to 85) by comparing with manual 24 hour recall method with paper questionnaire. The CAPIS was functioned adequately in the field survey in terms of completeness of function, security, and compliance of researcher and subjects. Regarding on-site applicability, 23.2%, 32.6%, 35.4%, and 43.7% of subjects reported that CAPIS was easier to recall their diet, to estimate the amount consumed, to communicate with the interviewer, and to concentrate on the interview than the manual method with paper questionnaire, respectively. Although CAPIS required more interview time (9 min 42 sec) compared to the manual method (7 min 30 sec), it saved time and cost for data coding and entry (15 min 35 sec) and gave high satisfaction from the prompt feedback after interview to the subjects, which increase efficiency to apply on the field survey. Our results suggest that the newly developed CAPIS is suitable for conducting personal interviews for dietary assessment in Korean population.