[Development of the EULAT eCollect application for electronic data collection within the European-Latin American consortium towards eradication of preventable gallbladder cancer - EULAT Eradicate GBC].

The European-Latin American Consortium towards Eradication of Preventable Gallbladder Cancer (GBC) - EULAT Eradicate CVB is collecting high-quality data and samples in four Latin American countries with a high incidence of GBC: Argentina, Bolivia, Chile and Peru. The goal is to build a unique biorepository integrated with a customized informatics platform, identify, validate, and functionally characterize novel GBC risk biomarkers, and develop GBC prediction models integrating epidemiological and genetic-molecular risk factors. We decided to develop the electronic data collection application EULAT eCollect to facilitate the retrieval of socio-demographic, clinical, lifestyle, nutritional, and sample information from the 15,000 Latin Americans we are enrolling. The EULAT eCollect app reduces the time spent by study participants, limits the use of paper and ink, minimizes the costs and errors associated with completing written forms and their subsequent digitization, and allows close monitoring of local recruitment rates and data quality. We describe in this article the design and implementation of EULAT eCollect, which started with the specification of functional and non-functional requirements and ended with the implementation and subsequent validation of the four application modules: I Socio-demographic interview, II Sample information, III Case report form, and IV Food frequency questionnaire. We present both general and technical results and our experience with the Open Data Kit software, which may be of interest for future research projects, especially those on personalized cancer prevention conducted in low- and middle-income regions.