A paper being released in the August issue of the American Journal of Tropical Medicine and Hygiene illustrates how technology can improve knowledge needed to help prevent malaria, one of the world’s leading fatal infectious diseases.
A team of researchers from the Centers for Disease Control and Prevention (CDC) developed a new method for survey sampling and data collection that utilizes personal digital assistants (PDA) with Global Positioning Systems (GPS). The devices enabled the scientists to collect high-quality, statistically valid and population-representative data on insecticide-treated bed net (ITN) ownership and usage from several thousand households in the West African countries of Togo and Niger.
Using the GPS and PDA systems enabled the researchers to rapidly generate a complete list of households within a selected area. They were then able to randomly choose households from that list and use the GPS to navigate back to the selected households to conduct interviews, according to author Jodi Vanden Eng, M.S., M.P.H. “What made this process so effective is that interviewers were able to create lists, — sometimes with more than 500 households — in the morning and by the afternoon they were able to interview a random sample of those households. Before we developed this method using these devices, it usually took days, or even weeks to complete the same task.”
Surveys using GPS-based data collection offer more accurate sample estimates and other clear advantages over previous techniques. One such traditional method includes spin the bottle, where a bottle is literally spun to determine the direction surveyors will start their household search. The PDA technology, using an electronic questionnaire, incorporates built-in data checks to greatly reduce human error typical of commonly used pencil-and-paper methods. Data in the PDA/GPS program can be aggregated into a single database within minutes and checked upon entry to immediately clarify any data conflict.
By using this methodology, the authors evaluated the impact of free distribution of long-lasting insecticide treated bed nets for malaria control with national childhood immunization campaigns. Results were presented to the Ministry of Health, program managers, international scientists and policymakers within hours of completing data collection.
The ability to rapidly share data from the surveys can have an impact on programs for malaria and other diseases. “Such rapid reporting can contribute to data-driven decision making and help to influence the targeting of program resources and activities,” explains co-author Adam Wolkon, MPH.
Realizing that there had to be a way to get faster and more accurate study results led the CDC researchers to develop the PDA and GPS method, however, they soon found that other advantages also came with incorporating this technique in developing countries. “Although some of our team members from West Africa had no experience with computers, with just a five-day training session, they quickly leaned how to use these devices,” says Ms. Vanden Eng. “And, we were able to power the PDAs with our car battery, making them an excellent alternative to use where bringing a laptop computer would be impossible.”
Although initially developed for use in prevalence or coverage surveys in developing countries, the researchers see this method being applied in a wide variety of public health situations such as disaster and relief efforts to identify underserved geographic areas. This approach may also be useful to relief organizations in the distribution and allocation of resources and aid. The researchers are even offering the GPS software that they developed to other scientists to help further additional studies. The CDC is also evaluating other public health uses for PDA technology such as tracking laboratory specimens collected in the field with bar code scanners, and using smartphone technology (handheld devices integrating mobile phone and PDA functionality) to transfer data in real-time from the field.