Use of handheld computers with global positioning systems for probability sampling and data entry in household surveys.

We introduce an innovative method that uses personal digital assistants PDAs equipped with global positioning system GPS units in household surveys to select a probability based sample and perform PDA based interviews Our approach uses PDAs with GPS to rapidly map all households in selected areas choose a random sample and navigate back to the sampled households to conduct an interview We present recent field experience in two large scale nationally representative household surveys to assess insecticide treated bed net coverage as part of malaria control efforts in Africa The successful application of this method resulted in statistically valid samples quality controlled data entry and rapid aggregation analyses and availability of preliminary results within days of completing the field work We propose this method as an alternative to the Expanded Program on Immunization cluster sample method when a fast statistically valid survey is required in an environment with little census information at the enumeration area level