Rapid Surveys are small, community-based surveys that typically take 5-7 days to gather field data and 2-3 weeks to analyze and prepare a final presentation and report. Such studies are often referred to as "quick and clean" prevalence surveys because they are done in a short time, adhere to proper statistical methodology, and are cross-sectional in nature.
A reference site is maintained by Professor Ralph Frerichs to support rapid surveys. The site contains rapid survey software and publications on surveys and survey methodology. Please be aware, however, that many published cluster surveys would correctly not be termed "rapid surveys" because of their size and duration (but are included nevertheless in the Rapid Survey reference site) and some published cluster surveys do not use the correct variance formula, as described in the Rapid Survey Course.