The MVA calculator is for health facility supply managers and distributors who calculate the number of manual vacuum aspirators (MVA) to keep in stock in health facilities. Using facility data, the Ipas MVA calculator will estimate appropriate quantities of Ipas MVA Plus® and Single-Valve aspirators to meet expected caseload. It uses a statistically based forecasting methodology developed by John Snow, Inc., based on average daily caseload and reuse factor for Ipas MVA instruments of 25.