SPAs are conducted in a sample of formal sector health facilities in a country. Pharmacies and individual doctors’ offices are typically not included in a SPA. Typically, a SPA collects data from 400-700 facilities, selected from a comprehensive list of health facilities in a country (sampling frame), categorized by facility type, managing authority (public and non-public), and by region. The sample is selected to provide indicators at the national level for the different facility types and managing authority as well as aggregate indicators at the regional level. SPAs can also be done in a census of facilities, depending on the total number of facilities in the country.
Usually, hospitals are oversampled as they exist in small numbers in a country. The data are weighted during analysis to ensure that the data are proportionally representative when presented. To do this, a multiplier (weight) is applied to the data to ensure that the contribution of facilities to the total is proportionate to their existence in the country.
The sampling approach for providers and clients at each health facility has been improved in the revised SPA to maximize the number of priority clients observed, including first antenatal care (ANC) clients, new family planning (FP) clients, and sick young infants under two months.
SPAs are fielded by teams made up of interviewers, usually health workers but sometimes staff of the national statistics organization. These interviewers collect data from the facility in-charge and the most knowledgeable person(s) available for each service using five instruments in the revised SPA core questionnaire.