Simplified Lot Quality Assurance Sampling Evaluation of Access and Coverage or SLEAC is a rapid low-resource survey method that classifies coverage at the service delivery unit (SDU) level. The SDU may be a health centre catchment area, commune, or district. A SLEAC survey identifies the category of coverage (e.g. “low”, “moderate” or “high”) achieved by the service delivery unit being assessed. The advantage of this approach is that relatively small sample sizes (e.g. \(n ≤ 40\)) are required in order to make an accurate and reliable classification.
SLEAC can also estimate coverage over several service delivery units and is suited to wide-area use. Coverage is still classified for the individual service delivery units, then, data from individual service delivery units are combined and overall coverage for the wide area is estimated. SLEAC was originally developed as a companion method for SQUEAC but has recently been used for mapping of coverage classes in service delivery units over very wide-areas (e.g. national level).
SLEAC uses a first stage systematic spatial sample similar to that used in CSAS. Only small sample sizes (\(n ≤ 40\)) are required for each service delivery unit in which coverage is being classified. The second stage sample is an active and adaptive case-finding method as with the other coverage survey methods.
SLEAC yields the following results:
- Indicator classifications
- Can be used over wide areas to provide local indicators classifications with a map and a wide area estimate
- Ranked list of barriers
Myatt, M., Guevarra, E., Fieschi, L., Norris, A., Guerrero, S., Schofield, L., Jones, D., Emru, E. & Sadler, K. 2012. Semi-Quantitative Evaluation of Access and Coverage (SQUEAC)/ Simplified Lot Quality Assurance Sampling Evaluation of Access and Coverage (SLEAC) Technical Reference, Washington, DC: FHI 360/FANTA.
Guevarra, E., Guerrero, S. & Myatt, M., 2014. Using SLEAC as a wide-area survey method. Field Exchange, (42), p.40.
Guevarra, E., 2011. Report on Simplified Lot Quality Assurance Sampling Evaluation of Access and Coverage (SLEAC) and Semi-Quantitative Evaluation of Access and Coverage (SQUEAC) of the Sierra Leone National Community-based Management of Acute Malnutrition (CMAM). Valid International, Oxford.