Centric Systematic Area Sampling or CSAS was developed in 2002 and was initially used to test and reform the community-based therapeutic care or CTC model of service delivery, later referred to as community-based management of acute malnutrition (CMAM) or integrated management of acute malnutrition (IMAM).

Since then it has been used as an evaluation tool but has proved too resource-intensive to be used for routine monitoring. Although largely superseded in this area by the less resource intense SQUEAC and SLEAC, CSAS is still an effective method for estimating and mapping coverage with useful precision and can be used by teams experienced with the technique and for final evaluations.

CSAS Design

CSAS uses a two-stage sampling design. The first stage is a systematic spatial sample of the entire service area to select the communities to survey. The sample is therefore representative of the whole area. The second stage is an active and adaptive case-finding method that finds all or nearly all SAM cases in the communities being surveyed. Hence, the sample is representative of the communities surveyed.

CSAS Outputs

CSAS yields the following results:

  • Overall coverage estimate
  • Local coverage estimates which can be represented as a coverage map
  • Ranked list of barriers

CSAS Coverage Map
CSAS Coverage Map


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Myatt, M., Feleke, T., Sadler, K. & Collins, S., 2005. A field trial of a survey method for estimating the coverage of selective feeding programmes. Bulletin of the World Health Organization, 83(1), pp.20–26. DOI   PubMed

Myatt, M. and Valid International. 2004. New Method for Estimating Programme Coverage. Field Exchange, 21, p.3. Link

Myatt, M.M., Khara, T.T. & Collins, S.S., 2006. A review of methods to detect cases of severely malnourished children in the community for their admission into community-based therapeutic care programs. Food and nutrition bulletin, 27(3 Suppl), pp.S7–23. DOI   PubMed

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