Can coverage methods be used to give an estimate of MAM coverage? What are the realistic assessment implications (time, staffing, resources) of piggy-backing MAM coverage to a survey for coverage of SAM?
SQUEAC is a method designed to assess selective therapeutic feeding services i.e. services with defined criteria of selection or eligibility in order to benefit from the service. For outpatient and inpatient therapeutic care, generally, this eligibility is quite clear cut and applicable across the board.
Often there is high variance in the forms of SFP being implemented (blanket, targeted, alternating blanket and target, protection rations etc.). Determining who should be eligible for it is not clear cut, which makes sampling very complicated. In general there is very little value in assessing SFP coverage unless the service uses very clear eligibility criteria. Should SFP coverage assessment be found to be critical and valuable, then adding SFP coverage onto SQUEAC is quite straightforward, but will potentially require some additional resources in terms of either time or staffing to complete.
If management of MAM is by set criteria e.g. SFP for children aged 6 - 59 months who have MUAC < 125 and ≥ 115, then if we are to assess coverage of both SFP and outpatient therapeutic care in one survey, the implications will be as follows:
- In SQUEAC surveys, you will have to create two priors - one for outpatient therapeutic coverage and one for SFP coverage. This would mean that you will either use more time to do both investigations to come up with two priors, or that you will use more people so that you can do parallel investigations within the same period of time
- If you aim to assess SFP and outpatient therapeutic care through a nested sample, then this would mean that the second stage sampling method will have to be a census-type of sampling approach (i.e. house- to-house) rather than a snowball sampling approach (i.e. active and adaptive case finding). This is because unlike SAM, MAM cannot be as easily distinguished by mere sight or description so only MAM cases bordering on severe tend to be found adaptively using key words or key informants. This means that the snowball method may not be exhaustive for MAM cases compared to SAM cases. If this is done, this will most likely bias the results upwardly. The implications of a census-type approach in terms of either time or staffing can be minimal. To be able to cover the same number of villages with house-to-house will take more time as compared to active and adaptive case finding. However, because MAM is more prevalent than SAM, you will require a lower number of villages to sample to obtain your target sample size. Therefore, you may only need to do MAM case-finding in a small number of villages as compared to more villages with SAM case-finding. Hence, there need not be a great increase in cost. In settings where villages are quite small (i.e. village size of 50 or less households or up to 300 population) house-to-house will be just as quick if not quicker than active and adaptive case finding.
In summary, the technical difference lies in the use of a census approach rather than active and adaptive case-finding, which may impact on the time and/or resources required for a wide-area survey.
Source: Guevarra E, Norris A, Guerrero S and Myatt M,
Assessment of Coverage of Community-based Management of Acute Malnutrition, CMAM Forum Technical Brief July 2012, Version 2: September 2014. Accessible online
here.