think this was meant for me.
It seems that you may be increasing the MUAC threshold in order to maintain program numbers. This does not seem very sensible to me. MUAC < 125 mm is a common cutpoint for MAM. Using this threshold, or a higher threshold, will increase sensitivity but decrease specificity. This means that you will admit a large number of false positive cases (i.e. cases that would not go on to die in the absence of treatment). A MUAC of 134 mm is quite large for younger children. Using the example of one year old girls ... the WGS reference has median MUAC - 142 mm with SD of about 11 mm. This means that in a healthy population of one year female children living in conditions ideal for growth we would expect to find about 23% of girls aged one year with MUAC < 134 mm (compared with c. 1% using MUAC < 115 mm). Many of these children will not need treatment.
I take the view that we run child survival programs and this needs us to identify children who would die without treatment but would survive with treatment. Work done by ENN's concurrent wasting and stunting group (WaSt TIG) shows that a case-definition using extreme low MUAC and/or extreme low WAZ detects all, or nearly, all such cases including all those with WHZ < -3. See this article.
ENN's WaSt TIG are currently doing the additional work suggested in this article and have found similar results using cohort data from Bangladesh, DRC, Ghana, Guinea-Bissau, India, Indonesia, Nepal, Niger, Peru, Philippines, Senegal, and Sudan.
I think the best approach would be to use a case-defintion such as:
MUAC < 115 mm OR WAZ < -3
might do better than increase the MUAC cutpoint and better than using:
MUAC < 115 mm OR WHZ < -3
for admission into therapeutic feeding programs. By extension, the case-definition:
MUAC < 125 mm OR WAZ < -2
might be well suited to deciding admission into supplementary feeding programs.
using WAZ has the advantage of detecting children with concurrent wasting and stunting who we know to be at high risk of near term mortality. WAZ is well suited to clinic / hospital bases screening provided good infection control is used.
I hope this is of some use.