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When will SMART / ENA support MUAC?

This question was posted the Assessment and Surveillance forum area and has 12 replies. You can also reply via email – be sure to leave the subject unchanged.

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Mark Myatt

Frequent user

15 Mar 2010, 11:18

Just a quick question ...

We now use MUAC for admission into TFP. Some use it for admission into SFP. A recent meeting in Geneva proposed that SFP admission criteria be based on MUAC. I took a look at the SMART and ENA stuff last week. The support for MUAC is still very lacking. We have discussed this before on this forum and nothing seems to have happened. Perhaps there is something going on behind the scenes. Perhaps someone from SMART can illuminate us. How can we go about formally requesting this, much needed, addition to SMART and ENA?

Regine Kopplow

Health&Nutrition EU Aid Volunteer Concern Worldwid

Normal user

16 Mar 2010, 04:13

Very good question! I was at the regional SMART training in Bangladesh Oct 09 and there MUAC was not even considered one of the key anthropometric indicators only weight, height, age and oedema. It was said by the "experts" that MUAC is not reliable enough as an indicator. Unless MUAC is included into the nutrition software packages data analysis using excel/spss will have to continue.


Frequent user

16 Mar 2010, 17:29

Dear Regine,

In their 2009 Joint statement on identification of SAM, WHO and UNICEF mentioned that MUAC should be included in prevalence survey. See the following section:

. when MUAC is used as admission criterion, the proportion of children with a low weightfor-height does not correspond well with the proportion of children with low MUAC.
Consequently there is often a mismatch between the case loads predicted by nutrition
surveys and those actually observed. To improve planning, it is therefore vital that
the same criteria are used for estimating caseload as are being used for admission
into programmes. This means that in settings where MUAC will be used as the admission
criterion for therapeutic feeding, especially at the community level, it is important to include MUAC assessment in the nutritional prevalence surveys.

Available at:

It is regrettable indeed MUAC is not included in SMART and that "experts" neglect the potential of this simple tool to detect SAM children at the community level.

Mark Myatt

Frequent user

16 Mar 2010, 17:58

This matter has been discussed on this forum before with posters saying it was a good idea and SMART "experts" characterising it as a bad idea. We are now admitting on MUAC in TFP and SFP and the bulk of the key UNOs in this field stated (in 2009) that MUAC should be collected in surveys. I think it is time that MUAC was included in SMART and given the same attention in terms of reporting &c. as W/H.

SMART appear to be deaf to such requests. Is there any way that we can use this forum or the ENN to bring this issue to SMART's attention?

Perhaps a "straw poll" might be useful ... so who is in favour of putting MUAC into SMART?

Asmaa Ibnouzahir

SMART Survey Specialist

Normal user

16 Mar 2010, 18:03


Actually, on the upcoming version of ENA, that the experts are developing now, and that should be ready very soon, MUAC will be analyzed by the software.

When we talked about the MUAC during the regional training in Bangladesh, the key message was not that MUAC is not reliable and should not be used; What we tried to explain is that MUAC was not considered to be as reliable as WFH for estimating the prevalence of acute malnutrition in surveys. Obviously, MUAC is being widely used for screening and admission purposes. I know there are enough debates on this forum about the MUAC and the WFH, that I won't get into the debate again :-)

I think that using MUAC for the same population during surveys for example also allows you to learn more about the relationship between it and the WFH in that specific population; so that you better know how much you can rely on it during screenings. Experts might correct me if I'm wrong...

Thank you,

Mark Myatt

Frequent user

16 Mar 2010, 19:12

Good news!

Anonymous 368

MEAL Specialist

Normal user

17 Mar 2010, 06:32

I totally disagree using MUAC alone to refer a child into SFP with out considering the WFH, the survey team consider both WFH with MUAC. MUAC is sometimes measured and dirrectly assesses the amount of soft tissue on the arm and is another measure for thinness (or fatness), like WFH. It is not standardized for age, and the cutoff points are not universally accepted. Neverthless, MUAC is the best index to use in a community (for screening to identify indivdiaul children in need of referral to further assessment. Becouse MUAC is used in this manner, it is useful to appreciate the relationship between WFH and MUAC in a particular community to establish a full nutrition programme, including screeining. This is why MUAC is sometimes included in the data collected in a survey. MUAC data are often not reported or emphasized in a report, and decisions are not usually based on these data only. WFH is calculated for indivdiuals and groups using the ENA software. For detail refrence, please refer the 2008 SMART Manual.

Mark Myatt

Frequent user

17 Mar 2010, 12:46

That is almost a direct quote from page 23 of the April 2006 SMART Methodology document (this appears to be the current version according to the SMART website). I am not sure that the SMART manual deserves to be treated as holy writ. It is, perhaps, a little insulting to instruct us to "refer [to] the 2008 SMART Manual" when it is clear that many (most?) of us have referred to SMART documents, attended SMART training, applied the SMART methodology, used the SMART software &c. We have done all that and find that we need something more than is provided at present.

Briefly addressing the criticisms of MUAC :

Age adjustment : This has been tried (along with height adjustment) and has been shown to reduce the predictive power for near-term mortality of the indicator (see below for a brief discussion of why this is important). MUAC without adjustment actually works better than MUAC with adjustment.

Universality and cut-points : The exact weight cut-point for (e.g.) WHZ = -2 for a 85 cm tall boy will vary depending on the reference / standard used. There are many references / standards that could be used. Most familiar to us are NCHS-1977 and WGS. There are many more. The USA, for example, uses their own reference as do most European countries. W/H depends somewhat on body-shape and body-shape is not universal. For example, W/H using either NCHS-1977 or WGS will select fewer children from high altitude settings (large chests and short limbs) than from Sahel pastoralists (long legs and short bodies) even if the true nutritional status of both populations are identical. So, WHZ = -2 does not mean the same thing in different populations. The situation with W/H is that cut-points are not universally agreed and, even when the cut-points are the same (i.e. we all decide to use the same reference) they mean different things depending on where you use them. If this is what you mean by "universally accepted" then I fail to see the virtue of it. I think that we need to consider the purpose of our interventions. Are they child survival programs? Are they special-kind-of- thinness treating programs? I am of the opinion that they are child survival programs. In this case we need an indicator that selects children at risk of near-term mortality who can be treated with (e.g.) the CTC protocol so that their mortality risk is greatly reduced. When we look at indicators and case-defintions in this way we find that MUAC (uncorrected by age or height) outperforms all other practical indicators and W/H performs worse than all other practical indicators. This is a universal finding. It does not matter who you are or where in the world you are ... your MUAC predicts mortality consistently. This is not true of W/H. The predictive power of W/H differs from place to place and, even when it is pretty good, it is still not as good as MUAC. Now to cut-points ... there is, I believe, universal agreement that MUAC < 110 mm is the minimum SAM case-definition and (less clear-cut) that 110 mm <= MUAC < 120 mm is the minimum MAM definition. If prevalence is low or resources available we can raise these so that (e.g) SAM is MUAC < 115 mm. We are not justified, however in lowering them. It is a sort of universal agreement.

Use as a screening tool :Advise now is not to use two-stage screening (MUAC then W/H) in CTC and CMAM programs since this has been shown to create problems of rejected referrals and community disengagement and has been shown many times in many contexts to have a devastating effect on program coverage.

The relative merits of MUAC and WFH in case-definitions of acute malnutrition has been the subject of long and acrimonious debate. The SMART view is not the only view nor is it the view best supported by the available scientific evidence. Academic reviews of this topic favour MUAC above W/H. It is difficult to debate this issue since the idea that W/H is a useful indicator for GAM, MAM, or SAM is (following Jeremy Freese) "perhaps more vampirical than empirical - unable to be killed by mere evidence - the hypothesis seem so logically compelling that it becomes easy to presume that it must be true, and to presume that the natural science literature on the hypothesis is an unproblematic avalanche of supporting findings". The scientific literature favouring W/H over MUAC is sparse and consists, to a large part, of assertion untainted by evidence.

MUAC is used as an admission criteria (i.e. not just a screening / referral criteria) for SAM in CTC and CMAM programs. This is useful because many primary health centres in developing countries do not have height boards or the staff needed to make an accurate and reliable height measurement (most manuals, including SMART - Figure 5 and Pages 70-71, state that two staff are required. Some, such as guides from FANTA and MSF state that three staff are required), the IMCI syllabus does not cover height measurement or W/H calculations, and height boards are not part of essential clinic equipment packs. It may seem a strange point to have to make but it is, surely, not rational to promote an indicator of acute malnutrition such as W/H that cannot be used in most settings where acute malnutrition is a problem.

The CTC model of intervention integrates inpatient therapeutic feeding, outpatient therapeutic feeding, and targeted supplementary feeding. Some CTC programs now use MUAC as the sole admission criteria in all of these program components. The need is for surveys that can be used to estimate need so programs can plan properly. When you have programs that admit on MUAC then you need to include MUAC in surveys. I think that your definition of "decisions" is too limited. It may be that prevalence by W/H informs decisions such as whether to intervene in an area but many other decisions about the size and scope of programming can only be made using MUAC. Also, national programs such as the Ethiopian EOS are MUAC-only programs and need MUAC in surveys for all program decisions.

I think that the SMART / ENA software should strive to produce the tools needed to inform programming and avoid trying to present a consensus (i.e. W/H is entirely wholesome and MUAC is only useful for limited applications) when no such consensus exists. Many (most?) of us are using MUAC and would like SMART to help us with this rather than imply that we are weak-minded.

Anonymous 368

MEAL Specialist

Normal user

17 Mar 2010, 14:18

Dear Mark,

Sorry for mis-undertood my previous comments. First of all I appreciate the questions and all the debate reflected in the forum. Yes, I coat from I do not ahve any intention to either instruct or insult someone on profesiinal debating forum, which is unethical as a profesional researcher or development practitioner. I understood that this forum is a knoweldge sharing forum,( if mistaken you can correct me) and my intention is to reflect that many INGOs applying the SMART manual in emregency nutriton interventions. Just what I indicated in my last statement was that "for detail one can refer the SMART manual". It is not instructing you or any one. Just mentioning as a refrence which is commonly used staement in most development litrature.



Mark Myatt

Frequent user

17 Mar 2010, 16:00

Elias ... No offence was taken on my part. I hope that I have not offended you. You should be aware that the SMART is (occasionally) problematic in the way it treats indicators and in some of the procedures employed on the data. Its treatment of MUAC is, for example, outmoded. This is what prompted the original question.

Anonymous 81

Public Health Nutritionist

Normal user

18 Mar 2010, 02:44

I will leave the technical debate regarding to WHZ vis-à-vis MUAC for researchers. However, I want to say the progress made after MUAC is recognized as an independent criterion for admission. As MUAC is operationally feasible, I expect that the number of SAM cases accessing CTC/CMAM/IMAM services is increasing (I don't have figures) which is good to achieve one of the MDG indicators. Using WHZ/WFHM could be possible for INGOs who cover very limited geographic area (districts/county/townships) with enough staff. However, it is impossible to scale up at national level (decentralized at primary health care settings) by government where there is shortage/limited MOH staff and availability of measuring boards.
Some countries like Ethiopia (more than 80 million population) have already decentralized the CMAM particularly OTP services at the health posts level. The reason why it is successfully decentralized is because of using MUAC as the only admission criteria (plus oedema + .). As a result, thousands of Ethiopian severely malnourished children are now getting access to the service.
So, we have to compromise between population coverage, operational feasibility and technical debate. So it is better to go ahead using clear cut admission criteria (Oedema, MUAC, appetite/medical cxn) and straightforward discharge criteria (20% weight gain in two visits and for those admitted by oedema if the oedema disappear plus MUAC>11/11.5). Of course this is not the end of the day. Based on ongoing researches findings, things could be updated accordingly.

Mara Nyawo

Nutrition Specialist / UNICEF

Normal user

18 Mar 2010, 11:29

The inclusion of analysis of MUAC data in the SMART ENA software will be a very welcome development. We carry out many nutrition surveys and routinely collect MUAC data and improved analysis of this data (including detection of outliers and looking at data quality) would be very useful. In some communities in which we work we have seen a large mis-match in estimation of prevelance of malnutrition between weight for height and MUAC, so a standardised and more thorough analysis of MUAC data would greatly help in predicting caseload.

Will population-level cut points for MUAC be establised (as they are for WFH / HFA etc) - would these be useful, or would they have to be more population specific?

Mark Myatt

Frequent user

18 Mar 2010, 13:05

The cut points used should (for planning) be those used in program admission criteria. As for "population level" ... I think 115 mm and 125 mm for SAM and MAM will do the job. These will probably be the same as your program admission criteria.

MUAC cut-points are based on mortality risk and the relationship between MUAC and mortality is remarkably consistent across the planet. The same cannot be said for W/H. You might find the following review articles useful: and

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