Countries like Ethiopia is already introduced new method of MUAC measurement for extension health workers. it is just Estimating the midpoint of the left upper arm. the the old procedure (about ten steps) is no more in use. operationally it is very good. However, is it globally accepted?
Current thinking is that estimating the mid-point "by eye" is all that is needed. This is what is now included in WHo material fro training community health workers and (I think) IMCI materials. The video at:
[url]http://www.brixtonhealth.com/MUAC.FullQuality.mpg[/url]
also available at:
[url]http://www.youtube.com/watch?v=3pQUtOsjjSY[/url]
reflects current thinking at the WHO.
You might notice that in the video the child has a mark at the mid-point of the upper-arm. This is there because the original video showed how to find the mid-point by measurement. This material was subsequently edited out at the request of the WHO.
This is absolutely no harm in finding the mid point by measurement.
Mark Myatt
Technical Expert
Answered:
14 years agoDear Mark,
Thanks for your usual support
Anonymous
Answered:
14 years agoThinking about these 2 methods of estimating the midpoint, whilst agreeing with what Mark has said, I just wonder if anybody has tried comparing the 2 methods of estimation among community health workers just to quantify how unreliable/inaccurate this method is compared to the 10 steps one.
Martha
Answered:
14 years agoAs far as I know there has been no testing to compare the methods. The results of testing will depend on what you want to compare (raw values or class membership). If you are just interested in class membership then the evidence is that colour-banded straps reduce error more than anything else.
Mark Myatt
Technical Expert
Answered:
14 years agoI am concerned with the quality of measurement. If these are very poor then children will be referred and then rejected when the measurement is properly retaken, or children that should be in the program will be missed. Proper training and periodic supervision/assessement are important.
The errors in measuring MUAC are greater than those with weight or height even by experienced anthropometrists. This relates mainly to differences in how tightly the bands are pulled and arm compression, but there are seveal other errors that are commonly seen in the field (having the arm bent, using the right arm, not having the mid point - yes it does make a difference [easily checked by measuing arm circ at centimeter intervals up the arm], etc.) Just because a measure appears to be very "simple" does not make it more accurate or precise.
There is rarely any estimate of the technical errors of measurement made or reported in surveys, screening programs, surveillance etc. Before any change in the standard procedure is made I would strongly advocate that it is properly tested to ascertain how the change affects the precision and accuracy of the measurement.
There is a literature on this topic - Please see the paper below and the references therein:
Ulijaszek SJ, Kerr DA. Anthropometric measurement error and the assessment of nutritional status. Br J Nutr 1999 September;82(3):165-77.
The abstract is as follows:
Anthropometry involves the external measurement of morphological traits of human beings. It has a widespread and important place in nutritional assessment, and while the literature on anthropometric measurement and its interpretation is enormous, the extent to which measurement error can influence both measurement and interpretation of nutritional status is little considered. In this article, different types of anthropometric measurement error are reviewed, ways of estimating measurement error are critically evaluated, guidelines for acceptable error presented, and ways in which measures of error can be used to improve the interpretation of anthropometric nutritional status discussed. Possible errors are of two sorts; those that are associated with: (1) repeated measures giving the same value (unreliability, imprecision, undependability); and (2) measurements departing from true values (inaccuracy, bias). Imprecision is due largely to observer error, and is the most commonly used measure of anthropometric measurement error. This can be estimated by carrying out repeated anthropometric measures on the same subjects and calculating one or more of the following: technical error of measurement (TEM); percentage TEM, coefficient of reliability (R), and intraclass correlation coefficient. The first three of these measures are mathematically interrelated. Targets for training in anthropometry are at present far from perfect, and further work is needed in developing appropriate protocols for nutritional anthropometry training. Acceptable levels of measurement error are difficult to ascertain because TEM is age dependent, and the value is also related to the anthropometric characteristics of the group of population under investigation. R > 0.95 should be sought where possible, and reference values of maximum acceptable TEM at set levels of R using published data from the combined National Health and Nutrition Examination Surveys I and II (Frisancho, 1990) are given. There is a clear hierarchy in the precision of different nutritional anthropometric measures, with weight and height being most precise. Waist and hip circumference show strong between-observer differences, and should, where possible, be carried out by one observer. Skinfolds can be associated with such large measurement error that interpretation is problematic. Ways are described in which measurement error can be used to assess the probability that differences in anthropometric measures across time within individuals are due to factors other than imprecision. Anthropometry is an important tool for nutritional assessment, and the techniques reported here should allow increased precision of measurement, and improved interpretation of anthropometric data
Michael Golden
Answered:
14 years agoMike is right to be concerned about the quality of measurement and the problem of rejected referrals. In CTC programs, rejected referrals are a real coverage killer and overcoming this was a key reason behind the adoption of MUAC as both a referral and admission criteria.
With CTC programs, I encourage the removal of the centre-based "filter" on admission. This "admission on referral" model means that any child referred to the program by a CHW, VHW, or community-based volunteer is admitted to the program even if only for a single day or to receive a limited package of goods (e.g. vitamin A and mebendazole and a consultation with a nurse). We note the source of the referral and take corrective action using outreach workers. In the past it was often GMP programs rather than community-based volunteers that were the source of most "inappropriate referrals". This has lessened with the use of MUAC since the problem was often a confusion between W/H and W/A.
A good case-finding method will pick up incident cases as soon as they become cases (you can check this by plotting a histogram of admission MUAC). This does happen in well-run CTC programs. For example, I recently saw a program in Kenya run by WVI (coverage was a little above 60% - the main problem was that SFP was not identifying response-failures) with an admission threshold of 110 mm and a median admission MUAC of 109 mm ... a child arriving with a MUAC below 100 mm was treated as a "critical incident" and lessons learned. This has implications for programs ... let's say you have a case-defining threshold of 115 mm and it is unlikely that you'll be measuring MUAC with an accuracy of better than 2 mm. A child might be referred with a MUAC of 114 mm but your centre staff might measure this as 116 mm. What to do? If you reject the referral then you risk damaging both timely case-finding and early treatment seeking (I would risk neither of these). If you admit you treat a "borderline" child who would probably be a case if you waited a few days but might not come back if you reject them. My inclination is to enrol such a child for a full course of treatment. Legalistic interpretation of case-defintions can be very harmful to program coverage.
If you are using MUAC to measure prevalence (and Mike's involvement with SMART means that he will probably have studied this more than I have) then errors are likely to be random so there should be little if any bias introduced.
In all cases (i.e. referral, admission, prevalence estimation), Mike is absolutely right ... "proper training and periodic supervision/assessment are important". You need to build this into admissions monitoring and into training and supervision in surveys.
I take issue with the often repeated "errors in measuring MUAC are greater than those with weight or height even by experienced anthropometrists" since the evidence is that when used with the level of staff you mention (CHWs) error is smaller for MUAC than for all other measures. We also have to bear in mind that height boards are quite rare outside of NGOs and IMCI does not cover the measurement of height. When using community based volunteers then MUAC measured with colour-banded straps is the best we can usually do. CTC programs typically use dozens of community-based volunteers (sometimes hundreds). Distributing height boards and scales and providing training to this number of staff is not usually a practical proposition. That said, Mike is right ... there are many sources of errors and these should be recognised and error minimised by training and supervision.
My preference is for colour-banded straps for most applications. Errors are lower with such straps than with numbered straps. They are used to ascertain class membership or diagnosis (e.g. SAM vs. not-SAM) rather than measurement. The appropriate measure of agreement is a generalised Cohen's Kappa (this has been discussed elsewhere in these forums).
Like Mike, I would have preferred that the change were tested (it may have been ... perhaps the forum administrator would like to contact WHO to check) but, truth be told, the more complicated measurement protocols were seldom used anyway. I'd been measuring MUAC using the current simple method for many years before I saw anyone use a string to ascertain the mid-point.
Mark Myatt
Technical Expert
Answered:
14 years agoI was in WHO when the MUAC teaching material for health workers Mark referred to was developed, and we looked at the evidence in favour of the formal measure of mid-upper arm, as we felt that the burden of proof lied on the side of the most complicated method. We also had to take into account that this is how it was measured in practice in most situations. We found nowhere any evidence that this formal measure of the mid-point of the upper arm did improve the precision / reproducibility of MUAC measure on children. I suspect this was introduced years ago based on measures in adults, where finding the precise mid-upper arm is important when you assess the nutritional status of a person with bulging biceps. The need to measure the left arm, which also often leads to long discussions, as well seems based on consideration in adults. There is indeed a possibility that the right arm circumference in increased in those involved in hard physical activity. We suspected that none of these considerations was really relevant in children. But it would be interesting indeed to test this formally.
Also, you may know that MUAC was introduced to detect SAM mainly for its association with the risk of dying. I know from first hand experience that in most studies which established this link the mid-upper arm was not assessed by a formal measure of the mid-point of the upper arm. I doubt though that this would have led to an improved prediction. By far, the most important factor related to assessment of the risk of dying is time since measurement. More frequent MUAC assessment is more likely to improve the quality of the estimation of risk (as assessed by ROC curves) than fine tuning the measure.
A last comment referring to errors in MUAC and WFH measure. A useful reference is:
"Velzeboer MI, Selwyn BJ, Sargent F 2nd, Pollitt E, Delgado H. The use of arm circumference in simplified screening for acute malnutrition by minimally trained health workers. J Trop Pediatr. 1983 Jun;29(3):159-66.
Abstract: This study investigated the observer reliability of arm circumference measures (AC) with respect to the conventionally used indices of weight for height and weight for age when all these measures are obtained under field conditions of door-to-door screening by minimally trained health personnel.
Data were collected in a Guatemalan village from 127 children aged 12 to 60 months. Five health promoters were selected by the community and were trained to measure height, weight and AC. A trained anthropometrist measured the children under ideal conditions and the promoters measured children in the community. Remeasurement was made on a sample of children to establish intra-observer variability.
The AC measures of promoters had the highest correlation with anthropometrist measures (0.8881) compared to weight for age (0.8756) and weight for height (0.7588). Field reliability of AC and weight for age measures varied little between promoters, but weight for height exhibited a large range of reliability.
The principal implication of this study is that, under field conditions, minimally trained workers make fewer and smaller errors in screening children 12 to 60 months of age with AC than with either weight for age and weight for height."
My comment to this study: beside the difficulty of measuring height and weight, already mentioned by Mark, it is often overlooked that WFH is a combined variable. When WFH is assessed, relative errors of both weight and height measures add up.
Having said all this, I agree with Mike and Mark that training is important when MUAC is introduced. Making sure the tape is correctly pulled is very important. And making sure that the measure is made in the middle arm, as assessed visually, is also important.
André Briend
Technical Expert
Answered:
14 years agoThere is no doubt that MUAC is the way to go - and the only tool to be used for screening for SAM in the community and also in busy overcrowded health centers and outpatient departments as well. That is not in question.
Random errors DO make a difference. They only cancel each other out where the mean value of a group is concerned - in the tails of the distribution (where SAM children are) they do not cancel out.
In terms of setting global policy I am amazed that Andre says "We found nowhere any evidence that this formal measure of the mid-point of the upper arm did improve the precision" - Does this mean that you also found NO evidence that it did cause a deterioration in precision and therefor introduced this change in an arbitrary fashion with no evidence either way. Complete lack of data is not the way to set global policy.
However, I do agree that it is likely that it makes less difference in children than in adults - Will the same staff be measuring MUAC in pregnant women and others? Will they have to remember to use different techniques for different age groups? Of course we should make everything as simple as possible - but not simpler than is possible. And if it makes no difference we should of course abandon the string to get the mid point of the upper arm. BUT to get it as simple as possible - ie introducing this change authoratitively requires data not guesses in Geneva.
Similarly - "most studies ...MUAC was not assessed by a formal measure of the mid-point of the upper arm. I doubt though that this would have led to an improved prediction. Is this just a blind guess?
Similarly - "More frequent MUAC assessment is more likely to improve the quality of the estimation of risk (as assessed by ROC curves) than fine tuning the measure" - on what basis is this statement made - is it just another blind guess?
The paper quoted by Andre gives Reliablity Coefficients for MUAC for the trained anthopometrist of 0.966 - and for the field staff as 0.9087 for intra-observer and 0.8401 for between observer. These are woefull figures - the measures to be reliable should have coeffients above 0.95 at least and for measures that can be totally relied upon over 0.99. The Standard deviation of the differences between the field staff and reference measurer varied from 4.5mm to 8,2mm. If we double that to get the range 95% of the differences they vary from plus to minus between 9 to 16.5mm.for the different field staff. The study is based on only 5 field staff! To me this study just shows the poor quality of the selection of field workers or their training or both. It does show the utility of proper training and formal assessment of the field staff;s ability. The calcualtions of these parameters are being built into the next version of SMART - so that it will be easy to make this assessment of staff during training - just need to do duplicate measures on 10 children - and if R is low then the staff should be retrained or replaced. As the data are gathered and reported we will get a much clearer picture and data upon which to base technical judgements.
.
Michael Golden
Answered:
14 years agoThanks Andre - I do think that we could use this forum to discuss the problems with IMCI - but not on this threed. And the advive on SAM in IMCI (and associated illness when SAM is present) has been very poor whereas the advice on the other childhood illnesses quite sound I think. This is a reflection of the training of most doctors and the number of people who are really able to give sound advice on SAM. You did make a difference.
Nevertheless, my point stands - we do need much more data - and in terms of MUAC much more research into things like the appropriate material to make the band from (the stiffer plastic is not good although durable), The best width of the bands (ones which are 15mm wide rather than 10mm give different values and are more consisent for example) - Look at the enormous literature on the widths of blood pressure cuffs - which have similar problems to MUAC. Also some form of elastic insert that gives a constant pressure would be great - have been thinking how to do this simply for years and not come up with a good idea - perhaps some of the readers will have good ideas - or have engineer/materials science friends who could think about these problems.
Anonymous
Answered:
14 years agoThe paper cited by André (Velzeboer et al, 1983) is interesting since it discusses the problems with using common anthropometric indices (i.e. W/H, W/A, MUAC) with "minimally trained health workers". Mike may find the reported reliability for MUAC to be "woeful" but the reported reliability estimates for W/H and H/A are worse. MUAC may be the best of a bad bunch. This is not, however, a fair test for MUAC since MUAC is (generally) used as a classification tool (i.e. is this child severely wasted or not severely wasted) rather than as a 'continuous' measure. This means that a measure of error suited to 'continuous' measures (e.g. weight and height) are not appropriate. When we did the background work to see if it would be advisable to use MUAC as a joint referral and admission criteria for CTC program in Malawi and Ethiopia in 2002, 2003, and 2005 we found that reliability was poor. The main main source of error was in recording with (e.g.) a MUAC of 104 mm being recorded as 140 mm (a few errors like this will cause SD error to be as large as Mike calculates). In subsequent work we tested the ability of community based volunteers to classify whether a child was above or below a threshold (110 mm). In this work we found very few errors. Importantly, the errors were in 'borderline' subjects and in the direction of higher sensitivity (e.g. a child with MUAC = 111 mm was classified as being below 110 mm but a child with a MUAC = 109 mm was not classified as having a MUAC > 110 mm). Investigations in 2003 and 2005 found that carers put pressure on community-based volunteers to pull the MUAC strap tighter in order to facilitate admisison in 'borderline' cases. The work we did informed the design of the banded numberless (Brixton Health / VALID) MUAC strap design (2005).
Mike states that "The calcualtions [sic] of these parameters are being built into the next version of SMART ...". This needs to be a generalised Cohen Kappa. I think that both types of error should be catered for since raw MUAC may, in the future, be used for treatment monitoring.
Mike writes "Also some form of elastic insert that gives a constant pressure would be great - have been thinking how to do this simply for years and not come up with a good idea - perhaps some of the readers will have good ideas - or have engineer/materials science friends who could think about these problems". This mechanism has been available since 2005 with the numberless (Brixton Health / VALID) MUAC strap design. This functionality is easily added using a rubber band and the marks already on the strap (the dashed line and the two bars on the tail of the strap are used for this purpose) . As far as I know, very few people have used this 'feature' other than during training.
Mark Myatt
Technical Expert
Answered:
14 years agoUNICEF has set up an innovations site through their Supply Division in Copenhagen that is trying to create a more efficient process for identifying needs and developing new products. They have a number of university partners, and improvements in the MUAC band would probably be of interest to them. Here's the website:
http://www.unicef.org/supply/index_50322.html
nancy binkin
Answered:
14 years agoFurther to my previous answer ... I have uploaded a document showing how to make an "equal pull" MUAC strap from Brixton Health / VALID International Ltd. (and other) design MUAC straps using very cheap and readily available materials (i.e. an elastic band, a staple, and a ball-point pen - you will also need a marker pen for other designs).
The "equal pull" MUAC strap is useful in early training for demonstrating a "not to loose but not too tight" pull when taking MUAC measurements. Each trainee has an "equal pull" strap for the first hour or so of practical training. After that that we remove the elastic band just as a parent removes training wheels on a child's bicycle.
You can find the document at:
[url]http://tng.brixtonhealth.com/node/141[/url]
This document may be freely downloaded, copied, and distributed.
Mark Myatt
Technical Expert
Answered:
14 years agoPlease can I remind participants to respect each other's inputs and opinions when joining discussions on en-net.
Since the purpose of the forum is to encourage discussion of complex issues or 'grey areas' to reach consensus on current 'best practice' we encourage people to share opinions based on their knowledge and experience as well as welcoming challenges from others, but please challenge gracefully!
This question has resulted in a wealth of useful information and opinion on how to conduct MUAC measurements and the challenges of measurement accuracy. Please can we maintain the spirit of open and vibrant discussion without deterring others from sharing their experiences.
Many thanks
Tamsin
Tamsin Walters
Forum Moderator
Answered:
14 years agoThere is a new article with reference to WHO (2010) Accuracy of MUAC in the Detection of Severe Wasting With the New WHO global standards in the Journal of Pediatrics published online June 29, 2010.
Does anyone know why the left arm. Was it because most are right arm dominant? I am sure I learned this at some point have forgotten and have been unable to locate a rationale online or in any articles.
Note from the moderator: the discussion has previously mentioned that the most likely reason for using the left arm was based on measurements in adults and the predominance of right-handedness. However, a clear published rationale is not easy to locate.
udaya
Answered:
14 years agoThe left arm issue has been covered in this forum. For example, see André Briend's contribution above.
I would like to add a WARNING about the thinking underlying the referenced article:
[url]http://pediatrics.aappublications.org/cgi/content/abstract/126/1/e195[/url]
This work assumes that there is a "gold-standard" for SAM and that this is W/H.
Let us put aside the MUAC vs. W/H debate for a moment and state the basic assumption more generally. It is that some measure of CRUDE ANTHROPOMETRY is the best available indicator for measuring the nutritional status of children. I think that this is a mistake.
The terms "nutritional status" and "anthropometric status" are often used interchangeably. Nutritional status refers to the internal state of an individual as it relates to the availability and utilisation of nutrients at the cellular level. This state cannot be observed directly so observable indicators are used instead. There are a range of observable indicators (biochemical, clinical, and anthropometric) of nutritional status, none of which taken alone or in combination are capable of providing a full picture of an individual's nutritional status. There is, therefore, no single "gold-standard" indicator of nutritional status.
While W/H may not be a "gold-standard" it may be a "good" standard. It may even be a better standard than MUAC. We don't have to guess about this. There is plenty of evidence available.
Nutritional status can be usefully defined at the individual, as opposed to the cellular, level as the ratio of nutrient reserves (muscle and fat) to the nutrient requirements of organs (brain, liver, heart, kidneys, lungs, &c.). It is generally recognised that muscle plays a special role as a nutrient reserve during infection and that infection is a major aetiological factor in (and often coincidental with) acute undernutrition. W/H expresses the relationship between weight and height. In children, about 4% of weight is nutrient reserves in muscle. About 96% of weight is, therefore, unrelated to important nutrient reserves. Height is almost completely unrelated to the nutrient requirements of organs. MUAC, however, is directly related to muscle mass and is, therefore, a direct measure of important nutrient reserves.
The evidence that is currently available suggests that an index known as the lean-mass ratio (LMR), the ratio of the estimated mass of the limbs to the estimated mass of the trunk, is the best ANTHROPOMETRIC indicator of nutritional status. The available evidence suggests that MUAC uncorrected for age or height is strongly associated with LMR and is a better indicator of nutritional status than all other practical indicators and that W/H is NOT associated with LMR and is the worst practical indicator of nutritional status.
An alternative to examining the association between an anthropometric indicator and nutritional status is to examine the prognostic or predictive value (i.e. of predicting death) of various indicators. When this has been done, W/H has been consistently shown to be least effective predictor of mortality and that, at high specificities, MUAC is superior to both height-for-age and weight-for-age. It should be noted that this makes the assumption that we are interested in child survival rather than treating "thinness".
W/H is known to depend on climate (lower in warmer climates), altitude (higher in mountains), dietary composition (e.g. higher when milk is consumed), and ethnicity. This means that the meaning of W/H variaes from place to place and person to person. This really rules it out as a "gold-standard". MUAC may also be similarly effected but (limited evidence) to a far lesser extent.
To summarise ... the available evidence consistently shows that W/H is worse than all other practical anthropometric indicators. Any other practical indicator (e.g. H/A, W/A, MUAC, MUAC/A, MUAC/H) performs measurably better than W/H. MUAC looks to be better than the others but also wins out on simplicity, cost, coverage, &c. You might want to look at:
[url]http://www.unu.edu/unupress/food/FNB_v27n3_suppl.pdf[/url]
for some detail and references.
In terms of indicators that are practical to collect in developmental and emergency settings, MUAC has the best claim to be a practicable "gold-standard" of nutritional status.
Looked at from this perspective we can interpret the referenced article to show that the WHO version of W/H may improve on the NCHS version but is, unfortunately, still not in very close agreement with MUAC and has all the inherent disadvantages of W/H.
Mark Myatt
Technical Expert
Answered:
14 years agoThanks Mark.
I am trying to find evidence about the Lean Mass Ratio (LMR). I tried to get hold of the full article by Brambilla et al: Lean mass of children in various nutritional states: Comparison between dual-energy X-ray absorptiometry and anthropometry, but did not manage...
Severine Frison
Answered:
14 years agoI have a copy of an article by Brambilla et al which uses LMR and DEXA ... it is a late proof with some reviewer comments in the margin. I can let you have this as a PDF if you contact me directly by e-mail:
mark@brixtonhealth.NOSPAM.THANK.YOU.com
remove the ".NOSPAM.THANK.YOU".
You might also like to contact André Briend about this.
Mark Myatt
Technical Expert
Answered:
14 years agoWas anyone able to find out why most recommend taking MUAC in the left arm? What should I convey to my trainees? Please respond to uthomas@jhpiego.net directly if you find something. I am finding it hard to find the answer among the other discussion going on. Thanks! udaya
udaya
Answered:
14 years agoAs far as I know ... there is no evidence base for recommending the use of the left arm in children (WHO do not recommend this in their IMCI material). It is probably just a superfluous transfer of the procedure used in adults.
Mark Myatt
Technical Expert
Answered:
14 years agoI think most people recommend using left arm when measuring MUAC just because it was mentioned in the first WHO document attempting to standardize nutritional status assessment. See :
http://dosei.who.int/uhtbin/cgisirsi/R0RiJukq0G/142530069/9
part 2, p 76 and 77.
And this advice was uncritically taken up by many of those writing about MUAC. Often they were not aware of the original document (published more than 40 y ago) but copied again and again other sources indirectly derived from it.
But, as you can see, absolutely no rationale is given. And I think there is none, at least in children.
André Briend
Technical Expert
Answered:
14 years agoThanks André but do you have a hard link to that document ... I get a session timed out message when I try to connect and then I get a search page.
Mark Myatt
Technical Expert
Answered:
14 years agoMark,
Do these links work better ?
http://whqlibdoc.who.int/monograph/WHO_MONO_53_%28part1%29.pdf
http://whqlibdoc.who.int/monograph/WHO_MONO_53_%28part2%29.pdf
http://whqlibdoc.who.int/monograph/WHO_MONO_53_%28part3%29.pdf
http://whqlibdoc.who.int/monograph/WHO_MONO_53_%28part4%29.pdf
André
André Briend
Technical Expert
Answered:
14 years agoYes. Thanks!
Mark Myatt
Technical Expert
Answered:
14 years agoI would like to reinforce Mark's warning about the paper quoted in one of the previous posts:
http://pediatrics.aappublications.org/cgi/content/abstract/126/1/e195
The introduction of the abstract says:
"OBJECTIVES The objectives of this study were to estimate the accuracy of using mid-upper-arm circumference (MUAC) measurements to diagnose severe wasting by comparing the new standards from the World Health Organization (WHO) with those from the US National Center for Health Statistics (NCHS) and to analyze the age independence of the MUAC cutoff values for both curves."
This suggests indeed that the authors believe that WFH is the "true" diagnostic criteria for SAM. This is somehow misleading. And there is no rationale for that. Over the last 20y, many papers showed that there is a mismatch between MUAC and WFH but it is a mistake to assume that this means that MUAC is "inaccurate". There is no real rationale for using WFH as a gold standard, apart from tradition. One might just as well write papers showing the WFH is a poor predictor of MUAC and therefore WFH is "inaccurate".
The relevance of these indicators to select patients should be tested against an objective functional outcome. This has been done repeatedly for MUAC and WFH with mortality and it was shown again and again that MUAC is more closely associated with mortality than WFH.
Other criteria such as simplicity, cost. (as discussed in the FNB paper) should also be taken into account. They are all in favour of MUAC as well.
Interestingly, this discussion about weight and height based indices and circumferences is not specific to malnutrition. The same discussion is going on regarding whether to use BMI (another weight and height based index) or rather circumference based indices in overweight patients. See references:
Kragelund C, Omland T. A farewell to body-mass index? Lancet. 2005; 366: 1589-91.
Klein S, Allison DB, Heymsfield SB, Kelley DE, Leibel RL, Nonas C, Kahn R; Association for Weight Management and Obesity Prevention; NAASO, The Obesity Society; American Society for Nutrition; American Diabetes Association. Waist circumference and cardiometabolic risk: a consensus statement from Shaping America's Health: Association for Weight Management and Obesity Prevention; NAASO, The Obesity Society; the American Society for Nutrition; and the American Diabetes Association. Am J Clin Nutr. 2007; 85: 1197-202.
These papers are interesting and suggest that taking BMI as gold standard to define obesity is not the best choice.
I have no opinion on this issue, but interestingly, those in favour of using indices based on circumferences in overweight patients give the same rationale as MUAC advocates for the last 20y + for SAM, namely a closer link with functional outcome. Indeed first examining the link with an outcome is the way to go.
So please stop worshiping WFH as a golden idol, and please don't write any more papers showing that there is a mismatch between MUAC and WFH or that MUAC is "inaccurate" to predict WFH..
André Briend
Technical Expert
Answered:
14 years agoI have been thinking and working just a little bit on the issue of dropping of the left arm rule.
I did a little exercise measuring MUAC without asking for the left arm and found that the left arm was presented in the vast majority of cases. This was because carers tended to hold the child with their left arm leaving their most dextrous (right) hand free. The child's free arm (i.e. the arm measured) is then the left arm.
With the left arm only rule we measure the favoured arm of left-handed children. I suppose that we think this OK because few people (global estimates range from 10% to 15%) are left-handed but, if there is a difference in muscle mass between the two arms with the most favoured arm having the bigger mass, we are discriminating against left handed children.
If the mother is left handed then we will get the right arm instead. There is the standard "nature vs. nurture" arguments about whether handedness is inherited or learned (it seems to be a bit of both). Either way the child of a left handed mother is more likely to be left-handed than the child of a right handed mother. I think this means that we may be more likely to measure the least favoured arm of both left and right handed children if we drop the left arm only rule.
It seems to me that we should drop the left arm only rule.
Does this make sense?
Mark Myatt
Technical Expert
Answered:
14 years agoI join my voice to Mark as i have been asking is there is any true evidence that show that right arm has a more muscle mass than left arm? i mean for the under 5 years who yes use their right arm but is the difference significance between the two arm? one other query is toward the left handed children , should we take the right MUAC.
More challenging is the children with cereberal palsy or paralysed children who are having pathologic muscle atrophy!! what should we do is the W/H index is enough and edema.
Thanks all for your copius assistance
Tarig Abdulgadir
Answered:
14 years agoI think that if we drop the left arm only rule we will end up (most of the time) measuring the least favoured arm because that is the arm that is presented to us.
In the case of disabled children ... I think that using W/H is not a solution. Kyphosis, scoliosis, inability to stand, weekness, limblessness &c. all affect the height / length measurement. Also, most PHCs in developing countries do not have height boards and IMCI does not cover height measurement of W/H look-up and calculation. Better, I think, to treat disabled children as discretionary admissions or "visible severe wasting" admissions. We have the issue of monitoring and discharge ... I suggest monitoring weight and discharging of (e.g.) 15% weight gain.
Mark Myatt
Technical Expert
Answered:
14 years agoMy experience has been the opposite. I check MUAC on 50-100 kids per day in rural southern Malawi. The mothers, most of whom are right-handed, are holding their child in their right arm since it is stronger -- they are in line getting their children screened and don't need their other hand at that time. With the child in their right arm, they then present the child's right arm to me for MUAC and i have to ask them to switch the arm that they are holding the child with. Perhaps the populations that we work with are very different but i am actually very surprised when the mother presents the child's left arm to me.
Indi Trehan
Answered:
14 years agoRegarding whether to measure the left arm routinely when measuring MUAC in young children, it is probably not important. Hand dominance does not begin to be expressed until age 2-3 years, and is not fully established until 5-6 years of age, so there is little reason to think one arm would be larger in circumference than the other in this age group. Nonetheless, the left arm only rule does remove a decision from the measurer, which is, in general, a good thing.
Bradley A. Woodruff
Technical Expert
Answered:
14 years agoIndi's report is interesting. I may have this wrong. Doing this at an OTP site with mothers feeding the child with RUTF (with their right hand) may have biased my findings. Any other experiences?
Mark Myatt
Technical Expert
Answered:
14 years agoI know it's a little away from the point, and I guess that somebody has already thought about it but, what about measuring thigh circumference? Indeed, the choice of right or left will not be a problem anymore since children use both in the same way!
It doesn't appear to be a common anthropometric criterion and it's not a WHO child growth standard but why?
Thigh and upper arm compositions aren't similar?
Hervé Le Perff
Answered:
13 years agoI know it's a little away from the point, and I guess that somebody has already thought about it but, what about measuring thigh circumference? Indeed, the choice of right or left will not be a problem anymore since children use both!
It doesn't appear that it is an anthropometric criterion and it's not a WHO child growth standard but why? Upper arm an thigh have not a similar composition?
Hervé Le Perff
Answered:
13 years agoYes. The upper arm and thigh have similar composition. A lot of work has been done with different measures including calf and thigh circumferences. I did some work (a long tome ago as a junior researcher) on calf circumference in the elderly ago. It was a promising indicator being strongly related to activities of daily living (ADL) and other quality of life (QOL) indicators.
The problems, I think, with using the thigh are (1) accessibility in older males and (2) acceptability (I'm not sure I'd like a stranger to put his hand up my wife's and daughters' dresses AND I'm not sure that I would fell comfortable or safe measuring this indicator in the field). These have meant that we have tended to avoid thigh circumference.
BTW ...legs may be favoured. In sports science they call this "bilateral deficit" and use gait analysis and training to correct this in athletes. Acrobats and gymnasts lead with different legs for different "tricks" ... box-splits (e.g.) are usually done with the stronger leg leading. The old saw that "lost people walk in circles" is true but it is not clear if this is due to favoured legs or some form of navigational confusion (blindfolded people tend to walk in circles but the direction of the turn is not consistent). The favoured leg hypothesis may be nonsense ... although I can think of an evolutionary "just so" story about lost children not wandering too far from their last known position being advantageous in the "struggle for life".
Mark Myatt
Technical Expert
Answered:
13 years agoThanks Mark.
I agree about the problems you mentioned. But in the case of SAM in 6-59 months old children, wouldn't measure of thigh circumference be as accessible and acceptable as measure of MUAC?
Is there any study carried out on thigh circumference in that specific population? Or on comparison of MUAC and thigh circumference?
Hervé Le Perff
Answered:
13 years agoWe'd have to get the trousers off the older males but we sometimes have to remove shirts for MUAC. It is known that the opportunities of unsupervised contact with children offered by working in the humanitarian sector attracts pedophiles to NGOs. I am concerned that the use of thigh circumference (TC) blurs the boundary between acceptable and unacceptable touching making child-protection difficult.
This article (e.g.) :
[url]http://tropej.oxfordjournals.org/content/27/5/267.abstract[/url]
compares reports MUAC and TC that thigh circumference has some advantages over MUAC. I think that these advantage may be outweighed by child-protection problems with TC.
Try the following Pubmed searches:
[url]http://www.ncbi.nlm.nih.gov/pubmed?term=thigh%20circumference%20malnutrition[/url]
[url]http://www.ncbi.nlm.nih.gov/pubmed?term=thigh%20circumference%20nutrition[/url]
I hope this is of some use.
Mark Myatt
Technical Expert
Answered:
13 years agoHi Mark,
Thank you very much for the link to an interesting study by Zeitlin and co-workers.
However I am taken aback by your assertion, 'It is known that the opportunities of unsupervised contact with children offered by working in the humanitarian sector attracts pedophiles to NGOs.' Could you also provide us with some evidence for this?
Thank you
Carlos Grijalva-Eternod
Answered:
13 years agoAgain, I agree, but I think that in terms of child-protection, the main issue is more the unsupervised contacts than the TC measurement itself. But I share your concern.
I thank you for this article and for your replies, it is of some use! I just wanted to have an idea on the reason of preferring MUAC to TC.
Hervé Le Perff
Answered:
13 years agoHervé ... You are right ... adherence to considered guidelines and proper supervision is essential. We are getting there with guidelines and monitoring procedures but (IMO) we still have a very long way to go.
Carlos ... I am taken aback by you being taken aback. Here some documentation ...
[url]http://www.hapinternational.org/pool/files/you-feel-like-you're-nothing.pdf[/url]
[url]http://www.hapinternational.org/pool/files/no-one-to-turn-to-embargoed-till-27-5.pdf[/url]
[url]http://www.hapinternational.org/pool/files/fmr15-8.pdf[/url]
[url]http://www.hapinternational.org/pool/files/no-one-to-turn-to-embargoed-till-27-5.pdf[/url]
[url]http://www.savethechildren.org.uk/en/docs/sexual_violence_and_exploitation.pdf[/url]
[url]http://www.hapinternational.org/pool/files/bso-handbook.pdf[/url]
Plenty more available. I though this was a widely known problem.
Mark Myatt
Technical Expert
Answered:
13 years agoHi Mark,
I was honestly shocked by your statement as I obviously did not know about this problem. Thank you for all the links, I will read them carefully.
Nonetheless, I now feel sceptical as to whether paedophiles are attracted to NGOs, as you state, for the opportunities it provides; or whether this problem emerges due to working dynamics i.e. abuse of power. Something akin to that observed in catholic priests with children, soldiers in occupied countries, police with demonstrators, etc.
But this has nothing to do with MUAC. Thank you again for this information.
Carlos Grijalva-Eternod
Answered:
13 years agoYou may be right. Sexual psychopathy, situational or otherwise, is not my field. Probably a bit if both. Either way ... we need to be careful to avoid it.
Mark Myatt
Technical Expert
Answered:
13 years agoDiscussion of the issue of sexual abuse and violence perpetrated by
humanitarian workers against women and children in beneficiary populations has been moved to the cross-cutting issues forum area:
[url]http://www.en-net.org.uk/question/392.aspx[/url]
Discussion relating to measuring MUAC should continue on this thread.
Tamsin Walters
Forum Moderator
Answered:
13 years agoI am trying to purchase MUAC tapes for use in Haiti- can anyone recommend a site where I can purchase?
Kathleen Lamaute
Answered:
13 years agoHi Kathleen
You can purchase from TALC (Teaching Aids at Low Cost) here:
[url]http://www.talcuk.org/accessories/small-coloured-insertion-tape-muac-115mm.htm[/url]
Tamsin Walters
Forum Moderator
Answered:
13 years agoCheck the local UNICEF office. MUAC straps are a standard UNICEF supply item wherever they support CMAM. UNICEF produce their own straps and distribute them from their own stocks as (I believe) an essential commodity. See:
[url]https://supply.unicef.org/unicef_b2c/mimes/catalog/images/MID_UPPER_ARM_CIRCUMFERENCE_MEASURING_TAPES.pdf[/url]
and:
[url]https://supply.unicef.org[/url]
Mark Myatt
Technical Expert
Answered:
13 years agoThanks for your suggestion. I am not able to access their online ordering without a password and I am not able to get one.
I have written and called them- but no response.
Kathleen Lamaute
Answered:
13 years agoKathleen,
If you don't hear from anyone at UNICEF Haiti in response to your post, email me at eboldon at sbhfhaiti. org and I can forward your request and contact info to them.
Ellen Boldon
Answered:
13 years agoFrom Ann Burgess:
To find TALC MUAC strips try getting into the TALC shop via [url]www.talcuk.org[/url] (you should not need a password) or email Hilary Heine at info@talcuk.org .
Tamsin Walters
Forum Moderator
Answered:
13 years ago