Protocol - Mid-Upper Arm Circumference
- Ethnicity and Race
- Total Pregnancy Weight Gain - Abstracted From Prenatal Charts
- Total Pregnancy Weight Gain - Self-Reported Weight Gain
- Total Pregnancy Weight Gain - Weight Measured During Gestation
- Waist Circumference - Framingham Heart Study
- Waist Circumference - Waist Circumference NCFS
Description
Arm circumference is measured at the midpoint of the distance from the acromion process of the shoulder to the tip of the olecranon process of the elbow.
Specific Instructions
Several overarching, critical issues for high-quality data collection of anthropometric measures that optimize the data in gene-environment etiologic research include (1) the need for training (and retraining) of study staff in anthropometric data collection; (2) duplicate collection of measurements, especially under field conditions; (3) use of more than one person for proper collection of measurements where required; (4) accurate recording of the protocols and the measurement units of data collection; and (5) use of required and properly calibrated equipment.
The notion of recommending replicate measurements comes from the reduction in random errors of measurement and accompanying improved measurement reliability when the mean of multiple measurements is used rather than the a single measurement. This improvement in measurement reliability, however, depends on the reliability of a single measurement in the hands of the data collectors in a particular study (Himes, 1989). For example, if a measure such as recumbent length in a given study has a measurement reliability of 0.95 (expressed as an intraclass correlation coefficient), taking a second measurement and using the mean of the two measurements in analyses will improve the reliability to only 0.97, yielding only a 2% reduction in error variance for the additional effort. If, in the same study, the reliability of a single triceps skinfold measurement was 0.85, using the mean, including a replicate measurement, would raise the reliability to 0.92 and yield a 7% reduction in error variance, more than a three-fold improvement compared with recumbent length.
Because the benefits of taking replicate measurements are so closely linked with the existing measurement reliability, it is recommended that as a part of the training of those who will be collecting anthropometry data, a reliability study be conducted that will yield measurement reliability estimates for the data collectors, protocols, settings, and participants involved in that particular study (Himes, 1989). If the measurement reliability for a single measurement is greater than or equal to 0.95, the recommendation is that replicate measurement are not necessary and will yield little practical benefit. If the measurement reliability is less than 0.95, the recommendation is to include replicate measurements as prescribed.
If replicate measurements are indicated because of relatively low reliability, a second measurement should be taken, including repositioning the participant. A third measurement should be taken if the first two measurements differ by more than 1.0 cm. If it is necessary to take a third measurement, the two closest measurements are averaged. Should the third measurement fall equally between the first two measurements, all three should be averaged.
First, the upper arm length is measured using bone landmarks, and the midpoint distance is marked for the circumference measurement. Measure the right arm at the level of the upper arm midpoint mark.
The following protocol is part of a national examination study.
Note: Detailed videos illustrating this procedure can be found here: https://www.youtube.com/watch?v=p9lwWPLvYpY
Availability
Protocol
Mid-Upper Arm Circumference
Upper Arm Length
In this study, the length of the upper arm is measured to obtain reliable arm circumference (Section 3.4.7). Exam staff will measure the upper arm length on participants aged 2 months and older.
1. Position the SP. Direct the SP to turn away from you. Ask him or her to stand upright with the weight evenly distributed on both feet; the right arm bent 90º at the elbow, and the right palm facing up. Demonstrate the correct position if necessary (Exhibit 1).
Exhibit 1. SP position for upper arm length and midpoint
2. Mark the Measurement Site. Locate the end of the spine of the right scapula by following the scapula out to the arm until it makes a sharp V-turn to the front of the body (Exhibit 2). Using the cosmetic pencil, make a horizontal line on the uppermost edge of the posterior border of the spine extending from the acromion process (see Exhibit 3).
Exhibit 2. Upper arm bony landmarks
Exhibit 3. Marking spine extending from acromion process
3. Take the Measurement. Hold the zero end of the measuring tape at this mark and extend the tape down the center of the posterior surface of the arm to the tip of the olecranon process, the bony part of the mid-elbow (Exhibit 4). Exhibit 5 shows the measurement on an infant. Note: Some SPs with large arms have a lot of sagging fat and flesh near the elbow. If the arm length is obtained by bringing the tape down the back of the arm and around this extra flesh to the tip of the olecranon process, then call “BE” to the recorder who will record the measurement and add the “Bowing Effect” comment beside the Upper Arm Length measurement in ISIS.
Exhibit 4. Marking upper arm length midpoint
Exhibit 5. Infant upper arm length
Important: The tape must be centered on the posterior surface of the arm. Exhibit 6 shows the correct placement of the measuring tape centered on the posterior surface of the arm, whereas Exhibit 7 shows the measuring tape placed incorrectly.
Exhibit 6. CORRECT tape placement for upper arm length | Exhibit 7. INCORRECT tape placement for upper arm length |
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4. Record the Result. Call the result to the recorder, who will enter this number on the ISIS screen. Keep the measuring tape in position.
Mark the Midpoint. After the recorder enters the result, the application will divide the value in half to calculate the midpoint of the measured length. A computer-generated voice will repeat the measurement aloud and call out the midpoint. While the examiner holds the tape in place, the recorder will make a horizontal mark at the midpoint and cross this mark with a perpendicular line centered on the posterior surface of the arm (see Exhibit 3-13). This mark defines the site at which the arm circumference will be measured. Thus the examiner may need to remove the tape to allow the recorder to complete the appropriate cross mark. Finally, tell the SP to relax the right arm. Proceed to the arm circumference measure.
Arm Circumference
The anthropometry protocol calls for three circumference measures: arm circumference on participants 2 months and older, abdominal or waist circumference on participants 2 years and older, and hip or buttocks circumference on participants 12 years and older. The arm circumference is measured on the right arm at the level of the upper arm mid-point mark. The examiner makes this mark on the posterior surface of the arm immediately after measuring the upper arm length. The procedures for making the mid-arm circumference mark are explained in above, Upper Arm Length, shown earlier. This section describes the procedures for measuring the arm circumference:
1. Position the SP. Ask the SP to turn so that you stand facing his or her right side. Have the participant stand upright with the weight evenly distributed on both feet, the shoulders relaxed, and the right arm hanging loosely at the sides. Flexing or tightening the arm muscles will yield an inaccurate measurement.
2. Take the Measurement. Continue to stand facing the right side of the SP. Do not stand behind the SP for this measurement. Wrap the measuring tape around the arm at the level of the upper arm mid-point mark. Position the tape perpendicular to the long axis of the upper arm. Pull the two ends of the overlapping tape together so that the zero end sits below the measurement value and the result lies on the lateral aspect of the arm (not the posterior surface). Check that the tape fits snugly around the arm but does not compress the skin. Exhibits 8 and 9 show the arm circumference measurement on an adult and infant, respectively. Take the measurement to the nearest 0.1 cm.
3. Record the Result. Call the result to the recorder, who will enter this number on the ISIS screen. Remove the tape measure. Proceed to the next circumference measure.
Exhibit 8. Adult arm circumference
Exhibit 9. Infant arm circumference
Personnel and Training Required
None
Equipment Needs
None
Requirements
| Requirement Category | Required |
|---|---|
| Major equipment | No |
| Specialized training | No |
| Specialized requirements for biospecimen collection | No |
| Average time of greater than 15 minutes in an unaffected individual | No |
Mode of Administration
Physical Examination
Lifestage
Infant, Toddler, Child, Adolescent, Adult, Senior
Participants
Participants aged 2 months or older
Selection Rationale
The National Health and Nutrition Examination Survey 2021-2023 protocols were selected as best practice methodology and are the most widely used protocols to assess mid-upper arm circumference.
Language
Chinese, English, Spanish
While the English version of this protocol has been updated, the available translations have not and reflect a previous version. These differences may impact the compatibility between the English and Spanish/Chinese versions. It is the responsibility of the investigator to determine if the translations are sufficiently compatible with the English version for their research and subsequent analysis.
Standards
| Standard | Name | ID | Source |
|---|
Derived Variables
None
Process and Review
The PhenX Steering Committee (SC) reviewed this protocol in October 2023. Guidance from the SC includes:
- Updated protocol
Protocol Name from Source
National Health and Nutrition Examination Survey (NHANES), Anthropometry Procedures Manual, 2021-2023
Source
Centers for Disease Control and Prevention, National Center for Health Statistics. National Health and Nutritional Examination Survey (NHANES) 2021-2023. Anthropometry Procedures Manual (Section 3.4.6 - Upper Arm Length and Section 3.4.7 - Arm Circumference). Hyattsville, MD: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention.
Detailed training videos are available from the CDC here: : www.youtube.com/watch?v=p9lwWPLvYpY
General References
Brahmbhatt, S. R., Brahmbhatt, R. M., & Boyages, S. C. (2001). Impact of protein energy malnutrition on thyroid size in an iodine deficient population of Gujarat (India): Is it an aetiological factor for goiter? European Journal of Endocrinology, 145(1), 11-17.
Trowbridge, F. L., & Staehling, N. (1980). Sensitivity and specificity of arm circumference indicators in identifying malnourished children. American Journal of Clinical Nutrition, 33(3), 687-696.
Waterlow, J. (1999). Treatment of children with malnutrition and diarrhoea. Lancet, 354(9185), 1142.
Yuksekkaya, H. A., Cakir, M., Tumgor, G., Baran, M., Arikan, C., Yagci, R. V., & Aydogdu, S. (2008). Nutritional status of infants with neonatal cholestasis. Digestive Diseases and Sciences, 53(3), 803-808.
Protocol ID
21102
Variables
Export Variables| Variable Name | Variable ID | Variable Description | dbGaP Mapping | |
|---|---|---|---|---|
| PX021102_Mid_Upper_Arm_Circumference_Length | ||||
| PX021102020100 | Distance from the spine extending from more | N/A | ||
| PX021102_Mid_Upper_Arm_Circumference_Measurement | ||||
| PX021102020300 | Arm circumference measured at the midpoint more | N/A | ||
| PX021102_Mid_Upper_Arm_Circumference_Midpoint | ||||
| PX021102020200 | Midpoint of the distance from the spine more | N/A | ||
| PX021102_Mid_Upper_Arm_Circumference_Side | ||||
| PX021102010000 | Arm used to measure mid upper arm circumference. | N/A | ||
Measure Name
Mid-Upper Arm Circumference
Release Date
September 16, 2024
Definition
Measurement of the circumference of the mid-upper arm
Purpose
Mid-upper arm circumference is a recognized and important anthropometric measure in children and in pregnant women to assess their nutritional status.
Keywords
Anthropometrics, nutrition, NHANES
Measure Protocols
| Protocol ID | Protocol Name |
|---|---|
| 21102 | Mid-Upper Arm Circumference |
Publications
There are no publications listed for this protocol.