The overall goal of these techniques are to obtain accurate manual anthropometric measurements using inexpensive and portable equipment. The accurate assessment of anthropometry is essential for understanding the health effects for growth and adiposity. And these measurements can be obtained using inexpensive and portable equipment.
The main advantage of these techniques is that manual anthropometric measures can be performed in most field settings at a reasonable cost. At Project Viva, a pre worth cohort study, we have standardized and refined our anthropometry protocol training and quality control procedures over the last 17 years. Visual demonstration of this measurement is essential for indicating proper anatomical measurement sites, hand placements, and posture, because even minor variations in these can affect the accuracy of the measurements.
Demonstrating the procedures will be Marleny Ortega, Research Associate, and Nicole Witham, Operations Coordinator from the Project Viva team. Before beginning the assessments, have the participant dress in lightweight clothing that allows easy access to the extremities and torso while maintaining modesty. For a standing height assessment, guide the participant back onto the stadiometer board until the buttocks, shoulder blades, back of head, or heels make contact with the board.
Instruct the participant to stand as straight as possible without slouching or leaning, and with the feet flat and the arms hanging straight down on the sides. Confirm that the weight is evenly distributed between the left and right sides of the body. Then visually verify that the mid axillary line is parallel to the back of the board.
Now looking at the side of the participant's head, position the head so that an imaginary line from the lowest margin of the eye orbit to the highest margin at the opening of the ear canal is parallel to the floor. With the participant standing straight and tall, position the headpiece firmly on top of the head with sufficient pressure to compress the hair and to make contact with the skull. Then with the headpiece at eye level, take the measurement to the nearest tenth of a centimeter.
For the sitting height assessment, place the stadiometer on top of a stool tall enough to allow the participant's legs to form a 90 degree angle with the ground. Ensure that the participant is sitting as erectly as possible. With the buttocks, shoulders, or head touching the back of the board, the knees directly in front of the body, and the hands on the thighs.
Confirm that the mid axillary line is parallel to the stadiometer. Place the participant's head into the Frankfort plane. Then with the headpiece firmly on top of the participant's head, obtain a measurement to the nearest tenth of a centimeter, while directly facing the measurement index at eye level.
For assessment of the waist circumference, have the participant stand erect, lateral to a chair, with the arms crossed in front holding up the shirt. Sit at the side of the participant with the hip bone at eye level. Then compress the skin at the presumed location of the hip bone, using anatomical visuals as a guide, and identify the anterior part of the hip bone.
To verify placement, have the participant lean on a coronal plane, activating the hip joint. If you have properly identified the iliac crest, your fingers will skim to the top of the iliac crest as the participant leans in your direction. Help it upward along the bone to locate the iliac crest, until the imaginary intersection between the uppermost point of the iliac crest and the mid axillary line is reached.
Identify the site with a self-adhesive sticker, and repeat the site identification on the other side. With the participant standing perpendicular to the mirror, gently place the measuring tape around the waist on top of the two stickers, using the mirror as a guide to adjust the tape so that it is on a level horizontal plane across the front, back, and both sides of the participant. When the tape is in place, tighten it so that the skin is pinched slightly.
Then slowly loosen the tape to form a smooth surface on the skin, so that the skin is no longer constricted, but free of gaps in the tape measure. At the end of the participant's natural exhalation, read the tape to the nearest tenth of a centimeter. To measure the hip circumference, place the measuring tape around the hips, anchoring the tape at the maximum protuberance of the buttocks.
Holding the tape measure firmly and flatly, adjust the tape so that it is on a horizontal plane around the body, and read the measurement to the nearest tenth of a centimeter. To measure the mid upper arm circumference, instruct the participant to lift one shirtsleeve to shoulder height, and to position the arm so that it is flexed at a 90 degree angle at the elbow, with the palm facing up and the fingertips pointing straight ahead. Standing behind the participant, locate the posterior lateral shoulder bone connecting the participant's shoulder blade and clavicle, and extend the tape down the midline of the back of the arm to the bony tip of the elbow.
Use the tape to measure the distance between the acromion process and the olecranon to the nearest tenth of a centimeter, and place a sticker halfway between the olecranon and the acromion process over the posterior center of the humerus. Standing to the right and slightly behind the participant, move the participant's arm slightly away from the body so that the muscles are relaxed. Using a small flip tape, slide the tape to the upper arm so that it covers the sticker.
Then pull the tape so that there are no gaps in the tape or areas of the skin constriction to obtain a measurement to the nearest tenth of a centimeter. To assess the triceps skin thickness, use the sticker at the posterior midpoint of the upper arm to identify a location approximately two centimeters above the sticker. Standing behind the participant, grasp a sizable fold of skin between the thumb and index finger about one to two centimeters into the skin.
Roll the skin between your fingers, identify the point at which the fleshy, flexible part of the fold connects to a firm surface. This is a point at which fat met muscle. Obtain only fat in the skin fold.
While holding the skin fold parallel to the arm, place the skin fold caliper jaw perpendicular to the length of the fold on either side of the marked midpoint. Now completely release the grip on the caliper level while continuing to hold the skin in between the caliper jaws for four full seconds, after which time the skin should be fully compressed, and record the measurement to the nearest two tenths of a centimeter. To measure the subscapular skin fold thickness, palpate the lowermost tip of the scapula to locate the measurement site two centimeters below the lower tip of the scapula.
Grasp a sizable fold of skin between the thumb and index finger on a diagonal, approximately two centimeters above and to the left of the measurement site. Place the calipers on the skin fold at the measurement site so that the fold is parallel to the medial inferior bone of the scapula. Completely release the grip on the caliper level, recording the thickness to the nearest two tenths of a centimeter after four seconds.
Here, representative inter-rater technical error of measurement values from a quality control session conducted by six research assistants on five healthy adult female volunteers are shown. These values fell within the range of acceptability for each measure, indicating a low variability between the measurements and thus an accurate technique. With the least precise measurements overall obtained for the skin fold thickness assessments.
In this figure, all of the height measurements obtained at the quality control session are plotted. Most of the height measurements are within one centimeter of each other. With several outlying measurements indicating a need for more training for the researchers who took these measurements.
The research staff members experienced a greater inter-rater reliability for the subscapular skin fold thickness measurements than for the height measurements. In our study of 1100 Project Viva participants, ages 6.5 to 10.9 years, manual anthropometric measures including the weight, waist circumference, and some of the triceps and subscapular skin fold thicknesses were highly correlated with the adiposity measures obtained by a dual-energy x-ray absorptiometry machine, commonly used as a body fat measurement gold standard. Following this procedure, similar methods like recumbent length and other skin fold measurements can be performed in field settings with minor alterations to answer additional questions about the predictors and health effects of child growth.
After watching this video, you should have a good understanding of how to conduct accurate anthropometric measures. Using these standardized procedures, obtaining accurate and precise measurements is possible with adequate training and attention to quality control.
