Malnutrition suffers malnourished measurements

CEBU, Philippines - It had scared her as she watched children held up, placed on panty-like cribs while a health worker read the needle on the Salter Scale. “You’re next, Theresa,”  said the barangay health worker as she was held with both hands from her armpits and chest then placed on the crib. The worker squinted her eyes trying to make out the numbers and strained her neck as the scale was too high for her to read. She murmured numbers to her assistant who jotted it down. Theresa held on to the harness, as the weighing scale bobbed and the crib swung. She would have wanted to cry but the health worker took her out of the crib and placed her down. Today was Operation Timbang and children of ages 0 to five years queued to be weighed on a Salter scale.

The sun beat heavily as children waited for their turn. They thought about playing but that would have to wait until they were weighed. Mothers stayed under the shade with snacks ready when weighing was done.

From the Salter scale, four-year-old Theresa was led to a steel tape on the wall. Again the health worker measured her height and used cardboard aligned to the head of the child then read the numbers on the steel tape corresponding to the child’s height. After health workers tabulated and finalized their recording, it dismayed them that there were a considerable number of children who were underweight, that is, like Theresa whose weight was too low for her age. Others were severely wasted because their weight was too low for their height.

Right things, wrong way

All this time, nutrition and health workers may have been doing the right things in the wrong way. But dismay may only be the symptom of the real dilemma. What may have caused malnutrition are stunted statistics. All these years, there may have been discrepancies in nutritional status statistics owing to erroneous instruments and inaccurate measurement methods. Only last May 23 and 24, engineers from the Department of Science and Technology gave competency development training on the verification of wooden height boards and weighing scales to some 50 health and nutrition workers representing regions 6,7, 8 and 9. While the training was held in Cebu City, it is perhaps the first definitive move to rectify error ridden instruments and inaccurate measurement methods that may have caused and has been producing unreliable, highly erroneous child growth and nutritional status statistics over the years.

Meteorologists and engineers raised five major sources of errors in nutritional status statistics, including uncertain standards, tampered workpieces, faulty instruments, untrained persons and poor environment. In the absence of calibration and verification, all these can compromise accuracy. In some ways, malnutrition has become a statistical problem, not because of what is fed, rather because of uncalibrated instruments, inappropriate measurement paradigms and flawed methods of measurement.

What precipitated the competency training last May 23 and 24 was a 2012 National Nutrition Council resolution that ordered the expansion of Operation Timbang to the measurement of height for children two years older and the length of children less than two years. It used to be that the Operation Timbang measures child growth in terms of weight for age to determine whether or not a child is underweight and weight for height to determine wasting among children. Children who have low weight for height are considered severely wasted.

Under the 2012 resolution, the Operation Timbang Plus now requires height for age measurement to determine whether there is stunting. Hence children whose heights are short for their ages are considered stunted. There has been heightening concern on stunting after substantive evidence linked stunting to cognitive development and school performance. Because undernutrition impact brain development and impair motor skills, children who are stunted develop poor cognitive abilities into adult life which over time leads to diminished productivity. According to the Lancet’s Series on  “Maternal and Child Undernutrition,”  the best determinant of future capital is a child’s height-for-age at two years old. Because stunting is irreversible, children born with low birth weight face increased risk of chronic disease as adults. Thus, because the determinant of future capital is a child’s height-for-age, stunted children literally aggravate stunted economic growth.

To ensure the integrity of measurements for weight for age, weight for height and height for age, the National Nutrition Council Governing Board set guidelines for the fabrication, verification and maintenance of wooden height boards and weighing scales. In a its-never-too-late approach the NNC Governing Board set in motion the calibration and verification of instruments to generate more accurate child growth statistics especially for stunted, wasted and underweight. The accuracy of these statistics are critical in coming up with interventions and modifying nutrition management programs.

Health workers are not engineers.

Verification and calibration though necessitates training and with this, competency and empowerment among health workers. During the ensuing interaction, health workers raised concern that calibration and verification won’t be easy for health workers whose main tasks are welfare-based and service-oriented and not as meteorologists or engineers. Even if health workers do eventually understand the technicalities of calibration, their competency in a day-long training is not enough to make them licensed calibrators. The calibration and verification of weighing scales and height board needs licensed engineers and thus entail fees for calibration and verification.

For those in health care, calibration and verification of instruments are as critical as knowing what food supplement or micronutrients to administer. Inaccurate instruments beget inaccurate measurements begetting inaccurate results and hence inaccurate nutrition management interventions.

Engineer Paul Danniel P. Aquino of DOST said that calibration of measuring instruments is necessary because components of equipment age and undergo changes in temperature and mechanical stress that over time, can degrade or depreciate the equipment’s performance.  “This is called a drift,”  he said,  “When this happens, the test results generated by the equipment become unreliable and both design and production quality suffers. Drift affects the accuracy of the instrument.”

Aquino defined calibration as the comparison of measurements made by a standard instrument against a test instrument or the instrument to be calibrated. In calibration, the standard instrument must be better that the test instrument to insure accuracies in measurements. To maintain confidence in the calibration status of an instrument, it needs to be verified. Verification is the objective evidence that a given item fulfills specified requirements.

Because it was only last May 23 and 24 that there were definitive moves to calibrate height boards, steel rules and weighing scales, a disturbing thought gnaws the conscience: Could inaccurate OPT results have masked the real picture of nutrition status in this country all this time?

Nutrition Officer III Maria Cynthia B. Vengco said that Operation Timbang would have to go through a transition phase in using calibrated and verified weighing scales, steel rules and height boards before steel tapes and non-calibrated weighing scales are phased out.

Health and nutrition workers who participated in the competency training underscored the concern for local government support in the purchase of height boards, steel rules and weighing scales as well as budgets for calibration and verification. They also questioned the practicality of bringing the bulky height boards to mountain barangays especially that vulnerabilities to mistakes are high when steel rules and height boards are exposed to heat.

As the health worker slowly put down Theresa, the child walked to her mother who brought her a pack of chips and carbonated juice. After the weighing, comes the eating of junk food. But who cares, the weighing scale and steel tape weren’t calibrated anyway.