New York, May 27 (IANS): Measuring the circumference of the arm of children can lead to better diagnosis of malnutrition than weight-based measurements, says a study.

Using a measuring tape to measure arm circumference is the most reliable factor in diagnosing malnutrition, said Adam Levine, emergency medicine physician at the Rhode Island Hospital in the US.

Measuring tapes are inexpensive and readily available in resource-limited environments.

The traditional measure for determining whether a child is moderately or severely malnourished is based on evaluating the child's weight directly.

"Dehydration lowers a child's weight, using weight-based assessments in children introduced with diarrhoea may be misleading," Levine said.

"When children are rehydrated and returned to a stable, pre-illness weight, they may still suffer from acute malnutrition."

About half a million children die annually from severe malnutrition and nearly 100 million children are underweight, mostly in the world's poorest countries.

Diarrhoea is common among children who visit health facilities in developing nations.

Levine and his team studied the clients of an urban hospital in Dhaka, Bangladesh.

They analysed 721 records of all children under 60 months of age who visited the hospital's rehydration unit with acute diarrhoea.

They found that 12-14 percent of children were misclassified with malnutrition using weight-based measures compared to only one-two percent who were measured by arm circumference.

The study was published in the Journal of Nutrition.