[Critical analysis of the validity of arm circumference as an indicator of protein-energy nutritional status in preschool children].

Arm circumference has been recommended as a useful indicator for malnutrition screening, particularly in rural areas. The great advantages of the arm circumference over other anthropometric indicators are that the measure is easily obtained in rural areas and that the method for assessing arm circumference is simple, inexpensive and rapid. In this paper the validity (specificity and sensitivity) of arm circumference is analyzed as compared to more valid indicators of nutritional status in preschool children. We conclude that arm circumference is relatively valid for detecting global malnutrition (as indicated by weight-for-age), but of limited validity when used for detecting acute or chronic protein-calorie malnutrition. Furthermore, when compared to weight-for-age in detecting populations or individuals at high risk of acute or chronic protein-calorie malnutrition, it was found that weight-for-age has a higher level of specificity and sensitivity than arm circumference. Finally, it was found that sensitivity and specificity of arm circumference vary with age, suggesting that arm circumference cannot be considered an age-independent indicator of nutritional status. It is therefore recommended that these possible limitations of arm circumference be kept in mind when used in public health programs.