Mid-upper-arm circumference (MUAC) based on a single cut-off value for all children under 5 years of age has been used for many years as an alternative nutritional status index for children during famines or refugee crises, and as an additional screening tool in nonemergencies. However, it has recently been questioned whether MUAC is age- and sex-independent. After reviewing the scientific evidence underlying the use and interpretation of MUAC, a WHO Expert Committee recommended a new MUAC-for-age reference for under-5-year-olds. In some settings, however, it is difficult to assess a child's age and in such circumstances MUAC-for height may be a good alternative. The height-based QUAC stick offers a simple means of adjusting MUAC cut-offs according to height, and the MUAC-for-height reference and construction and use of the QUAC stick are described in this article. Also described is the use of the receiver operating characteristic (ROC) curve method to evaluate the performance of MUAC, MUAC-for-age, and MUAC-for-height in screening malnourished children.

Durante muchos años se han usado los valores de perímetro braquial inferiores a cierto límite como índice alternativo del estado nutricional de los menores de 5 años de edad en épocas de hambruna o crisis de refugiados y también como método adicional de tamizaje en situaciones normales. Sin embargo, recientemente se ha puesto en duda la independencia del perímetro braquial respecto de la edad y el sexo. Tras revisar las pruebas científicas en las que se basan el uso y la interpretación del perímetro braquial, un Comité de Expertos de la OMS recomendó nuevos valores de referencia de perímetro braquial según la edad en menores de 5 años. Sin embargo, en algunas situaciones es difícil evaluar la edad de un niño y en tales circunstancias el perímetro braquial según la altura puede ser una buena alternativa. La regla QUAC (del inglés Quaker arm circumference) para medir la altura es un medio sencillo para determinar el punto de corte del perímetro braquial correspondiente a una altura dada. Este artículo describe los valores de referencia del perímetro braquial y la construcción y uso del medidor QUAC, así como la utilización del método de curvas de características funcionales (receiver operating characteristic curve) para evaluar el rendimiento del perímetro braquial, el perímetro braquial según la edad y el perímetro braquial según la altura en la detección de niños malnutridos.

Objective To better characterize childhood growth and further assess potential limitations of the current National Center for Health Statistics and World Health Organization international growth reference. Design The LMS method was used for curve fitting to summarize the changes in height and weight distributions by 3 curves representing the skewness (L), median (M), and coefficient of variation (S). A series of polynomial regression procedures was applied to smooth the L, M, and S curves. Setting Subset data from 18 states contributing clinic data to the Centers for Disease Control and Prevention Pediatric Nutrition Surveillance System were used for this research reference. Methods We chose only those clinics in which the height and weight distributions of children closely matched with those of the first and second National Health and Nutrition Examination Surveys. Results Unlike the current international growth reference, the new reference has no disjunction at 24 months of age because it is based on a single data source for children aged 0 to 59 months. The reference also better characterizes the growth for infants than the current international reference, a fact we demonstrated with data from the National Health and Nutrition Examination Surveys, Pediatric Nutrition Surveillance System 1995, and the Davis Area Research on Lactation, Infant Nutrition, and Growth studies. Conclusions The current National Center for Health Statistics and World Health Organization international growth reference needs to be updated. The methods used in this study will be useful to evaluate other data sets and to evaluate future modifications of growth references.

The current international growth reference, the National Center for Health Statistics (NCHS) reference, is widely used to compare the nutritional status of populations and to assess the growth of individual children throughout the world. Recently, concerns were raised regarding the adequacy of this reference for assessing the growth of breast-fed infants. We used the NCHS reference to evaluate infant growth in one of the most developed areas of Brazil. Infants who were exclusively or predominantly breast-fed for the first 4–6 mo, and partially breast-fed thereafter, grew more rapidly than the NCHS reference in weight and length during the first 3 mo, but appeared to falter thereafter. The average growth of all infants, regardless of feeding pattern, was faster than the NCHS reference until ∼6 mo, after which their growth became slower than that of the NCHS sample. To substantiate this finding, the NCHS growth curves were then compared with growth data of breast-fed infants in developed countries from pooled published studies, formula-fed North American and European infants and predominantly bottle-fed U.S. infants monitored by the Centers for Disease Control and Prevention (CDC) Pediatric Surveillance System. In all three cases, weights showed the same pattern as the Brazilian infants—higher than NCHS in the early months but an apparent decline thereafter. The pattern for length gain was similar but less marked. Breast-fed infants showed more pronounced declines than those who were predominantly bottle-fed. These findings suggest that the infancy portion of the NCHS reference does not adequately reflect the growth of either breast-fed or artificially fed infants. This probably results from characteristics of the original sample and from inadequate curve-fitting procedures. The development of an improved international growth reference that reflects the normal infant growth pattern is indicated.

Low mid-upper-arm circumference (MUAC), determined on the basis of a fixed cut-off value, has commonly been used as a proxy for low weight-for-height (wasting). The use of a fixed cut-off value was based on the observation that MUAC showed small age- and sex-specific differences. However, in 1993, a WHO Expert Committee concluded that age independence is not reflected in the true pattern of mid-upper arm growth, recommended the use of MUAC-for-age, and presented age- and sex-specific MUAC reference data developed with observations obtained from a representative sample of children in the USA aged 6-59 months. In this article, we explain the methodology for the development of these data, present age- and sex-specific growth curves and tables and discuss the applications and limitations of MUAC as a nutritional indicator. To develop the reference data, estimates were first obtained for the mean and standard deviation of MUAC for each month of age using 7-month segmental regression equations; a 5th-degree and a 3rd-degree polynomial in age was then used to describe the mean and standard deviation, respectively, of MUAC-for age. These curves show important age-specific differences, and significant sex-specific differences for boys and girls < 24 months of age. Correct interpretation of MUAC with regard to nutritional status requires the use of MUAC-for-age reference data such as those presented here.

Mid-upper-arm circumference (MUAC) based on a single cut-off value for all the children less than 5 years of age has been used for many years as an alternative nutritional status index for children during famines or refugee crises, and as an additional screening tool in nonemergencies. However, it has recently been questioned whether MUAC is age- and sex-independent. After reviewing the scientific evidence underlying the use and interpretation of MUAC, a WHO Expert Committee recommended a new MUAC-for-age reference for under-5-year-olds. In some settings, however, it is difficult to assess a child's age and in such circumstances MUAC-for-height may be a good alternative. The height-based QUAC stick is a simple means of adjusting MUAC cut-offs according to height, and the MUAC-for-height reference and the construction and use of the QUAC stick are described in this article. Described also is the use of the receiver operating characteristic (ROC) curve method to evaluate the performance of MUAC, MUAC-for-age, and MUAC-for-height in screening malnourished children.

Four issues in the use and interpretation of anthropometry are discussed at the level of the population and of the individual. The first issue is the index or indices of choice: weight-for-height versus height-for-age versus weight-for-age. The selection of an index or indices depends upon many factors, and no one index is completely adequate in all situations. Proposed criteria are provided to assess the severity of low anthropometry within populations. The second issue is the scale of the index: z-scores (or standard deviations) versus percentiles versus percent-of-median. z-Scores have several properties that make them superior to the other two scales. A third issue deals with limitations in the current growth reference; one of these is the disjunction between the growth curves at 2 years of age, resulting from the use of two different populations in the reference. It is important that this disjunction be recognized by researchers so that the anthropometric findings are interpreted correctly for this age range. Lastly, some issues to do with the collection of single versus multiple anthropometric measurements on children are discussed.

To better define the trends and patterns of growth for low-income children, we studied the anthropometry data collected by the second National Health and Nutrition Examination Survey (NHANES II) and the CDC Pediatric Nutrition Surveillance System (PNSS). Based on NHANES II, we found that low-income children appear to have a greater prevalence of shortness (low height-for-age), but do not have a greater prevalence of overweight (high weight-for-height) when compared with children from higher income families. Based on 12 states that were monitored continuously by the PNSS from 1980 to 1989, low-income children under 5 years of age appear to have a stable trend of height and weight status, with the exception of Asian children, most of whom were from Southeast Asian refugee background, showed a dramatic improvement in height status. However, based on PNSS data for the years 1977 to 1990 from Louisiana and Michigan, school-aged children and adolescents appear to have become slightly taller as well as having significant increases in body weight in relation to height. An additional investigation is needed to verify this trend of increasing excess weight among older, low-income children.

Although levels of coagulation factor VII and fibrinogen are predictive of cardiovascular disease, relatively little data describe hemostatic characteristics in healthy populations. The cross-sectional associations between the prothrombin time, a measure of the activity of the extrinsic and common pathways of coagulation, and traits associated with the risk of cardiovascular disease were therefore examined among 3,604 white and 514 black, male, US Army veterans aged 31-45 years. The prothrombin time measurements, performed in 1985 and 1986, were precise, with an intraclass correlation of 0.98 (202 pairs). Overall, the mean prothrombin time was 12.4 seconds (standard deviation, 0.4 seconds), and 11 percent of the men had a value of less than 12 seconds. Many of the observed associations with the prothrombin time paralleled those that have been reported with clotting factor VII and fibrinogen. The mean prothrombin time was 0.15 seconds shorter among whites than among blacks and was 0.2 seconds shorter among current cigarette smokers than among men who had never smoked. Inverse associations were also seen with relative weight and with levels of total cholesterol and triglycerides (r = -0.09 to -0.16). All associations were statistically significant at the 0.01 level, and the examined characteristics could jointly account for about 12 percent of the variability in prothrombin times. Additional data on characteristics related to coagulation may help elucidate the natural history of cardiovascular disease and aid in the design of clinical trials.

The CDC Pediatric Nutrition Surveillance System (PedNSS) monitors the general health and nutritional characteristics of low-income U.S. children who participate in multiple public health programs. This system is intended to characterize trends and patterns in key indicators of nutritional status so that the information can be used for program planning and targeting. The indicators monitored by PedNSS are birth weight, childhood growth status, anemia, and breast-feeding patterns. From 1980 through 1991, the trends for low birth weight, low height-for-age (shortness), low weight-for-height (thinness), and high weight-for-height (overweight) were stable for all children monitored by the PedNSS, with the exception of Asian children, who were predominantly of Southeast Asian refugee background. In the early 1980s, the prevalence of low birth weight and shortness was higher among Asian children than among children of other racial or ethnic groups who were monitored by the PedNSS. However, these prevalences declined steadily from 1980 through 1991. By 1991, the prevalences of low birth weight and shortness for Asian children were similar to those observed for children of other races/ethnic groups. Overall, low-income U.S. children had a slightly lower height-for-age than expected, indicating that some of these children were at a health and nutritional disadvantage. The prevalence of overweight varied among different racial/ethnic groups; Hispanic and Native American children had the highest prevalences of overweight. The 20%-30% prevalence of anemia among low-income children monitored by the PedNSS was higher than among the general population, reflecting in part the preferential enrollment and retention of anemic children by public health nutrition programs and also indicating that many children had inadequate iron nutrition. From 1980 through 1991, the prevalence of anemia declined > 5% for most of the age- and race/ethnicity-specific groups monitored by PedNSS. That decline represents an improvement in iron nutritional status. PedNSS is a useful system for the monitoring and characterization of the nutrition status of low-income children at both state and national levels.

Since 1979, the CDC Pregnancy Nutrition Surveillance System (PNSS) has monitored behavior and nutritional risk factors among low-income pregnant women participating in public health programs. Although the states contributing to the system have varied over the period, the PNSS is able to characterize the behavior and health outcomes of pregnant women from diverse low-income populations. In 1990, 66.2% of the women in the system initiated prenatal care during the first trimester of pregnancy; 26.4% smoked during pregnancy. Since 1979, the prevalence of smoking remained relatively stable for white women, but declined for blacks and Hispanics. Prepregnancy body mass index (BMI, defined as kg/m2) showed marked changes from 1979 through 1990; the prevalence of underweight (BMI < 19.8) declined steadily and the prevalence of overweight (BMI > 26) increased steadily. In 1990, 39.3% of the women had gestational weight gains below levels recommended by the National Academy of Sciences. Both prepregnancy underweight and inadequate gestational weight gain were associated with greater risk for low birth weight in the PNSS. The prevalence of anemia at each trimester has remained stable since 1979. In 1990, 9.8%, 13.8%, and 33% of the women reported by the PNSS were anemic in the first, second, and third trimesters, respectively. Anemia in the first trimester appeared to be strongly associated with a high risk of low birth weight; this association was attenuated in later trimesters. These findings indicate the need to improve iron nutrition among low-income women.

Objective. - To analyze the trend and pattern of the nutrition status of Southeast Asian refugee children and other low-income children in the United States.Design. - Descriptive analysis of the growth data from the Pediatric Nutrition Surveillance System of the Centers for Disease Control, Atlanta, Ga, from 1980 through 1989.Subjects. - Children under 5 years of age from low-income families enrolled in public health clinics in 12 selected states.Measurements and Main Results. - Asian refugee children experienced a progressive and significant decline in the prevalence of low birth weight, low height-for-age, and low weight-for-age, while these nutritional indexes remained stable for low-income white, black, and Hispanic children. By 1989, the growth status of Asian children was near that of other ethnic groups.Conclusions. - The marked improvement of growth status among Asian refugee children over a short period suggests that the poor growth status often observed among recently immigrated Asian children is primarily related to nutritional and health factors, rather than genetic factors. In assessing the growth of Asian or immigrant children, it would be helpful to take their family and early childhood background into account.

Public health nutrition programs are intended to serve low-income families who are at greater nutritional risk than the general population. Not all persons who are program-eligible are at equal risk, however. It would be desirable to evaluate a program's ability to enroll persons from higher risk backgrounds in the population (coverage) and, conversely, the extent to which those enrolled in this program are at higher risk (targeting). A method for the evaluation of coverage and targeting was developed using data from the Tennessee Women, Infants, and Children Special Supplemental Food Program (WIC) linked with birth certificates. The linked computer file was created by matching the name and date of birth in both record files. The birth records were the common source of information used to characterize the risk background for both the WIC and non-WIC participants. Maternal sociodemographic information on the birth records was used to define the health risk background of each child. The coverage and targeting of "at-risk" children were computed and compared for 50 counties or county-aggregates in Tennessee. Considerable variation in the coverage and targeting rates of at-risk children was observed among Tennessee counties, although the counties within each WIC administrative region tended to have similar coverage and targeting patterns. Using the existing data in linked program and vital records provides a direct evaluation of a program. Coverage and targeting evaluation can be used to detect underserved populations within small geographic areas.