Child factor in measurement dependability

mHealth Improved Fruit and Vegetable Accessibility and Intake in Young Children

OBJECTIVE

To explore the potential of mHealth using smartphones to improve fruit and vegetable intake in children.

DESIGN

A 10-week randomized control and intervention pilot study.

SETTING

Story time sessions at local libraries.

PARTICIPANTS

A convenience sample of 30 parents and children (aged 3-8 years).

INTERVENTION

Delivery of nutrition intervention through the mobile Jump2Health website, Facebook posts, and text messages.

MAIN OUTCOME MEASURES

Electronic food photos of children's meals and snacks, 10-question survey related to fruit and vegetable consumption, reflectance spectroscopy via Veggie Meter to measure skin carotenoid levels, body mass index percentiles, and a mobile learning survey.

ANALYSIS

Descriptive statistics and Wilcoxon matched-pairs signed-rank test.

RESULTS

Veggie Meter values for children and parents showed significant week × treatment interactions in the intervention group compared with the control group for both children (P < .001 and parents (P < .001).

CONCLUSIONS AND IMPLICATIONS

This pilot study offers a potentially effective program including a mobile Web site, social media, and test message components to increase fruit and vegetable intake of young children.

Precision of recumbent crown-heel length when using an infantometer

BACKGROUND

Crown-heel length (CHL) measurement is influenced by technique, training, experience and subject cooperation. We investigated whether extending one or both of an infant's legs affects the precision of CHL taken using an infantometer. The influence of staff training and infant cooperation were also examined.

METHODS

CHL was measured in children (aged 2), infants (aged 1) and newborns, by extending one or both legs. The subject's level of cooperation was recorded. Mean differences were compared using Student's t-test; intra- and inter-observer variability were assessed using Bland-Altman plots with 95 % limits of agreement. Intra- and inter-observer technical errors of measurement (TEMs) were also calculated.

RESULTS

Measuring CHL in newborns using only one leg resulted in significantly longer measurements. Across all groups, there was less inter-observer variability using both legs; 95 % limits of agreement were lower and TEMs smaller. Larger measurement differences were seen if children were uncooperative.

CONCLUSIONS

This study supports measuring CHL with both legs extended. The two-leg technique reduces variability and increases precision by allowing the measurer to control better the position and movements of the infant's body.

Optimizing linear growth measurement in children

A child's pattern of linear growth is one of the most sensitive indicators of health and well-being. However, many health care personnel use casual techniques and faulty instruments to measure children's growth and keep imprecise growth charts, making interpretation of growth patterns problematic. This situation can delay diagnosis and treatment of children with growth disorders and other conditions that affect growth. It can also lead to undue anxiety and unnecessary evaluation of children who are actually growing well. A clinical practice guideline was developed to optimize the accuracy and reliability of linear growth measurement. This article presents strategies to implement the guideline and thereby increase awareness of the importance of standardized growth measurement techniques and instruments, facilitate staff training and competency, and encourage standardized record keeping. These strategies will give providers more confidence in their interpretation of children's growth patterns and allow them to recognize potential problems, possibly before other symptoms appear.

Prenatal and postnatal energetic conditions and sex steroids levels across the first year of life

OBJECTIVES

Human biologists have documented variability in reproductive maturation, fertility, and cancer risk related to developmental conditions. Yet no previous studies have directly examined the impact of prenatal and postnatal energetic environments on sex steroids in infancy, a critical period for hypothalamic-pituitary-gonadal axis development. Thus, we examined the impact of maternal characteristics, birth size, and feeding practices on fecal sex steroid production in a longitudinal sample of 31 American infants followed from 2 weeks to 12 months of age.

METHODS

Maternal characteristics and birth size were collected at study enrollment, infant diet was assessed through weekly 24-h food diaries, and anthropometrics were measured weekly. Fecal estradiol and testosterone levels were assessed weekly using validated microassay RIA techniques. Mixed models were used to test for associations between maternal and birth characteristics, feeding practices, and sex steroids across the first year of life. Formal mediation analysis examined whether the relationship between infant feeding and hormone levels was mediated by infant size.

RESULTS

Maternal and birth characteristics had persistent effects on fecal sex steroid levels, with taller maternal height and larger birth size associated with lower estradiol levels in girls and higher testosterone levels in boys. Infant diet was also associated with sex steroid levels independently of infant size. Formula feeding was associated with higher estradiol levels in boys and girls and with higher testosterone in girls.

CONCLUSION

These results suggest that markers of early energy availability influence sex hormone levels with potential long-term consequences for reproductive development and function.

Development of an evidence-based clinical practice guideline on linear growth measurement of children

Growth is an important indicator of child health; however, measurements are frequently inaccurate and unreliable. This article reviews the literature on linear growth measurement error and describes methods used to develop and evaluate an evidence-based clinical practice guideline on the measurement of recumbent length and stature of infants, children, and adolescents. Systematic methods were used to identify evidence to answer clinical questions about growth measurement. A multidisciplinary team critically appraised and synthesized the evidence to develop clinical practice recommendations using an evidence-based practice rating scheme. The guideline was prospectively evaluated through internal and external reviews and a pilot study to ensure its validity and reliability. Adoption of the clinical practice guideline can improve the accuracy and reliability of growth measurement data.

Infant head circumference growth is saltatory and coupled to length growth

BACKGROUND

Rapid growth rates of head circumference and body size during infancy have been reported to predict developmental pathologies that emerge during childhood.

AIMS

This study investigated whether growth in head circumference was concordant with growth in body length.

SUBJECTS

Forty infants (16 males) were followed between the ages of 2 days and 21 months for durations ranging from 4 to 21 months (2616 measurements).

STUDY DESIGN

Longitudinal anthropometric measurements were assessed weekly (n=12), semi-weekly (n=24) and daily (n=4) during home visits. Individual head circumference growth was investigated for the presence of saltatory patterns. Coincident analysis tested the null hypothesis that head growth was randomly coupled to length growth.

RESULTS

Head circumference growth during infancy is saltatory (p<0.05), characterized by median increments of 0.20 cm (95% confidence interval, 0.10-0.30 cm) in 24-h, separated by intervals of no growth ranging from 1 to 21 days. Daily assessments identified that head growth saltations were coupled to length growth saltations within a median time frame of 2 days (interquartile 0-4, range 1-8 days). Assessed at semi-weekly and weekly intervals, an average 82% (SD 0.13) of head growth saltations was non-randomly concordant with length growth (p≤0.006).

CONCLUSIONS

Normal infant head circumference grows by intermittent, episodic saltations that are temporally coupled to growth in total body length by a process of integrated physiology that remains to be described.

Infant growth in length follows prolonged sleep and increased naps

STUDY OBJECTIVES

The mechanisms underlying infant sleep irregularity are unknown. This study tests the hypothesis that sleep and episodic (saltatory) growth in infant length are temporally coupled processes.

STUDY DESIGN

Daily parental diaries continuously recorded sleep onset and awakening for 23 infants (14 females) over 4-17 months (n = 5798 daily records). Multiple model-independent methods compared day-to-day sleep patterns and saltatory length growth.

MEASUREMENTS AND RESULTS

Approximate entropy (ApEn) quantified temporal irregularity in infant sleep patterns; breastfeeding and infant sex explained 44% of inter-individual variance (P = 0.001). Random effects mixed-model regression identified that saltatory length growth was associated with increased total daily sleep hours (P < 0.001) and number of sleep bouts (P = 0.001), with breastfeeding, infant sex, and age as covariates. Infant size and illness onset were non-contributory. CLUSTER analysis identified peaks in individual sleep of 4.5 more h and/or 3 more naps per day, compared to intervening intervals, that were non-randomly concordant with saltatory length growth for all individuals (P < 0.05), with a time lag of 0-4 days. Subject-specific probabilities of a growth saltation associated with sleep included a median odds ratio of 1.20 for each additional hour (n = 8, 95% CI 1.15 to 1.29) and 1.43 for each additional sleep bout (n = 12, 95% CI 1.21-2.03). Increased sleep bout duration predicted weight (P < 0.001) and abdominal skinfold accrual (P = 0.05) contingent on length growth, and truncal adiposity independent of growth (P < 0.001).

CONCLUSIONS

Sleeping and length growth are temporally related biological processes, suggesting an integrated anabolic system. Infant behavioral state changes may reflect biological mechanisms underlying the timing and control of human growth.

Challenges of accurately measuring and using BMI and other indicators of obesity in children

BMI is an important indicator of overweight and obesity in childhood and adolescence. When measurements are taken carefully and compared with appropriate growth charts and recommended cutoffs, BMI provides an excellent indicator of overweight and obesity that is sufficient for most clinical, screening, and surveillance purposes. Accurate measurements of height and weight require that adequate attention be given to data collection and management. Choosing appropriate equipment and measurement protocols and providing regular training and standardization of data collectors are critical aspects that apply to all settings in which BMI will be measured and used. Proxy measures for directly measured BMI, such as self-reports or parental reports of height and weight, are much less preferred and should only be used with caution and cognizance of the limitations, biases, and uncertainties attending these measures. There is little evidence that other measures of body fat such as skinfolds, waist circumference, or bioelectrical impedance are sufficiently practicable or provide appreciable added information to be used in the identification of children and adolescents who are overweight or obese. Consequently, for most clinical, school, or community settings these measures are not recommended for routine practice. These alternative measures of fatness remain important for research and perhaps in some specialized screening situations that include a specific focus on risk factors for cardiovascular or diabetic disease.

Sex differences in the relationships among weight gain, subcutaneous skinfold tissue and saltatory length growth spurts in infancy

As the mechanisms controlling the amount and timing of growth saltations are not well understood, the identification of physiologic coupling in weight and length growth are important for further understanding normal growth biology. Thirty-four healthy infants (13 males, 21 females) participated in a longitudinal growth study during the first year. Weekly weights and s.c. skinfolds (limb and trunk) were analyzed in a growth event-focused study. Coincident analysis tested the null hypothesis of chance concurrence between significant weight gain and saltatory length growth spurts. Logistic regression quantified this relationship and investigated the interaction between incremental weight gain and s.c. skinfolds on length growth spurts. The null hypothesis of random coincidence between weight gain and saltatory length growth was not supported. For girls, significant weight gain and length growth were coupled during the same week and length saltations were 42% more likely during the weeks of significant weight gain, with no interaction from s.c. skinfolds. For boys, length growth saltations were coupled to both previous and concomitant weight gain but were predicted only by previous weight gain, controlling for confounders. Boys were 68% more likely to grow in length the week following significant weight gain, and initial abdominal to suprailiac skinfold ratios conferred a 4-fold increased likelihood of length growth within the week, controlling for confounders. These data generate the hypothesis that a common growth signal cascade couples growth in weight and length/height with a time delay due to sex-specific biology, reflected in a s.c. fat fold interface.

Childhood overweight in a New York City WIC population

OBJECTIVES

We estimated the prevalence of overweight in a population of young children enrolled in a New York City Special Supplemental Nutrition Program for Women, Infants, and Children.

METHODS

Administrative and survey data were collected from a sample of enrolled families. Body mass index (BMI) of 557 children aged 2, 3, and 4 years was compared by sociodemographic and nutrition characteristics.

RESULTS

Forty percent of the children were overweight or at risk for overweight (BMI >/= 85th percentile). Compared with other racial/ethnic groups combined, Hispanic children were more than twice as likely (odds ratio = 2.6; 95% confidence interval = 1.8, 3.8) to be overweight or at risk for overweight. Two-year-olds were less likely to be overweight than 3- and 4-year-olds.

CONCLUSIONS

Interventions to address childhood overweight should be culturally specific and target very young children.