Digitized by Kansas Correctional Industries

Thesis (M.Sc. (Biostatistics))--Mahidol University, 1984.

Thesis (M.S.)--Marshall University, 2002. / Title from document title page. Document formatted into pages; contains vii, 46 p. Includes bibliographical references (p. 43-46).

Background: Fat distribution, rather than total body fat, has been identified as a significant risk factor for chronic disease. Patterning of subcutaneous fat, in particular, may play a pervasive role in shaping the metabolic milieu that is critical for disease development. Several studies have shown that early-life nutrition may influence later body composition. The effect of breastfeeding and formula feeding on early patterns of subcutaneous fat deposition, however, are uncertain. Objective: At a time when early infant growth is emerging as a predictor for later chronic disease, it is the aim of the present analysis to investigate whether feeding style (breastfeeding versus formula feeding) modifies subcutaneous fat growth rates and trajectories in the first year of life with a focus on the historical iterations of WHO infant feeding recommendations (0 to 4 months, 4 to 6 months, and 6 to 12 months of age). Methods: This is an ex post-facto design that utilizes data collected as part of a longitudinal growth study in the first year of life. Subcutaneous fat mass was anthropometrically assessed weekly by skinfold thickness (triceps, quadriceps, calf, subscapular, suprailiac, midaxillary, and abdominal) in 21 infants. Feeding data were collected through daily parental records and are entered here as a categorical variable (predominantly breast fed and predominantly formula fed). Multi-level mixed effects models for repeated measures were used (STATA 14) adjusting for age, sex, weight, birthweight, and number of feeding episodes per day. Statistical significance was accepted at p Results:Infants experienced fat accretion only during the first four months, and this was limited to peripheral skinfolds. Thereafter, subcutaneous skinfolds followed a trend of declining rates. Breastfed and formula fed infants, however, demonstrated different patterns of subcutaneous fat deposition in both the sum of skinfolds and in each skinfold site. During the first four months, formula fed infants experienced greater rates for the subscapular, abdominal, suprailiac, trunk, quadriceps, sum of skinfolds (p Conclusion: Weekly skinfold assessments of seven subcutaneous sites have identified that feeding style predicts differences in deposition patterns in the first year of life. Breastfed infants demonstrated both slower rates of accretion and decline by comparison with their formula fed peers. This analysis further suggests that the first four months may be a critical period for subcutaneous fat deposition. Feeding specific effects were identified for truncal deposition and utilization, which suggests that future studies may benefit from depot-specific inquiries.

No description available.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

Thesis (Ph. D.)--University of New Mexico, 2002. / Includes bibliographical references (leaves 80-90). Also available online (PDF file) by a subscription to the set or by purchasing the individual file.

Thesis (Ph. D.)--University of New Mexico, 2002. / Includes bibliographical references (leaves 80-90).

No description available.

The purpose of this study was to determine the validity and reliability of four methods of estimating body composition in 331 participants (177 boys, 154 girls) between 12-17 years of age. Percent body fat (%BF) was assessed once on one day using DEXA and twice using the sum of two skinfold (SF) and three bio-electrical impedance analysis (BIA) devices: OMRON hand-to-hand BIA, TANITA 521 foot-to-foot BIA, and TANITA 300A foot-to-foot BIA. The same assessments were repeated on 79 of the participants on a second day. DEXA was used as the criterion method of estimating %BF. The agreement between the estimates of %BF from the sum of two SF and the three BIA devices and DEXA was evaluated using linear regression and Bland-Altman analyses. Although the two analyses generally led to similar conclusions about each of the four prediction methods, the specific interpretations of each analysis varied because of the inherent differences in the analyses. In an attempt to determine if any of the four prediction methods were interchangeable with DEXA, the 95% confidence interval (CI) and prediction interval (PI) around the line-of-best-fit through the data are reported. The results of this study indicate that (a) all of the methods used in this study to estimate %BF were reliable within and between days, (b) the TANITA 300 BIA device performed poorly in both boys and girls and should not be used to assess body composition in children and adolescents, (c) none of the four prediction methods performed well in both boys and girls across the entire range of %BF values of the subjects in this study, (d) the sum of two SF, OMRON and TANITA 521 are acceptable for use in large population-based studies but are not recommended when the accurate assessment of body composition of an individual is critical, in which case (e) criterion methods of assessing body composition should be used.