Abstract:
The longitudinal growth of individual's stature of the present study was
characterized from early childhood to adulthood. The samples used here were 509 males
and 311 females. A triphasic generalized logistic model (BTT model) and diphasic
growth model (JPA-2 model) applied respectively on the above two sets of data through
the software AUXAL for characterizing individual growth of stature. The default values
of the population mean and covariance matrix in AUXAL for both the models were
substituted by estimated population mean and covariance matrix based on Japanese
population. The individuals without mid growth spurt for both sexes show that predicted
adult stature (PAS) was significantly positive correlated with stature at onset of
adolescent and adolescent growth phases, and for only girls VTO and PHV was
positively correlated. The individuals with mid growth spurt for both sexes show that
PAS was significantly positively correlated with statures at early childhood minimum,
mid-childhood maximum, onset of adolescent and adolescent growth phases. Also
positive significant correlations were found between VECM and VMC, VTO and PHV
but in case of PHV and VMC, negative significant correlation was found. On the basis of
JPA-2 model the mean adult stature were 171.27cm for Japanese boys and 158.51 for
Japanese girls. On the basis of BTT model this study demonstrates that, on average,
46. 1 %, 39.5%, and 14.4% of the total adult stature were completed during early, middle
and adolescent phase of growth, respectively, for the Japanese male population. For the
female population, these percentages were 42.6%, 44.6%, and 12.8%, respectively. The
distributions of predicted stature that do not have the mid growth spurt, on average,
shows that the Japanese girls become taller than boys from age 1 to 5 and 10 to 12, and
then again become shorter than boys. The distributions of predicted stature that have the
mid growth spurt, on average, shows that the Japanese girls become taller than boys from
age 8 and 11 to 12, and then again become shorter than boys. Japanese boys who do not
have the mid growth spurt are, on average, 13.26 cm taller than their opposite sex.
Moreover, Japanese boys who have the mid growth spurt are, on average, 13. 77 cm taller
than their opposite sex.
Several equations, after removing the problem of outliers and influential data
points, are proposed to predict the adult stature of the Japanese based on growth
parameters and statures at different ages.
Description:
This Thesis is Submitted to the Department of Statistics, University of Rajshahi, Rajshahi, Bangladesh for The Degree of Doctor of Philosophy (PhD)