Growth Charts Flashcards
if there is unsymmetrical distribution would you call the middle line the mean
no median
what is standard deviation
measure of variability
what is the Z score
the standard deviation score- the number of SD a result is from the mean
how many standard deviations will create a 95% reference rate
2sd
If there are 100 people measured, how many are within 1 SD from the middle line?
68 (34.1% on both sides of the line)
how far apart a centile lines spaced on a growth chart
2 or 3
what do you need to tell whether a child is growing normally
several plots on a growth chart (shows if normal progression- can be within normal ranges but not growing at normal rate)
how does height velocity change between the phases of growth
very fast in infant stage (nutrition led), slows in
child stage (growth hormone led)
increases again in pubertal stage (sex steroid led)
what can being overweight can in development
precocious puberty
what is normal growth
child whose measurements and rate of growth are within the normal range compared with children of their age
what has happened to growth charts in recent years
shift to the right- increases in weight (severe obesity may be distorting charts),
height also increasing
how should babies be weighed
without clothes or nappy
how should you measure head circumference
where head circumference is widest- take 3 and average, don’t go over ears
when should you measure length
only before 2 years if concerned - will vary a lot because of e.g. mood
when should you start measuring height
from 2 years
how should you measure height
no shoes, on expiration, don’t try and stretch up
how do you plot a growth chart
record measurement, date in ink, plot in pencil, don’t join dots, (age in weeks for first 6-12 months)
what does a child on the x centile mean
childs measurements are exactly on the centile line or within a 1/4 of a space
if they are not this then said to be between x and y centile
when should growth charts be concerning
if progression crosses two centiles, or if out of normal ranges
what is the average age of onset of puberty
girls 11 years
boys 6 years
what are the gonadotrophins
FSH and LH
what causes the onset of puberty
when the secretion of gonadotrophin releasing hormone (GnRH) by the hypothalamus, which is largely but not entirely suppressed during childhood, increases so that pulsatile secretion of luteinizing hormone (LH) increases, resulting in sufficient sex steroid production to result in the secondary sexual development
what does LH cause in boys
stimulates the Leydig cells to produce testosterone which induces the features of secondary sexual development
what does FSH do in boys
binds to receptors on the Sertoli cells, enhancing spermatogenesis.
