. The weights of longitudinal and transverse samples are combined without any adjustment and fitted.
A single model generates a series of continuous curves, forming a specific age weight standard for each sex. Zaiquasi
Before modeling the curve, the same exponential conversion operation is used for the ages of boys and girls. both sexes
The weight data is skewed, so when expressing the model, except the median and approximate coefficient of variation, it is skewed.
Relevant parameters are also fitted. When fitting skewness, the girl curve needs more freedom for this parameter.
The numbers fit the curve.
height
/
Height and weight
. Set length
(45
Until/very
1 10
centimetre
)
Weight and height difference
(65
Until/very
120
centimetre
)
Weight scale
Similar specific age length
/
The procedure used in the height standard is to install a single module.
In the formula, the value of section height is increased.
0.7
Cm, when the model is fitted,
65.7
Until/very
120.7
Cm length
The percentile curve of body length and weight in the length interval recedes.
0.7
Cm, so as to get
65
Until/very
120
Plum, unit of length/weight/area
A specific height weight standard corresponding to the meter height range. Lower limit of body length and weight standard
(45
centimetre
)
Refers to the birth of a girl.
The average length of time and body is low.
2
Standard deviation. The upper limit of the height and weight standard should apply to
60
The highest last month.
Kids, so
120
The ratio of centimeters to fingers
60
The average height of boys is about 6 months higher than that of boys.
2
Standard deviation. Length and weight
The overlap between the upper limit of the standard and the lower limit of the height and weight standard is to facilitate the application of these standards to nutrition.
Serious shortage of people and acute malnutrition in emergencies.
There is no evidence that the length is set.
/
Height and weight standards need to be adjusted according to body length.
/
The height is similar to the above years.
Changes in age. When fitting the median and variance curves, follow the procedures of the first two standards mentioned above. The length of the girl
/
body
The results of the final model with high specific gravity show that it is necessary to see whether the curve can be changed by fitting kurtosis.
Enter. However, the adjustment of kurtosis has little effect on the final percentile. Therefore, considering the fitting
The fourth parameter may make the application of the standard more complicated and lead to the inconsistency between the two sexes, thus leading to the final song.
There is no adjustment of kurtosis when drawing lines. The degree of freedom of median and variance curves is different between boys and girls.
height
/
Height and body mass index (BMI) combines two measurement methods of overlapping age groups.
(
Weight and length
/
height
)
Different growth rates, which may explain why the WHO is the ultimate standard.
(
Including boys and girls.
)
Like other reference standards, the curve is slightly distorted.
Age-specific body mass index
. Body mass index is weight.
(
kilogram
)
Having a horizontal length or an upright height.
(
rice
)
The ratio of squares.
In order to deal with the difference between body length and height, the method used to formulate the age-specific body mass index standard is the same as that mentioned above for many years.
Age and length
/
The method of height is different. Since the ratio of body mass index is based on the square of body length or height,
So it is impossible to increase the height value.
0.7
Cm, and then perform regression transformation on them after fitting. because
This is the foundation of the solution.
24
Two groups with overlapping age data of less than 6 months and above were formulated separately.
Standards for young and old children. When formulating age-specific body mass index standards based on body length
(0
reach
2
year
)
When you first increase the height value.
0.7
Cm, and then cluster the body length data of longitudinal clustering samples with the cross section.
Height data of the sample
( 18
reach
30
one month
)
Combine them. Similarly, in formulating
2
reach
five
18 years old, from
Subtract from the length value
0.7
Cm, and then compare the height of the horizontal cluster sample with the length of the vertical cluster sample.
according to
( 18
reach
24
one month
)
Combine them. In this way, by
18
reach
30
Last month's same set of data has been generated for a long time.
Body mass index standards for infants and older children. The final separation between the two standards essentially reflects the length.
Different from height.
0.7
Centimeter. However, this does not mean that children of a certain age will have a stage.
Age-specific body mass index based on length and height
z
Value, because considering the nature of body mass index ratio,
Mathematically speaking, this is impossible.
Before drawing the body mass index curve by age based on body length, other age-based standards need to be constructed.
At the same time, the age index is converted. But you don't have to enter the age-specific body mass index based on height.
Do this transformation. Who's age-specific body mass index standards based on length and height do not overlap, that is, based on
The interval of body length is in the first one
730
Height-based intervals begin on the first day.
73 1
The day began. continue
cubic
Spline (
Cubic spline function
)
When fitting, the length and height are the standards.
The standard uses different degrees of freedom parameters.
Number; Similarly, the freedom parameters of the final curve of boys and girls are different.