Chapter 3 Growth charts in JAMES

3.1 Chart naming conventions

The link https://groeidiagrammen.nl/ocpu/lib/james/www/ contains an interactive overview of the available growth charts. There are many different charts: for boys and girls, for preterms, for different age ranges, for specific ethnic groups, for height, weight, BMI, and so on. Each chart has a chart code, a character code identifying the design. This section explains the construction of the chart codes.

The GitHub repository https://github.com/growthcharts/chartbox contains the chart libraries that are available to JAMES. The list_charts() function produces a tabular overview.

charts <- chartbox::list_charts()
dim(charts)

## [1] 478   8

charts[c(1, 22, 23, 300, 301, 340), ]

##     chartgrp chartcode population    sex design  side language week
## 1     nl2010      DJAA         DS   male      A front    dutch     
## 22    nl2010      DMBA         DS female      B front    dutch     
## 23    nl2010      DMBB         DS female      B  back    dutch     
## 300  preterm   PMAAN32         PT female      A front    dutch   32
## 301  preterm   PMAAN33         PT female      A front    dutch   33
## 340  preterm   PMAHN36         PT female      A   hgt    dutch   36

The chartbox package currently contains three chart groups: nl2010, preterm and who. Each group collects charts of a similar type.

Chart Group	N	Chart code	Description	Source
`nl2010`	140	CCCC	Dutch children 0-21 years, including minorities	Talma et al. (2010)
`preterm`	240	CCCCCNN	Dutch preterms, ga <= 36 weeks, 0-4 years	Bocca-Tjeertes et al. (2012)
`who`	14	CCCC	WHO Child Growth Standards 0-4 years	WHO

The chart code is an alpha-numeric code of four (for nl2010 and who) or seven (for preterm) that uniquely identifies each of the charts. The table below specifies the full coding schema used to construct the chart codes.

Position	Field	Value	Description
1	Population	N	Dutch
		T	Turkish
		M	Moroccan
		H	Hindostan
		P	Preterm
		W	WHO
2	Sex	J	Male
		M	Female
3	Design	A	0-15 months
		B	0-4 years, WFH
		C	1-21 years
		D	0-21 years
		E	0-4 years, WFA
4	Side	A	A4, front
		B	A4, back
		C	A4, back, no `hdc`
		D	square, `dsc`
		H	square, `hgt`
		O	square, `hdc`
		Q	square, `bmi`
		R	square, `wfh`
		W	square, `wgt`
		X	A4, double sided
5	Language	N	Dutch
		E	English
6-7	Week	25-36	Gestational age

For illustration, code NJAA references to Dutch (N), boys (J), 0-15 month (A), front side (A). Likewise, PMEAN33 codes for the chart of preterm (M), girls (M), 0-4 years (E), front side (A), Dutch language (N) born at 33 weeks of gestation (33).

Some forms hold multiple growth charts. For example, the NJAA chart is designed for A4 paper size (297mm \(\times\) 210mm) and contains three growth charts: head circumference by age, length by age, and weight by age. Some others have no diagram, like NJAB. All square formats hold just one growth chart. All of the square forms have equal sizes (160mm \(\times\) 160mm).

The following table lists the measures per design-form combination.

Design	Side	Measure	Description
A	A	`hdc`	Head circumference by age, 0-15 mo
		`hgt`	Length by age, 0-15 mo
		`wgt`	Weight by age, 0-15 mo
	B		Backside explanations
	D	`dsc`	D-score by age, 0-15 mo
	H	`hgt`	Length by age, 0-15 mo
	O	`hdc`	Head circumference by age, 0-15 mo
	W	`wgt`	Weight by age, 0-15 mo
B	A	`wfh`	Weight for height, 0-4 yr
		`hgt`	Length by age, 0-4 yr
	B	`hdc`	Head circumference by age, 0-4 yr
	C		Backside explanations
	D	`dsc`	D-score by age, 0-4 yr
	H	`hgt`	Height by age, 0-4 yr
	O	`hdc`	Head circumference by age, 0-4 yr
	R	`wfh`	Weight for height, 0-4 yr
	W	`wgt`	Weight by age, 0-4 yr
C	A	`wfh`	Weight for height, 1-21 yr
		`hgt`	height by age, 1-21 yr
	B	`bmi`	BMI by age, 1-21 yr
		`hdc`	Head circumference by age, 1-21 yr
	C	`bmi`	BMI by age, 1-21 yr
	H	`hgt`	Height by age, 1-21 yr
	O	`hdc`	Head circumference by age, 1-21 yr
	Q	`bmi`	Body mass index by age, 1-21 yr
	R	`wfh`	Weight for height, 1-21 yr
E	A	`wgt`	Weight by age, 0-4 yr
		`hgt`	height by age, 0-4 yr
	B	`hdc`	Head circumference by age, 0-4 yr
	H	`hgt`	Height by age, 0-4 yr
	O	`hdc`	Head circumference by age, 0-4 yr
	W	`wgt`	Weight by age, 0-4 yr

References

Bocca-Tjeertes, I. F. A., S. van Buuren, A. F. Bos, J. M. Kerstens, E. M. ten Vergert, and Reijneveld.S. A. 2012. “Growth of Preterm and Fullterm Children Aged 0-4 Years: Integrating Median Growth and Variability in Growth Charts.” Journal of Pediatrics 161 (3): 460–65.

Talma, H., Y. Schonbeck, B. Bakker, R. A. Hirasing, and S. van Buuren. 2010. Groeidiagrammen 2010: Handleiding Bij Het Meten En Wegen van Kinderen En Het Invullen van Groeidiagrammen. Leiden: TNO Kwaliteit van Leven.