A data frame containing the age-dependent distribution of the D-score for children aged 0-5 years. The distribution is modelled after the LMS distribution (Cole & Green, 1992), and is equal for both boys and girls. The LMS values can be used to graph reference charts and to calculate age-conditonal Z-scores, also known as DAZ.

builtin_references

Format

A data.frame with 265 rows and 17 variables:

NameLabel
popPopulation, either "dutch" or "gcdg"
ageDecimal age in years
muM-curve, median D-score, P50
sigmaS-curve, spread expressed as coefficient of variation
nuL-curve, the lambda coefficient of the LMS model for skewness
P3P3 percentile
P10P10 percentile
P25P25 percentile
P50P50 percentile
P75P75 percentile
P90P90 percentile
P97P97 percentile
SDM2-2SD centile
SDM1-1SD centile
SD00SD centile, median
SDP1+1SD centile
SDP2+2SD centile

Details

The "dutch" references were calculated from the SMOCC data, and cover age range 0-2.5 years (van Buuren, 2014). The "gcdg" references were calculated from the 15 cohorts of the GCDG-study, and cover age range 0-5 years (Weber, 2019).

References

Cole TJ, Green PJ (1992). Smoothing reference centile curves: The LMS method and penalized likelihood. Statistics in Medicine, 11(10), 1305-1319.

Van Buuren S (2014). Growth charts of human development. Stat Methods Med Res, 23(4), 346-368. https://stefvanbuuren.name/publication/van-buuren-2014-gc/

Weber AM, Rubio-Codina M, Walker SP, van Buuren S, Eekhout I, Grantham-McGregor S, Caridad Araujo M, Chang SM, Fernald LCH, Hamadani JD, Hanlon A, Karam SM, Lozoff B, Ratsifandrihamanana L, Richter L, Black MM (2019). The D-score: a metric for interpreting the early development of infants and toddlers across global settings. BMJ Global Health, BMJ Global Health 4: e001724. https://gh.bmj.com/content/bmjgh/4/6/e001724.full.pdf

See also

Examples

head(builtin_references)
#> pop age mu sigma nu P3 P10 P25 P50 P75 P90 P97 #> 1 dutch 0.0383 8.81 0.3126 1.3917 3.15 5.07 6.91 8.81 10.57 12.07 13.49 #> 2 dutch 0.0575 10.59 0.2801 1.4418 4.32 6.49 8.52 10.59 12.50 14.12 15.64 #> 3 dutch 0.0767 12.27 0.2526 1.4891 5.61 7.96 10.10 12.27 14.28 15.97 17.56 #> 4 dutch 0.0958 13.87 0.2291 1.5331 6.99 9.43 11.64 13.87 15.93 17.67 19.30 #> 5 dutch 0.1150 15.39 0.2089 1.5722 8.42 10.89 13.13 15.39 17.47 19.23 20.89 #> 6 dutch 0.1342 16.83 0.1916 1.6049 9.86 12.32 14.56 16.83 18.92 20.69 22.36 #> SDM2 SDM1 SD0 SDP1 SDP2 #> 1 2.78 5.94 8.81 11.39 13.76 #> 2 3.88 7.46 10.59 13.38 15.94 #> 3 5.12 8.98 12.27 15.20 17.87 #> 4 6.47 10.48 13.87 16.87 19.61 #> 5 7.89 11.95 15.39 18.43 21.21 #> 6 9.33 13.39 16.83 19.88 22.68