Provides additional information on percentiles of D-score and age in months for the percentiles 2, 10, 50, 90 and 98. User either provides known van Wiechen milestones, or information to calculate the recommended van Wiechen milestones based on age and past milestones.

Usage

percentiles_vwc(
  txt = "",
  p = 90,
  n = 6,
  vwc = NULL,
  session = "",
  format = "1.0",
  loc = "",
  ...
)

Arguments

txt: A JSON string, URL, or file with BDS data in JSON format. Data should conform to the BDS JGZ 3.2.5 specification.
p: Reference percentile indicating the expected probability of a positive van Wiechen outcome given child age. Higher values correspond with easier items.
n: Number of van Wiechen items to suggest. By default returns all items within set probability limits.
vwc: Vector of string values matching van Wiechen milestones. Bypasses calculations and directly supply the milestones of interest
session: Optional session key if data is already uploaded to sitehost.
format: JSON schema version, e.g., "3.0". Used when uploading.
loc: Deprecated. Use session instead.
...: Ignored

Value

A table.

Author

Arjan Huizing 2025

Examples

fn <- system.file("testdata", "Laura_S.json", package = "james")
percentiles_vwc(txt = fn, p = 50, n = 3)
#> # A tibble: 3 × 11
#>   item         D2   D10   D50   D90   D98    A2   A10   A50   A90   A98
#>   <chr>     <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl> <dbl>
#> 1 ddifmd027  60.8  64.4  69    73.6  77.2  20.9  24.7  30.5    NA    NA
#> 2 ddigmm073  58.9  62.5  67.1  71.7  75.3  19.1  22.6  28.0    NA    NA
#> 3 ddicmm050  61.3  64.9  69.5  74.1  77.7  21.4  25.2  31.2    NA    NA