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Rcpp MODD Calculation

Source: R/cgmguru-functions-docs.R
modd_rcpp.Rd

Calculates Mean of Daily Differences (MODD) with an Rcpp backend. The preprocessing follows the iglu day-grid approach used by iglu::modd: CGM data are linearly interpolated to a regular midnight-aligned full-day grid, respecting inter_gap, before same-time-of-day differences are calculated.

Usage

modd_rcpp(data, lag = 1, tz = "", inter_gap = 45)

Arguments

data

A dataframe containing CGM data with columns:

  • id: Subject identifier

  • time: POSIXct measurement timestamp

  • gl: Glucose value in mg/dL

lag

Whole number of days separating paired same-time-of-day glucose observations. Defaults to 1.

tz

Time zone used for day-grid alignment when supplied.

inter_gap

Maximum gap, in minutes, over which linear interpolation is allowed. Defaults to 45, matching iglu's internal default.

Value

A tibble with columns id and MODD.

References

Service, F. John, and Roger L. Nelson. "Characteristics of glycemic stability." Diabetes Care 3.1 (1980): 58-62.

See also

iglu::modd, conga_rcpp, mage_rcpp

Examples

library(iglu)
data(example_data_5_subject)
modd_rcpp(example_data_5_subject)
#> # A tibble: 5 × 2
#>   id         MODD
#>   <chr>     <dbl>
#> 1 Subject 1  27.8
#> 2 Subject 2  44.1
#> 3 Subject 3  48.2
#> 4 Subject 4  24.9
#> 5 Subject 5  59.4
modd_rcpp(example_data_5_subject, lag = 2)
#> # A tibble: 5 × 2
#>   id         MODD
#>   <chr>     <dbl>
#> 1 Subject 1  27.7
#> 2 Subject 2  46.0
#> 3 Subject 3  47.1
#> 4 Subject 4  24.9
#> 5 Subject 5  56.0