The function j_index produces J-Index values a tibble object.
Value
If a data.frame object is passed, then a tibble object with two columns: subject id and corresponding J-Index value is returned. If a vector of glucose values is passed, then a tibble object with just the J-Index value is returned. as.numeric() can be wrapped around the latter to output just a numeric value.
Details
A tibble object with 1 row for each subject, a column for subject id and a column for J-Index values is returned. NA glucose values are omitted from the calculation of the J-Index.
J-Index score is calculated by \(.001 * [mean(G) + sd(G)]^2\) where G is the list of Glucose Measurements.
References
Wojcicki (1995) "J"-index. A new proposition of the assessment of current glucose control in diabetic patients Hormone and Metabolic Research 27 .41-42, doi:10.1055/s-2007-979906 .
Examples
data(example_data_1_subject)
j_index(example_data_1_subject)
#> # A tibble: 1 × 2
#> id J_index
#> <fct> <dbl>
#> 1 Subject 1 24.6
data(example_data_5_subject)
j_index(example_data_5_subject)
#> # A tibble: 5 × 2
#> id J_index
#> <fct> <dbl>
#> 1 Subject 1 24.6
#> 2 Subject 2 73.3
#> 3 Subject 3 39.5
#> 4 Subject 4 25.2
#> 5 Subject 5 54.4