Description Usage Arguments Value Examples

This function creates a roc stat object which can be passed as input
to the `set_stats()`

function when building an aba model. This stat performs
a traditional ROC / cutpoint analysis from a binary outcome using the
`optimal.cutpoints`

function from the `OptimalCutpoints`

package. Note that
outcomes for this model should be binary and coded as 0 = healthy and
1 = disease.
Coefficients will be presented as the optimal cutpoint for the model derived
from Youden's index (or whatever method is specified).
Default metrics include AUC.

1 2 3 4 5 6 | ```
stat_roc(
direction = "<",
method = "Youden",
std.beta = FALSE,
complete.cases = TRUE
)
``` |

`direction` |
'<' or '>. Which direction to interpret as being further from the healthy value. '<' is the default value and is interpreted as increasing predictor values are worse. '>' is therefore interpreted as higher predictor values are closer to healthy (outcome value of 0). |

`method` |
string. Which method to use to calculate the optimal cutoff
value. See the |

`std.beta` |
logical. Whether to standardize model predictors and covariates prior to analysis. |

`complete.cases` |
logical. Whether to only include the subset of data with no missing data for any of the outcomes, predictors, or covariates. Note that complete cases are considering within each group - outcome combination but across all predictor sets. |

An abaStat object with `glm`

stat type.

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 | ```
data <- adnimerge %>% dplyr::filter(VISCODE == 'bl')
# fit a roc model to predict a binary outcome
model <- data %>% aba_model() %>%
set_groups(
everyone(),
DX_bl %in% c('MCI', 'AD')
) %>%
set_outcomes(CSF_ABETA_STATUS_bl) %>%
set_predictors(PLASMA_PTAU181_bl, PLASMA_NFL_bl) %>%
set_stats(
stat_roc(method='Youden')
) %>%
fit()
# summarise model
model_summary <- model %>% summary()
# if using predictors where higher values are better, then flip direction
model2 <- model %>%
set_predictors(PLASMA_ABETA_bl) %>%
set_stats(
stat_roc(direction = '>')
) %>%
fit()
model2_summary <- model2 %>% aba_summary()
``` |

Embedding an R snippet on your website

Add the following code to your website.

For more information on customizing the embed code, read Embedding Snippets.