| Title: | Evidence-Based Assessment Tools for Diagnostic Test Evaluation |
| Version: | 0.1.0 |
| Description: | Provides functions for evidence-based assessment of diagnostic tests. Includes calculation of common diagnostic accuracy statistics, Bayesian updating of probabilities, interpretation of likelihood ratios, and visualization using a Fagan nomogram. |
| License: | MIT + file LICENSE |
| Encoding: | UTF-8 |
| RoxygenNote: | 8.0.0 |
| URL: | https://github.com/rmcgill777/ebaTools |
| BugReports: | https://github.com/rmcgill777/ebaTools/issues |
| NeedsCompilation: | no |
| Packaged: | 2026-07-19 17:06:19 UTC; rmcgill777 |
| Author: | Ryan McGill [aut, cre] |
| Maintainer: | Ryan McGill <rmcgill@wm.edu> |
| Repository: | CRAN |
| Date/Publication: | 2026-07-28 16:40:16 UTC |
Bayesian Updating
Description
Calculate post-test probabilities from a pre-test probability and positive/negative likelihood ratios.
Usage
bayes_update(pretest_probability, lr_positive, lr_negative)
Arguments
pretest_probability |
Numeric value between 0 and 1 representing the pre-test probability. |
lr_positive |
Positive likelihood ratio. |
lr_negative |
Negative likelihood ratio. |
Value
An object of class "bayes_update" containing:
- pretest_probability
Original pre-test probability.
- post_positive
Post-test probability following a positive test.
- post_negative
Post-test probability following a negative test.
Evidence-Based Assessment Interpretation
Description
Interpret a post-test probability using evidence-based assessment decision thresholds.
Usage
eba_interpretation(
post_probability,
wait_threshold = 0.1,
treat_threshold = 0.7
)
Arguments
post_probability |
Numeric value between 0 and 1. |
wait_threshold |
Threshold below which the condition is considered unlikely. Default = 0.10. |
treat_threshold |
Threshold above which the condition is considered likely. Default = 0.70. |
Value
An object of class "eba_interpretation".
Evidence-Based Assessment Statistics
Description
Calculate evidence-based assessment statistics from a 2 × 2 contingency table.
Usage
eba_stats(tp, fp, fn, tn)
Arguments
tp |
Number of true positives. |
fp |
Number of false positives. |
fn |
Number of false negatives. |
tn |
Number of true negatives. |
Value
An object of class "eba_stats".
Examples
eba_stats(
tp = 50,
fp = 10,
fn = 5,
tn = 100
)
Fagan Nomogram
Description
Plot pre-test and post-test probabilities using likelihood ratios.
Usage
fagan_nomogram(pretest_probability, lr_positive, lr_negative)
Arguments
pretest_probability |
Numeric value between 0 and 1. |
lr_positive |
Positive likelihood ratio. |
lr_negative |
Negative likelihood ratio. |
Value
Invisibly returns the calculated probabilities.