prec_lr (prec_pos_lr, prec_neg_lr) to simplify positive/negative LRsprec_lraddition of function for Cohen’s kappa
update shiny app to include kappa
POSSIBLE BREAKING CHANGE: arguments in prec_rateratio renamed from *_exp and *_control to *1 and *2 for consistency with other functions
prec_sens and prec_spec allow prev and conf.width
multiple notes allowed in print method
add contributing guidelines
prec_sens_spec removed. Confidence intervals and sample sizes are quite different to other methods. A two step approach using prec_sens and prec_spec is instead recommended
addition of various tests
addition of rate ratio method