#' @section Deprecated function names: Future versions of \pkg{icd} will drop
#'   the \code{icd_} prefix. For example, \code{charlson} should be used in
#'   favor of \code{icd_charlson}. To distinguish \pkg{icd} function calls,
#'   consider using the prefix \code{icd::} instead, e.g., \code{icd::charlson}.
#'   Functions which specifically operate on either ICD-9 or ICD-10 codes or
#'   their sub-types will retain the prefix. E.g.
#'   \code{\link{icd9_comorbid_ahrq}}. \pkg{icd} specific classes also retain
#'   the prefix, e.g., \code{\link{icd_wide_data}}.

