# ==================================================================== # # TITLE # # Antimicrobial Resistance (AMR) Analysis # # # # AUTHORS # # Berends MS (m.s.berends@umcg.nl), Luz CF (c.f.luz@umcg.nl) # # # # LICENCE # # This program is free software; you can redistribute it and/or modify # # it under the terms of the GNU General Public License version 2.0, # # as published by the Free Software Foundation. # # # # This program is distributed in the hope that it will be useful, # # but WITHOUT ANY WARRANTY; without even the implied warranty of # # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the # # GNU General Public License for more details. # # ==================================================================== # #' Resistance of isolates #' #' This functions can be used to calculate the (co-)resistance of isolates (i.e. percentage S, SI, I, IR or R [of a vector] of isolates). The functions \code{rsi} and \code{n_rsi} can be used in \code{dplyr}s \code{\link[dplyr]{summarise}} and support grouped variables, see \emph{Examples}. #' @param tbl \code{data.frame} containing columns with antibiotic interpretations. #' @param ab character vector with 1, 2 or 3 antibiotics that occur as column names in \code{tbl}, like \code{ab = c("amox", "amcl")} #' @param ab1,ab2 vector of antibiotic interpretations, they will be transformed internally with \code{\link{as.rsi}} #' @param interpretation antimicrobial interpretation of which the portion must be calculated. Valid values are \code{"S"}, \code{"SI"}, \code{"I"}, \code{"IR"} or \code{"R"}. #' @param minimum minimal amount of available isolates. Any number lower than \code{minimum} will return \code{NA} with a warning (when \code{warning = TRUE}). #' @param as_percent return output as percent (text), will else (at default) be a double #' @param info calculate the amount of available isolates and print it, like \code{n = 423} #' @param warning show a warning when the available amount of isolates is below \code{minimum} #' @details Remember that you should filter your table to let it contain \strong{only first isolates}! #' \if{html}{ #' \cr \cr #' To calculate the probability (\emph{p}) of susceptibility of one antibiotic, we use this formula: #' \out{
}\figure{mono_therapy.png}\out{
} #' To calculate the probability (\emph{p}) of susceptibility of more antibiotics (i.e. combination therapy), we need to check whether one of them has a susceptible result (as numerator) and count all cases where all antibiotics were tested (as denominator). \cr #' For two antibiotics: #' \out{
}\figure{combi_therapy_2.png}\out{
} #' \cr #' For three antibiotics: #' \out{
}\figure{combi_therapy_3.png}\out{
} #' } #' @keywords rsi antibiotics isolate isolates #' @return Double or, when \code{as_percent = TRUE}, a character. #' @rdname rsi #' @export #' @importFrom dplyr %>% n_distinct filter filter_at pull vars all_vars any_vars #' @examples #' library(dplyr) #' #' septic_patients %>% #' group_by(hospital_id) %>% #' summarise(cipro_susceptibility = rsi(cipr, interpretation = "S"), #' n = n_rsi(cipr)) # n_rsi works like n_distinct in dplyr #' #' septic_patients %>% #' group_by(hospital_id) %>% #' summarise(cipro_S = rsi(cipr, interpretation = "S", #' as_percent = TRUE, warning = FALSE), #' cipro_n = n_rsi(cipr), #' genta_S = rsi(gent, interpretation = "S", #' as_percent = TRUE, warning = FALSE), #' genta_n = n_rsi(gent), #' combination_S = rsi(cipr, gent, interpretation = "S", #' as_percent = TRUE, warning = FALSE), #' combination_n = n_rsi(cipr, gent)) #' #' # calculate resistance #' rsi(septic_patients$amox) #' # or susceptibility #' rsi(septic_patients$amox, interpretation = "S") #' #' # calculate co-resistance between amoxicillin/clav acid and gentamicin, #' # so we can review that combination therapy does a lot more than mono therapy: #' septic_patients %>% rsi_df(ab = "amcl", interpretation = "S") # = 67.8% #' septic_patients %>% rsi_df(ab = "gent", interpretation = "S") # = 69.1% #' septic_patients %>% rsi_df(ab = c("amcl", "gent"), interpretation = "S") # = 90.6% #' #' \dontrun{ #' # calculate current empiric combination therapy of Helicobacter gastritis: #' my_table %>% #' filter(first_isolate == TRUE, #' genus == "Helicobacter") %>% #' rsi_df(ab = c("amox", "metr")) # amoxicillin with metronidazole #' } rsi <- function(ab1, ab2 = NA, interpretation = 'IR', minimum = 30, as_percent = FALSE, info = FALSE, warning = TRUE) { ab1.name <- deparse(substitute(ab1)) if (ab1.name %like% '.[$].') { ab1.name <- unlist(strsplit(ab1.name, "$", fixed = TRUE)) ab1.name <- ab1.name[length(ab1.name)] } if (!ab1.name %like% '^[a-z]{3,4}$') { ab1.name <- 'rsi1' } if (length(ab1) == 1 & is.character(ab1)) { stop('`ab1` must be a vector of antibiotic interpretations.', '\n Try rsi(', ab1, ', ...) instead of rsi("', ab1, '", ...)', call. = FALSE) } ab2.name <- deparse(substitute(ab2)) if (ab2.name %like% '.[$].') { ab2.name <- unlist(strsplit(ab2.name, "$", fixed = TRUE)) ab2.name <- ab2.name[length(ab2.name)] } if (!ab2.name %like% '^[a-z]{3,4}$') { ab2.name <- 'rsi2' } if (length(ab2) == 1 & is.character(ab2)) { stop('`ab2` must be a vector of antibiotic interpretations.', '\n Try rsi(', ab2, ', ...) instead of rsi("', ab2, '", ...)', call. = FALSE) } interpretation <- paste(interpretation, collapse = "") ab1 <- as.rsi(ab1) ab2 <- as.rsi(ab2) tbl <- tibble(rsi1 = ab1, rsi2 = ab2) colnames(tbl) <- c(ab1.name, ab2.name) if (length(ab2) == 1) { r <- rsi_df(tbl = tbl, ab = ab1.name, interpretation = interpretation, minimum = minimum, as_percent = FALSE, info = info, warning = warning) } else { if (length(ab1) != length(ab2)) { stop('`ab1` (n = ', length(ab1), ') and `ab2` (n = ', length(ab2), ') must be of same length.', call. = FALSE) } if (!interpretation %in% c('S', 'IS', 'SI')) { warning('`interpretation` not set to S or I/S, albeit analysing a combination therapy.', call. = FALSE) } r <- rsi_df(tbl = tbl, ab = c(ab1.name, ab2.name), interpretation = interpretation, minimum = minimum, as_percent = FALSE, info = info, warning = warning) } if (as_percent == TRUE) { percent(r, force_zero = TRUE) } else { r } } #' @export #' @rdname rsi rsi_df <- function(tbl, ab, interpretation = 'IR', minimum = 30, as_percent = FALSE, info = TRUE, warning = TRUE) { # in case tbl$interpretation already exists: interpretations_to_check <- paste(interpretation, collapse = "") # validate: if (min(grepl('^[a-z]{3,4}$', ab)) == 0 & min(grepl('^rsi[1-2]$', ab)) == 0) { for (i in 1:length(ab)) { ab[i] <- paste0('rsi', i) } } if (!grepl('^(S|SI|IS|I|IR|RI|R){1}$', interpretations_to_check)) { stop('Invalid `interpretation`; must be "S", "SI", "I", "IR", or "R".') } if ('is_ic' %in% colnames(tbl)) { if (n_distinct(tbl$is_ic) > 1 & warning == TRUE) { warning('Dataset contains isolates from the Intensive Care. Exclude them from proper epidemiological analysis.') } } # transform when checking for different results if (interpretations_to_check %in% c('SI', 'IS')) { for (i in 1:length(ab)) { lijst <- tbl[, ab[i]] if ('I' %in% lijst) { tbl[which(tbl[ab[i]] == 'I'), ][ab[i]] <- 'S' } } interpretations_to_check <- 'S' } if (interpretations_to_check %in% c('RI', 'IR')) { for (i in 1:length(ab)) { lijst <- tbl[, ab[i]] if ('I' %in% lijst) { tbl[which(tbl[ab[i]] == 'I'), ][ab[i]] <- 'R' } } interpretations_to_check <- 'R' } # get fraction if (length(ab) == 1) { numerator <- tbl %>% filter(pull(., ab[1]) == interpretations_to_check) %>% nrow() denominator <- tbl %>% filter(pull(., ab[1]) %in% c("S", "I", "R")) %>% nrow() } else if (length(ab) == 2) { if (interpretations_to_check != 'S') { warning('`interpretation` not set to S or I/S, albeit analysing a combination therapy.', call. = FALSE) } numerator <- tbl %>% filter_at(vars(ab[1], ab[2]), any_vars(. == interpretations_to_check)) %>% filter_at(vars(ab[1], ab[2]), all_vars(. %in% c("S", "R", "I"))) %>% nrow() denominator <- tbl %>% filter_at(vars(ab[1], ab[2]), all_vars(. %in% c("S", "R", "I"))) %>% nrow() } else if (length(ab) == 3) { if (interpretations_to_check != 'S') { warning('`interpretation` not set to S or I/S, albeit analysing a combination therapy.', call. = FALSE) } numerator <- tbl %>% filter_at(vars(ab[1], ab[2], ab[3]), any_vars(. == interpretations_to_check)) %>% filter_at(vars(ab[1], ab[2], ab[3]), all_vars(. %in% c("S", "R", "I"))) %>% nrow() denominator <- tbl %>% filter_at(vars(ab[1], ab[2], ab[3]), all_vars(. %in% c("S", "R", "I"))) %>% nrow() } else { stop('Maximum of 3 drugs allowed.') } # build text part if (info == TRUE) { cat('n =', denominator) info.txt1 <- percent(denominator / nrow(tbl)) if (denominator == 0) { info.txt1 <- 'none' } info.txt2 <- gsub(',', ' and', ab %>% abname(tolower = TRUE) %>% toString(), fixed = TRUE) info.txt2 <- gsub('rsi1 and rsi2', 'these two drugs', info.txt2, fixed = TRUE) info.txt2 <- gsub('rsi1', 'this drug', info.txt2, fixed = TRUE) cat(paste0(' (of ', nrow(tbl), ' in total; ', info.txt1, ' tested on ', info.txt2, ')\n')) } # calculate and format y <- numerator / denominator if (as_percent == TRUE) { y <- percent(y, force_zero = TRUE) } if (denominator < minimum) { if (warning == TRUE) { warning(paste0('TOO FEW ISOLATES OF ', toString(ab), ' (n = ', denominator, ', n < ', minimum, '); NO RESULT.')) } y <- NA } # output y } #' @export #' @rdname rsi n_rsi <- function(ab1, ab2 = NA) { if (length(ab1) == 1 & is.character(ab1)) { stop('`ab1` must be a vector of antibiotic interpretations.', '\n Try n_rsi(', ab1, ', ...) instead of n_rsi("', ab1, '", ...)', call. = FALSE) } ab1 <- as.rsi(ab1) if (length(ab2) == 1 & all(is.na(ab2))) { # only 1 antibiotic length(ab1[!is.na(ab1)]) } else { if (length(ab2) == 1 & is.character(ab2)) { stop('`ab2` must be a vector of antibiotic interpretations.', '\n Try n_rsi(', ab2, ', ...) instead of n_rsi("', ab2, '", ...)', call. = FALSE) } ab2 <- as.rsi(ab2) tbl <- tibble(ab1, ab2) tbl %>% filter(!is.na(ab1) & !is.na(ab2)) %>% nrow() } } #' Predict antimicrobial resistance #' #' Create a prediction model to predict antimicrobial resistance for the next years on statistical solid ground. Standard errors (SE) will be returned as columns \code{se_min} and \code{se_max}. See Examples for a real live example. #' @param tbl table that contains columns \code{col_ab} and \code{col_date} #' @param col_ab column name of \code{tbl} with antimicrobial interpretations (\code{R}, \code{I} and \code{S}), supports tidyverse-like quotation #' @param col_date column name of the date, will be used to calculate years if this column doesn't consist of years already, supports tidyverse-like quotation #' @param year_max highest year to use in the prediction model, deafults to 15 years after today #' @param year_every unit of sequence between lowest year found in the data and \code{year_max} #' @param model the statistical model of choice. Valid values are \code{"binomial"} (or \code{"binom"} or \code{"logit"}) or \code{"loglin"} or \code{"linear"} (or \code{"lin"}). #' @param I_as_R treat \code{I} as \code{R} #' @param preserve_measurements overwrite predictions of years that are actually available in the data, with the original data. The standard errors of those years will be \code{NA}. #' @param info print textual analysis with the name and \code{\link{summary}} of the model. #' @return \code{data.frame} with columns \code{year}, \code{probR}, \code{se_min} and \code{se_max}. #' @seealso \code{\link{lm}} \cr \code{\link{glm}} #' @export #' @importFrom dplyr %>% pull mutate group_by_at summarise filter #' @importFrom reshape2 dcast #' @examples #' \dontrun{ #' # use it directly: #' rsi_predict(tbl = tbl[which(first_isolate == TRUE & genus == "Haemophilus"),], #' col_ab = "amcl", col_date = "date") #' #' # or with dplyr so you can actually read it: #' library(dplyr) #' tbl %>% #' filter(first_isolate == TRUE, #' genus == "Haemophilus") %>% #' rsi_predict(amcl, date) #' } #' #' #' # real live example: #' library(dplyr) #' septic_patients %>% #' # get bacteria properties like genus and species #' left_join_microorganisms("bactid") %>% #' # calculate first isolates #' mutate(first_isolate = #' first_isolate(., #' "date", #' "patient_id", #' "bactid", #' col_specimen = NA, #' col_icu = NA)) %>% #' # filter on first E. coli isolates #' filter(genus == "Escherichia", #' species == "coli", #' first_isolate == TRUE) %>% #' # predict resistance of cefotaxime for next years #' rsi_predict(col_ab = "cfot", #' col_date = "date", #' year_max = 2025, #' preserve_measurements = FALSE) #' rsi_predict <- function(tbl, col_ab, col_date, year_max = as.integer(format(as.Date(Sys.Date()), '%Y')) + 15, year_every = 1, model = 'binomial', I_as_R = TRUE, preserve_measurements = TRUE, info = TRUE) { if (nrow(tbl) == 0) { stop('This table does not contain any observations.') } if (!col_ab %in% colnames(tbl)) { stop('Column ', col_ab, ' not found.') } if (!col_date %in% colnames(tbl)) { stop('Column ', col_date, ' not found.') } if ('grouped_df' %in% class(tbl)) { # no grouped tibbles please, mutate will throw errors tbl <- base::as.data.frame(tbl, stringsAsFactors = FALSE) } if (I_as_R == TRUE) { tbl[, col_ab] <- gsub('I', 'R', tbl %>% pull(col_ab)) } if (!all(tbl %>% pull(col_ab) %>% as.rsi() %in% c(NA, 'S', 'I', 'R'))) { stop('Column ', col_ab, ' must contain antimicrobial interpretations (S, I, R).') } year <- function(x) { if (all(grepl('^[0-9]{4}$', x))) { x } else { as.integer(format(as.Date(x), '%Y')) } } years_predict <- seq(from = min(year(tbl %>% pull(col_date))), to = year_max, by = year_every) df <- tbl %>% mutate(year = year(tbl %>% pull(col_date))) %>% group_by_at(c('year', col_ab)) %>% summarise(n()) colnames(df) <- c('year', 'antibiotic', 'count') df <- df %>% reshape2::dcast(year ~ antibiotic, value.var = 'count') if (model %in% c('binomial', 'binom', 'logit')) { logitmodel <- with(df, glm(cbind(R, S) ~ year, family = binomial)) if (info == TRUE) { cat('\nLogistic regression model (logit) with binomial distribution') cat('\n------------------------------------------------------------\n') print(summary(logitmodel)) } predictmodel <- stats::predict(logitmodel, newdata = with(df, list(year = years_predict)), type = "response", se.fit = TRUE) prediction <- predictmodel$fit se <- predictmodel$se.fit } else if (model == 'loglin') { loglinmodel <- with(df, glm(R ~ year, family = poisson)) if (info == TRUE) { cat('\nLog-linear regression model (loglin) with poisson distribution') cat('\n--------------------------------------------------------------\n') print(summary(loglinmodel)) } predictmodel <- stats::predict(loglinmodel, newdata = with(df, list(year = years_predict)), type = "response", se.fit = TRUE) prediction <- predictmodel$fit se <- predictmodel$se.fit } else if (model %in% c('lin', 'linear')) { linmodel <- with(df, lm((R / (R + S)) ~ year)) if (info == TRUE) { cat('\nLinear regression model') cat('\n-----------------------\n') print(summary(linmodel)) } predictmodel <- stats::predict(linmodel, newdata = with(df, list(year = years_predict)), se.fit = TRUE) prediction <- predictmodel$fit se <- predictmodel$se.fit } else { stop('No valid model selected.') } # prepare the output dataframe prediction <- data.frame(year = years_predict, probR = prediction, stringsAsFactors = FALSE) prediction$se_min <- prediction$probR - se prediction$se_max <- prediction$probR + se if (model == 'loglin') { prediction$probR <- prediction$probR %>% format(scientific = FALSE) %>% as.integer() prediction$se_min <- prediction$se_min %>% as.integer() prediction$se_max <- prediction$se_max %>% as.integer() colnames(prediction) <- c('year', 'amountR', 'se_max', 'se_min') } else { prediction$se_max[which(prediction$se_max > 1)] <- 1 } prediction$se_min[which(prediction$se_min < 0)] <- 0 total <- prediction if (preserve_measurements == TRUE) { # geschatte data vervangen door gemeten data if (I_as_R == TRUE) { if (!'I' %in% colnames(df)) { df$I <- 0 } df$probR <- df$R / rowSums(df[, c('R', 'S', 'I')]) } else { df$probR <- df$R / rowSums(df[, c('R', 'S')]) } measurements <- data.frame(year = df$year, probR = df$probR, se_min = NA, se_max = NA, stringsAsFactors = FALSE) colnames(measurements) <- colnames(prediction) prediction <- prediction %>% filter(!year %in% df$year) total <- rbind(measurements, prediction) } total }