diff --git a/.gitignore b/.gitignore
index 5fac0fbc..e4a31cd9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -3,3 +3,4 @@
 .RData
 .Ruserdata
 AMR.Rproj
+tests/testthat/Rplots.pdf
diff --git a/.travis.yml b/.travis.yml
index f360382c..fa96253a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -3,15 +3,9 @@
 # Setting up R deps
 language: r
 r: 3.2
-r_packages:
-  - covr
-  - testthat
-  - dplyr
-  - rvest
-  - xml2
-  - reshape2
+r_packages: covr
 
-# system deps
+# system deps, install xclip for clipboard support
 os:
   - linux
   - osx
diff --git a/DESCRIPTION b/DESCRIPTION
index e03a4340..90290f58 100644
--- a/DESCRIPTION
+++ b/DESCRIPTION
@@ -1,6 +1,6 @@
 Package: AMR
 Version: 0.1.2
-Date: 2018-03-27
+Date: 2018-04-02
 Title: Antimicrobial Resistance Analysis
 Authors@R: c(
     person(
diff --git a/R/clipboard.R b/R/clipboard.R
index 48f0f785..e41c2842 100644
--- a/R/clipboard.R
+++ b/R/clipboard.R
@@ -29,27 +29,39 @@ clipboard_import <- function(sep = '\t',
     file <- pipe("xclip -o", "r")
     on.exit(close(file))
   }
-  
-  import_tbl <- read.delim(file = file,
-                           sep = sep,
-                           header = header,
-                           strip.white = TRUE,
-                           dec = dec,
-                           na.strings = na,
-                           fileEncoding = 'UTF-8',
-                           encoding = 'UTF-8',
-                           stringsAsFactors = FALSE)
-  
+
+  import_tbl <- tryCatch(read.delim(file = file,
+                                    sep = sep,
+                                    header = header,
+                                    strip.white = TRUE,
+                                    dec = dec,
+                                    na.strings = na,
+                                    fileEncoding = 'UTF-8',
+                                    encoding = 'UTF-8',
+                                    stringsAsFactors = FALSE),
+                         error = function(e) {
+                           FALSE
+                         })
+
+  if (import_tbl == FALSE) {
+    cat("No clipboard content found.")
+    if (Sys.info()['sysname'] %like% "Linux") {
+      cat(" These functions do not work without X11 installed.")
+    }
+    cat("\n")
+    return(invisible())
+  }
+
   # use tibble, so column types will be translated correctly
   import_tbl <- as_tibble(import_tbl)
-  
+
   if (startrow > 1) {
     # would else lose column headers
     import_tbl <- import_tbl[startrow:nrow(import_tbl),]
   }
-  
+
   colnames(import_tbl) <- gsub('[.]+', '_', colnames(import_tbl))
-  
+
   if (NCOL(import_tbl) == 1 & as_vector == TRUE) {
     import_tbl %>% pull(1)
   } else {
@@ -66,14 +78,14 @@ clipboard_export <- function(x,
                              na = "",
                              header = TRUE,
                              info = TRUE) {
-  
+
   x <- deparse(substitute(x))
   size <- x %>%
-    get() %>% 
+    get() %>%
     object.size() %>%
     formatC(format = 'd') %>%
     as.integer()
-  
+
   x <- get(x)
 
   if (is_Windows() == TRUE) {
@@ -86,18 +98,22 @@ clipboard_export <- function(x,
     on.exit(close(file))
   }
 
-  write.table(x = x,
-              file = file,
-              sep = sep,
-              na = na,
-              row.names = FALSE,
-              col.names = header,
-              dec = dec,
-              quote = FALSE)
+  tryCatch(write.table(x = x,
+                       file = file,
+                       sep = sep,
+                       na = na,
+                       row.names = FALSE,
+                       col.names = header,
+                       dec = dec,
+                       quote = FALSE),
+           error = function(e) {
+             FALSE
+           })
 
   if (info == TRUE) {
     cat("Successfully exported to clipboard:", NROW(x), "obs. of", NCOL(x), "variables.\n")
   }
+
 }
 
 is_Windows <- function() {
@@ -105,6 +121,10 @@ is_Windows <- function() {
 }
 check_xclip <- function() {
   if (!isTRUE(file.exists(Sys.which("xclip")[1L]))) {
+    if (Sys.info()['sysname'] %like% "Linux") {
       stop("Please install Linux package xclip first.")
+    } else {
+      stop("Please install package xclip first (use `brew install xclip on macOS`).")
+    }
   }
 }
diff --git a/R/data.R b/R/data.R
index a8494f3a..91c7a527 100644
--- a/R/data.R
+++ b/R/data.R
@@ -42,7 +42,7 @@
 #' @seealso \code{\link{microorganisms}}
 # last two columns created with:
 # antibiotics %>%
-#   mutate(useful_gramnegative = 
+#   mutate(useful_gramnegative =
 #            if_else(
 #              atc_group1 %like% '(fusidic|glycopeptide|macrolide|lincosamide|daptomycin|linezolid)' |
 #                atc_group2 %like% '(fusidic|glycopeptide|macrolide|lincosamide|daptomycin|linezolid)' |
@@ -116,39 +116,39 @@
 #' # ----------- #
 #' # PREPARATION #
 #' # ----------- #
-#' 
+#'
 #' # Save this example dataset to an object, so we can edit it:
 #' my_data <- septic_patients
-#' 
+#'
 #' # load the dplyr package to make data science A LOT easier
 #' library(dplyr)
-#' 
+#'
 #' # Add first isolates to our dataset:
-#' my_data <- my_data %>% 
-#'   mutate(first_isolates = first_isolate(my_data, date, patient_id, bactid))
-#' 
+#' my_data <- my_data %>%
+#'   mutate(first_isolates = first_isolate(my_data, "date", "patient_id", "bactid"))
+#'
 #' # -------- #
 #' # ANALYSIS #
 #' # -------- #
-#' 
-#' # 1. Get the amoxicillin resistance percentages 
+#'
+#' # 1. Get the amoxicillin resistance percentages
 #' #    of E. coli, divided by hospital:
-#' 
+#'
 #' my_data %>%
 #'   filter(bactid == "ESCCOL",
-#'          first_isolates == TRUE) %>% 
-#'   group_by(hospital_id) %>% 
+#'          first_isolates == TRUE) %>%
+#'   group_by(hospital_id) %>%
 #'   summarise(n = n(),
 #'             amoxicillin_resistance = rsi(amox))
-#'   
-#'   
-#' # 2. Get the amoxicillin/clavulanic acid resistance 
+#'
+#'
+#' # 2. Get the amoxicillin/clavulanic acid resistance
 #' #    percentages of E. coli, trend over the years:
-#' 
-#' my_data %>% 
+#'
+#' my_data %>%
 #'   filter(bactid == guess_bactid("E. coli"),
-#'          first_isolates == TRUE) %>% 
-#'   group_by(year = format(date, "%Y")) %>% 
+#'          first_isolates == TRUE) %>%
+#'   group_by(year = format(date, "%Y")) %>%
 #'   summarise(n = n(),
 #'             amoxclav_resistance = rsi(amcl, minimum = 20))
 "septic_patients"
diff --git a/R/first_isolates.R b/R/first_isolates.R
index f5f04fba..54a2ca5e 100644
--- a/R/first_isolates.R
+++ b/R/first_isolates.R
@@ -18,14 +18,14 @@
 
 #' Determine first (weighted) isolates
 #'
-#' Determine first (weighted) isolates of all microorganisms of every patient per episode and (if needed) per specimen type. 
+#' Determine first (weighted) isolates of all microorganisms of every patient per episode and (if needed) per specimen type.
 #' @param tbl a \code{data.frame} containing isolates.
-#' @param col_date column name of the result date (or date that is was received on the lab), supports tidyverse-like quotation
-#' @param col_patient_id column name of the unique IDs of the patients, supports tidyverse-like quotation
-#' @param col_bactid column name of the unique IDs of the microorganisms (should occur in the \code{\link{microorganisms}} dataset), supports tidyverse-like quotation
+#' @param col_date column name of the result date (or date that is was received on the lab)
+#' @param col_patient_id column name of the unique IDs of the patients
+#' @param col_bactid column name of the unique IDs of the microorganisms (should occur in the \code{\link{microorganisms}} dataset)
 #' @param col_testcode column name of the test codes. Use \code{col_testcode = NA} to \strong{not} exclude certain test codes (like test codes for screening). In that case \code{testcodes_exclude} will be ignored. Supports tidyverse-like quotation.
-#' @param col_specimen column name of the specimen type or group, supports tidyverse-like quotation
-#' @param col_icu column name of the logicals (\code{TRUE}/\code{FALSE}) whether a ward or department is an Intensive Care Unit (ICU), supports tidyverse-like quotation
+#' @param col_specimen column name of the specimen type or group
+#' @param col_icu column name of the logicals (\code{TRUE}/\code{FALSE}) whether a ward or department is an Intensive Care Unit (ICU)
 #' @param col_keyantibiotics column name of the key antibiotics to determine first \emph{weighted} isolates, see \code{\link{key_antibiotics}}. Supports tidyverse-like quotation.
 #' @param episode_days episode in days after which a genus/species combination will be determined as 'first isolate' again
 #' @param testcodes_exclude character vector with test codes that should be excluded (case-insensitive)
@@ -36,8 +36,8 @@
 #' @param ignore_I logical to determine whether antibiotic interpretations with \code{"I"} will be ignored when \code{type = "keyantibiotics"}, see Details
 #' @param points_threshold points until the comparison of key antibiotics will lead to inclusion of an isolate when \code{type = "points"}, see Details
 #' @param info print progress
-#' @param col_genus (deprecated, use \code{col_bactid} instead) column name of the genus of the microorganisms, supports tidyverse-like quotation
-#' @param col_species (deprecated, use \code{col_bactid} instead) column name of the species of the microorganisms, supports tidyverse-like quotation
+#' @param col_genus (deprecated, use \code{col_bactid} instead) column name of the genus of the microorganisms
+#' @param col_species (deprecated, use \code{col_bactid} instead) column name of the species of the microorganisms
 #' @details \strong{WHY THIS IS SO IMPORTANT} \cr
 #'     To conduct an analysis of antimicrobial resistance, you should only include the first isolate of every patient per episode \href{https://www.ncbi.nlm.nih.gov/pubmed/17304462}{[1]}. If you would not do this, you could easily get an overestimate or underestimate of the resistance of an antibiotic. Imagine that a patient was admitted with an MRSA and that it was found in 5 different blood cultures the following week. The resistance percentage of oxacillin of all \emph{S. aureus} isolates would be overestimated, because you included this MRSA more than once. It would be \href{https://en.wikipedia.org/wiki/Selection_bias}{selection bias}.
 #'
@@ -54,15 +54,13 @@
 #' # septic_patients is a dataset available in the AMR package
 #' ?septic_patients
 #' my_patients <- septic_patients
-#' 
+#'
 #' library(dplyr)
 #' my_patients$first_isolate <- my_patients %>%
-#'   left_join_microorganisms() %>%
-#'   first_isolate(col_date = date,
-#'                 col_patient_id = patient_id,
-#'                 col_genus = genus,
-#'                 col_species = species)
-#'                 
+#'   first_isolate(col_date = "date",
+#'                 col_patient_id = "patient_id",
+#'                 col_bactid = "bactid")
+#'
 #' \dontrun{
 #'
 #' # set key antibiotics to a new variable
@@ -121,31 +119,25 @@ first_isolate <- function(tbl,
                           info = TRUE,
                           col_genus = NA,
                           col_species = NA) {
-  
-  # support tidyverse-like quotation
-  # col_date <- quasiquotate(deparse(substitute(col_date)), col_date)
-  # col_patient_id <- quasiquotate(deparse(substitute(col_patient_id)), col_patient_id)
-  # col_bactid <- quasiquotate(deparse(substitute(col_bactid)), col_bactid)
-  # col_genus <- quasiquotate(deparse(substitute(col_genus)), col_genus)
-  # col_species <- quasiquotate(deparse(substitute(col_species)), col_species)
-  # col_testcode <- quasiquotate(deparse(substitute(col_testcode)), col_testcode)
-  # col_specimen <- quasiquotate(deparse(substitute(col_specimen)), col_specimen)
-  # col_icu <- quasiquotate(deparse(substitute(col_icu)), col_icu)
-  # col_keyantibiotics <- quasiquotate(deparse(substitute(col_keyantibiotics)), col_keyantibiotics)
-  
+
+  # bactid OR genus+species must be available
+  if (is.na(col_bactid) & (is.na(col_genus) | is.na(col_species))) {
+    stop('`col_bactid or both `col_genus` and `col_species` must be available.')
+  }
+
   # check if columns exist
   check_columns_existance <- function(column, tblname = tbl) {
     if (NROW(tblname) <= 1 | NCOL(tblname) <= 1) {
       stop('Please check tbl for existance.')
     }
-    
+
     if (!is.na(column)) {
       if (!(column %in% colnames(tblname))) {
-        stop('Column ', column, ' not found.')
+        stop('Column `', column, '` not found.')
       }
     }
   }
-  
+
   check_columns_existance(col_date)
   check_columns_existance(col_patient_id)
   check_columns_existance(col_bactid)
@@ -154,13 +146,13 @@ first_isolate <- function(tbl,
   check_columns_existance(col_testcode)
   check_columns_existance(col_icu)
   check_columns_existance(col_keyantibiotics)
-  
+
   if (!is.na(col_bactid)) {
-    tbl <- tbl %>% left_join_microorganisms()
+    tbl <- tbl %>% left_join_microorganisms(by = col_bactid)
     col_genus <- "genus"
     col_species <- "species"
   }
-  
+
   if (is.na(col_testcode)) {
     testcodes_exclude <- NA
   }
@@ -168,18 +160,18 @@ first_isolate <- function(tbl,
   if (!is.na(testcodes_exclude[1]) & testcodes_exclude[1] != '' & info == TRUE) {
     cat('Isolates from these test codes will be ignored:\n', toString(testcodes_exclude), '\n')
   }
-  
+
   if (is.na(col_icu)) {
     icu_exclude <- FALSE
   } else {
     tbl <- tbl %>%
       mutate(col_icu = tbl %>% pull(col_icu) %>% as.logical())
   }
-  
+
   if (is.na(col_specimen)) {
     filter_specimen <- ''
   }
-  
+
   specgroup.notice <- ''
   weighted.notice <- ''
   # filter on specimen group and keyantibiotics when they are filled in
@@ -196,11 +188,11 @@ first_isolate <- function(tbl,
   } else {
     tbl <- tbl %>% mutate(key_ab = tbl %>% pull(col_keyantibiotics))
   }
-  
+
   if (is.na(testcodes_exclude[1])) {
     testcodes_exclude <- ''
   }
-  
+
   # create new dataframe with original row index and right sorting
   tbl <- tbl %>%
     mutate(first_isolate_row_index = 1:nrow(tbl),
@@ -211,9 +203,9 @@ first_isolate <- function(tbl,
            genus = tbl %>% pull(col_genus)) %>%
     mutate(species = if_else(is.na(species), '', species),
            genus = if_else(is.na(genus), '', genus))
-  
+
   if (filter_specimen == '') {
-    
+
     if (icu_exclude == FALSE) {
       if (info == TRUE) {
         cat('Isolates from ICU will *NOT* be ignored.\n')
@@ -235,7 +227,7 @@ first_isolate <- function(tbl,
                      col_genus,
                      col_species,
                      col_date))
-      
+
       suppressWarnings(
         row.start <- which(tbl %>% pull(col_icu) == FALSE) %>% min(na.rm = TRUE)
       )
@@ -243,7 +235,7 @@ first_isolate <- function(tbl,
         row.end <- which(tbl %>% pull(col_icu) == FALSE) %>% max(na.rm = TRUE)
       )
     }
-    
+
   } else {
     # sort on specimen and only analyse these row to save time
     if (icu_exclude == FALSE) {
@@ -282,9 +274,9 @@ first_isolate <- function(tbl,
                          & tbl %>% pull(col_icu) == FALSE) %>% max(na.rm = TRUE)
       )
     }
-    
+
   }
-  
+
   if (abs(row.start) == Inf | abs(row.end) == Inf) {
     if (info == TRUE) {
       cat('No isolates found.\n')
@@ -297,14 +289,14 @@ first_isolate <- function(tbl,
     }
     return(tbl %>% pull(real_first_isolate))
   }
-  
+
   scope.size <- tbl %>%
     filter(row_number() %>%
              between(row.start,
                      row.end),
            genus != '') %>%
     nrow()
-  
+
   # Analysis of first isolate ----
   all_first <- tbl %>%
     mutate(other_pat_or_mo = if_else(patient_id == lag(patient_id)
@@ -316,7 +308,7 @@ first_isolate <- function(tbl,
     mutate(days_diff = if_else(other_pat_or_mo == FALSE,
                                (date_lab - lag(date_lab)) + lag(days_diff),
                                0))
-  
+
   if (col_keyantibiotics != '') {
     if (info == TRUE) {
       if (type == 'keyantibiotics') {
@@ -365,7 +357,7 @@ first_isolate <- function(tbl,
             TRUE,
             FALSE))
   }
-  
+
   # first one as TRUE
   all_first[row.start, 'real_first_isolate'] <- TRUE
   # no tests that should be included, or ICU
@@ -375,15 +367,15 @@ first_isolate <- function(tbl,
   if (icu_exclude == TRUE) {
     all_first[which(all_first[, col_icu] == TRUE), 'real_first_isolate'] <- FALSE
   }
-  
+
   # NA's where genus is unavailable
   all_first <- all_first %>%
     mutate(real_first_isolate = if_else(genus == '', NA, real_first_isolate))
-  
+
   all_first <- all_first %>%
     arrange(first_isolate_row_index) %>%
     pull(real_first_isolate)
-  
+
   if (info == TRUE) {
     cat(paste0('\nFound ',
                all_first %>% sum(na.rm = TRUE),
@@ -393,13 +385,13 @@ first_isolate <- function(tbl,
                (all_first %>% sum(na.rm = TRUE) / tbl %>% nrow()) %>% percent(),
                ' of total)\n'))
   }
-  
+
   if (output_logical == FALSE) {
     all_first <- all_first %>% as.integer()
   }
-  
+
   all_first
-  
+
 }
 
 #' Key antibiotics based on bacteria ID
@@ -409,10 +401,10 @@ first_isolate <- function(tbl,
 #' @param info print warnings
 #' @param amcl,amox,cfot,cfta,cftr,cfur,cipr,clar,clin,clox,doxy,gent,line,mero,peni,pita,rifa,teic,trsu,vanc column names of antibiotics, case-insensitive
 #' @export
-#' @importFrom dplyr %>% mutate if_else 
+#' @importFrom dplyr %>% mutate if_else
 #' @return Character of length 1.
 #' @seealso \code{\link{mo_property}} \code{\link{antibiotics}}
-#' @examples 
+#' @examples
 #' \donttest{
 #' #' # set key antibiotics to a new variable
 #' tbl$keyab <- key_antibiotics(tbl)
@@ -440,9 +432,9 @@ key_antibiotics <- function(tbl,
                             teic = 'teic',
                             trsu = 'trsu',
                             vanc = 'vanc') {
-  
+
   keylist <- character(length = nrow(tbl))
-  
+
   # check columns
   col.list <- c(amox, cfot, cfta, cftr, cfur, cipr, clar,
                 clin, clox, doxy, gent, line, mero, peni,
@@ -486,12 +478,12 @@ key_antibiotics <- function(tbl,
   teic <- col.list[17]
   trsu <- col.list[18]
   vanc <- col.list[19]
-  
+
   # join microorganisms
   tbl <- tbl %>% left_join_microorganisms(col_bactid)
-  
+
   tbl$key_ab <- NA_character_
-  
+
   # Staphylococcus
   list_ab <- c(clox, trsu, teic, vanc, doxy, line, clar, rifa)
   list_ab <- list_ab[list_ab %in% colnames(tbl)]
@@ -501,7 +493,7 @@ key_antibiotics <- function(tbl,
                                         MARGIN = 1,
                                         FUN = function(x) paste(x, collapse = "")),
                                   key_ab))
-  
+
   # Rest of Gram +
   list_ab <- c(peni, amox, teic, vanc, clin, line, clar, trsu)
   list_ab <- list_ab[list_ab %in% colnames(tbl)]
@@ -511,7 +503,7 @@ key_antibiotics <- function(tbl,
                                         MARGIN = 1,
                                         FUN = function(x) paste(x, collapse = "")),
                                   key_ab))
-  
+
   # Gram -
   list_ab <- c(amox, amcl, pita, cfur, cfot, cfta, cftr, mero, cipr, trsu, gent)
   list_ab <- list_ab[list_ab %in% colnames(tbl)]
@@ -521,76 +513,76 @@ key_antibiotics <- function(tbl,
                                         MARGIN = 1,
                                         FUN = function(x) paste(x, collapse = "")),
                                   key_ab))
-  
+
   # format
   tbl <- tbl %>%
     mutate(key_ab = gsub('(NA|NULL)', '-', key_ab) %>% toupper())
-  
+
   tbl$key_ab
-  
+
 }
 
 #' @importFrom dplyr progress_estimated %>%
 #' @noRd
 key_antibiotics_equal <- function(x,
-                                  y, 
-                                  type = c("keyantibiotics", "points"), 
+                                  y,
+                                  type = c("keyantibiotics", "points"),
                                   ignore_I = TRUE,
-                                  points_threshold = 2, 
+                                  points_threshold = 2,
                                   info = FALSE) {
   # x is active row, y is lag
 
   type <- type[1]
-  
+
   if (length(x) != length(y)) {
     stop('Length of `x` and `y` must be equal.')
   }
-  
+
   result <- logical(length(x))
-  
+
   if (info == TRUE) {
     p <- dplyr::progress_estimated(length(x))
   }
-  
+
   for (i in 1:length(x)) {
-    
+
     if (info == TRUE) {
       p$tick()$print()
     }
-    
+
     if (is.na(x[i])) {
       x[i] <- ''
     }
     if (is.na(y[i])) {
       y[i] <- ''
     }
-    
+
     if (nchar(x[i]) != nchar(y[i])) {
-      
+
       result[i] <- FALSE
-      
+
     } else if (x[i] == '' & y[i] == '') {
-      
+
       result[i] <- TRUE
-      
+
     } else {
-      
+
       x2 <- strsplit(x[i], "")[[1]]
       y2 <- strsplit(y[i], "")[[1]]
-      
+
       if (type == 'points') {
         # count points for every single character:
         # - no change is 0 points
         # - I <-> S|R is 0.5 point
         # - S|R <-> R|S is 1 point
         # use the levels of as.rsi (S = 1, I = 2, R = 3)
-        
+
         suppressWarnings(x2 <- x2 %>% as.rsi() %>% as.double())
         suppressWarnings(y2 <- y2 %>% as.rsi() %>% as.double())
-        
+
         points <- (x2 - y2) %>% abs() %>% sum(na.rm = TRUE)
         result[i] <- ((points / 2) >= points_threshold)
-        
+
       } else if (type == 'keyantibiotics') {
         # check if key antibiotics are exactly the same
         # also possible to ignore I, so only S <-> R and S <-> R are counted
@@ -599,15 +591,15 @@ key_antibiotics_equal <- function(x,
         } else {
           valid_chars <- c('S', 's', 'I', 'i', 'R', 'r')
         }
-        
+
         # remove invalid values (like "-", NA) on both locations
         x2[which(!x2 %in% valid_chars)] <- '?'
         x2[which(!y2 %in% valid_chars)] <- '?'
         y2[which(!x2 %in% valid_chars)] <- '?'
         y2[which(!y2 %in% valid_chars)] <- '?'
-        
+
         result[i] <- all(x2 == y2)
-        
+
       } else {
         stop('`', type, '` is not a valid value for type, must be "points" or "keyantibiotics". See ?first_isolate.')
       }
@@ -627,7 +619,7 @@ key_antibiotics_equal <- function(x,
 #' @importFrom dplyr %>% filter slice pull
 #' @return Character (vector).
 #' @seealso \code{\link{microorganisms}} for the dataframe that is being used to determine ID's.
-#' @examples 
+#' @examples
 #' # These examples all return "STAAUR", the ID of S. aureus:
 #' guess_bactid("stau")
 #' guess_bactid("STAU")
@@ -646,7 +638,7 @@ guess_bactid <- function(x) {
   # add start and stop
   x_species <- paste(x, 'species')
   x <- paste0('^', x, '$')
-  
+
   for (i in 1:length(x)) {
     if (tolower(x[i]) == '^e.*coli$') {
       # avoid detection of Entamoeba coli in case of E. coli
@@ -681,7 +673,7 @@ guess_bactid <- function(x) {
 
     # let's try the ID's first
     found <- AMR::microorganisms %>% filter(bactid == x.bak[i])
-    
+
     if (nrow(found) == 0) {
       # now try exact match
       found <- AMR::microorganisms %>% filter(fullname == x[i])
@@ -709,10 +701,10 @@ guess_bactid <- function(x) {
                      x.bak[i] %>% substr((x_length / 2) + 1, x_length) %>% trimws())
       found <- AMR::microorganisms %>% filter(fullname %like% paste0('^', x[i]))
     }
-    
+
     if (nrow(found) != 0) {
-      x[i] <- found %>% 
-        slice(1) %>% 
+      x[i] <- found %>%
+        slice(1) %>%
         pull(bactid)
     } else {
       x[i] <- ""
diff --git a/R/join.R b/R/join.R
index 9dfc516b..c22a0953 100644
--- a/R/join.R
+++ b/R/join.R
@@ -10,12 +10,12 @@
 #' @param ... other parameters to pass on to \code{dplyr::\link[dplyr]{join}}.
 #' @details As opposed to the \code{\link[dplyr]{join}} functions of \code{dplyr}, characters vectors are supported and at default existing columns will get a suffix \code{"2"} and the newly joined columns will not get a suffix. See \code{\link[dplyr]{join}} for more information.
 #' @export
-#' @examples 
+#' @examples
 #' left_join_microorganisms("STAAUR")
-#' 
+#'
 #' library(dplyr)
 #' septic_patients %>% left_join_microorganisms()
-#' 
+#'
 #' df <- data.frame(date = seq(from = as.Date("2018-01-01"),
 #'                             to = as.Date("2018-01-07"),
 #'                             by = 1),
diff --git a/man/clipboard.Rd b/man/clipboard.Rd
index 15239f67..387a1a3e 100644
--- a/man/clipboard.Rd
+++ b/man/clipboard.Rd
@@ -41,7 +41,7 @@ clipboard_export(x, sep = "\\t", dec = ".", na = "", header = TRUE,
 data.frame
 }
 \description{
-These are helper functions around \code{\link{read.table}} and \code{\link{write.table}} to import from and export to clipboard. The data will be read and written as tab-separated by default, which makes it possible to copy and paste from other software like Excel and SPSS without further transformation.
+These are helper functions around \code{\link{read.table}} and \code{\link{write.table}} to import from and export to clipboard, with support for Windows, Linux and macOS. The data will be read and written as tab-separated by default, which makes it possible to copy and paste from other software like Excel and SPSS without further transformation.
 }
 \details{
 For \code{clipboard_export}, the reserved clipboard size for exporting will be set automatically to 125\% of the object size of \code{x}. This way, it is possible to export data with thousands of rows as the only limit will be your systems RAM.
diff --git a/man/first_isolate.Rd b/man/first_isolate.Rd
index 0b11f33c..9fe300a2 100644
--- a/man/first_isolate.Rd
+++ b/man/first_isolate.Rd
@@ -14,17 +14,17 @@ first_isolate(tbl, col_date, col_patient_id, col_bactid = NA,
 \arguments{
 \item{tbl}{a \code{data.frame} containing isolates.}
 
-\item{col_date}{column name of the result date (or date that is was received on the lab), supports tidyverse-like quotation}
+\item{col_date}{column name of the result date (or date that is was received on the lab)}
 
-\item{col_patient_id}{column name of the unique IDs of the patients, supports tidyverse-like quotation}
+\item{col_patient_id}{column name of the unique IDs of the patients}
 
-\item{col_bactid}{column name of the unique IDs of the microorganisms (should occur in the \code{\link{microorganisms}} dataset), supports tidyverse-like quotation}
+\item{col_bactid}{column name of the unique IDs of the microorganisms (should occur in the \code{\link{microorganisms}} dataset)}
 
 \item{col_testcode}{column name of the test codes. Use \code{col_testcode = NA} to \strong{not} exclude certain test codes (like test codes for screening). In that case \code{testcodes_exclude} will be ignored. Supports tidyverse-like quotation.}
 
-\item{col_specimen}{column name of the specimen type or group, supports tidyverse-like quotation}
+\item{col_specimen}{column name of the specimen type or group}
 
-\item{col_icu}{column name of the logicals (\code{TRUE}/\code{FALSE}) whether a ward or department is an Intensive Care Unit (ICU), supports tidyverse-like quotation}
+\item{col_icu}{column name of the logicals (\code{TRUE}/\code{FALSE}) whether a ward or department is an Intensive Care Unit (ICU)}
 
 \item{col_keyantibiotics}{column name of the key antibiotics to determine first \emph{weighted} isolates, see \code{\link{key_antibiotics}}. Supports tidyverse-like quotation.}
 
@@ -46,9 +46,9 @@ first_isolate(tbl, col_date, col_patient_id, col_bactid = NA,
 
 \item{info}{print progress}
 
-\item{col_genus}{(deprecated, use \code{col_bactid} instead) column name of the genus of the microorganisms, supports tidyverse-like quotation}
+\item{col_genus}{(deprecated, use \code{col_bactid} instead) column name of the genus of the microorganisms}
 
-\item{col_species}{(deprecated, use \code{col_bactid} instead) column name of the species of the microorganisms, supports tidyverse-like quotation}
+\item{col_species}{(deprecated, use \code{col_bactid} instead) column name of the species of the microorganisms}
 }
 \value{
 A vector to add to table, see Examples.
@@ -73,12 +73,10 @@ my_patients <- septic_patients
 
 library(dplyr)
 my_patients$first_isolate <- my_patients \%>\%
-  left_join_microorganisms() \%>\%
-  first_isolate(col_date = date,
-                col_patient_id = patient_id,
-                col_genus = genus,
-                col_species = species)
-                
+  first_isolate(col_date = "date",
+                col_patient_id = "patient_id",
+                col_bactid = "bactid")
+
 \dontrun{
 
 # set key antibiotics to a new variable
diff --git a/man/septic_patients.Rd b/man/septic_patients.Rd
index 8b5176d0..14956c3b 100644
--- a/man/septic_patients.Rd
+++ b/man/septic_patients.Rd
@@ -38,31 +38,31 @@ my_data <- septic_patients
 library(dplyr)
 
 # Add first isolates to our dataset:
-my_data <- my_data \%>\% 
-  mutate(first_isolates = first_isolate(my_data, date, patient_id, bactid))
+my_data <- my_data \%>\%
+  mutate(first_isolates = first_isolate(my_data, "date", "patient_id", "bactid"))
 
 # -------- #
 # ANALYSIS #
 # -------- #
 
-# 1. Get the amoxicillin resistance percentages 
+# 1. Get the amoxicillin resistance percentages
 #    of E. coli, divided by hospital:
 
 my_data \%>\%
   filter(bactid == "ESCCOL",
-         first_isolates == TRUE) \%>\% 
-  group_by(hospital_id) \%>\% 
+         first_isolates == TRUE) \%>\%
+  group_by(hospital_id) \%>\%
   summarise(n = n(),
             amoxicillin_resistance = rsi(amox))
-  
-  
-# 2. Get the amoxicillin/clavulanic acid resistance 
+
+
+# 2. Get the amoxicillin/clavulanic acid resistance
 #    percentages of E. coli, trend over the years:
 
-my_data \%>\% 
+my_data \%>\%
   filter(bactid == guess_bactid("E. coli"),
-         first_isolates == TRUE) \%>\% 
-  group_by(year = format(date, "\%Y")) \%>\% 
+         first_isolates == TRUE) \%>\%
+  group_by(year = format(date, "\%Y")) \%>\%
   summarise(n = n(),
             amoxclav_resistance = rsi(amcl, minimum = 20))
 }
diff --git a/tests/testthat/Rplots.pdf b/tests/testthat/Rplots.pdf
deleted file mode 100644
index 386c2865..00000000
Binary files a/tests/testthat/Rplots.pdf and /dev/null differ
diff --git a/tests/testthat/test-clipboard.R b/tests/testthat/test-clipboard.R
index 3385f15a..668c427e 100644
--- a/tests/testthat/test-clipboard.R
+++ b/tests/testthat/test-clipboard.R
@@ -1,9 +1,9 @@
 context("clipboard.R")
 
 test_that("clipboard works", {
-  skip_on_os(c("linux", "solaris"))
   t1 <<- AMR::antibiotics # why is the <<- needed? Won't work without it...
   clipboard_export(t1, info = FALSE)
   t2 <- clipboard_import()
+  skip_if(is.null(t1) | is.null(t2), message = "No clipboard content found: skipping.")
   expect_equal(t1, t2)
 })