diff --git a/mtusFunctions.R b/mtusFunctions.R
index 4299ab4798eaf02a681d97f85dd3092aa94f79a3..6c30475e5d8d2b05b95d66064e073697398f0f10 100644
--- a/mtusFunctions.R
+++ b/mtusFunctions.R
@@ -17,7 +17,8 @@ lb_myRequiredPackages <- function(x,y){
 }
 
 # Use the function to load the libraries required by this code
-reqLibs <- c("data.table" # fast data munching
+reqLibs <- c("data.table", # fast data munching
+             "openssl" # for hashing ids
 )
 
 print(paste0("Loading the following libraries using lb_myRequiredPackages: ", reqLibs))
@@ -30,6 +31,33 @@ ba_tidyNum <- function(number) {
   format(number, big.mark=",", scientific=FALSE)
 }
 
+###
+ba_MTUScreateIds <- function(dt){
+  # create a unique pid & unique diary pid that will be unique across all years
+  dt <- dt[, ba_pidChar := paste0(survey, swave, msamp, hldid,persid,sep= "_")] # force character
+  dt <- dt[, ba_pid := md5(ba_pidChar)] # hash
+  dt <- dt[, ba_diarypid := paste0(ba_pid, id, sep= "_")] # force character
+}
+
+# # diarypid
+# mtusUKEpsDT$ba_diarypid <-
+#   group_indices(mtusUKEpsDT, survey,
+#                 swave,
+#                 msamp,
+#                 hldid,
+#                 persid,
+#                 id
+#   )
+# 
+# # pid
+# mtusUKEpsDT$ba_pid <-
+#   group_indices(mtusUKEpsDT, survey,
+#                 swave,
+#                 msamp,
+#                 hldid,
+#                 persid
+#   )
+
 ###
 ba_MTUScreateEpisodeStartEndDateTimes <- function(dt){  
   # Setting up corrected start and end timestamps
@@ -53,8 +81,8 @@ ba_MTUScreateAllEpisodeStartTimesAsString <- function(dt){
   # start time as string
   # Use the fake start time we created earlier which includes all cases
   dt <- dt[, st_hour := as.POSIXlt(dt$r_epStartDateTime)$hour]
-  dt <- dt[, st_mins := as.POSIXlt(mtusUKEpsDT$r_epStartDateTime)$min]
-  dt <- dt[, str_epStartTime := paste0(dt$st_hour, 
+  dt <- dt[, st_mins := as.POSIXlt(dt$r_epStartDateTime)$min]
+  dt <- dt[, r_epStartTimeStr := paste0(dt$st_hour, 
                                            ":",
                                            dt$st_mins
                                            )