diff --git a/NAMESPACE b/NAMESPACE
index 020ffb9..ef0e530 100644
--- a/NAMESPACE
+++ b/NAMESPACE
@@ -18,7 +18,6 @@ export(format_stats_results)
 export(group_ep_for_targets)
 export(index_expanded_ep_groups)
 export(index_non_null_group_level)
-export(join_adam)
 export(llist)
 export(load_debug_session)
 export(mk_endpoint_str)
diff --git a/R/add_event_index.R b/R/add_event_index.R
index c99d75c..76a9deb 100644
--- a/R/add_event_index.R
+++ b/R/add_event_index.R
@@ -42,6 +42,8 @@ create_flag <- function(dat, var_value_pairs=NULL, singletons=NULL) {
 #'   of the columns `pop_var`, `pop_value`, `period_var`, `period_value`,
 #'   `endpoint_filter`, `endpoint_group_filter`, and `custom_pop_filter`, which
 #'   are used to define the conditions for event indexing.
+#' 
+#' @param analysis_data_container A data.table containing the analysis data.
 #'
 #' @return A `data.table` similar to the input but with an additional
 #'   `event_index` column, which contains the indices of events as determined by
diff --git a/R/add_id.R b/R/add_id.R
index 39f32a1..c22d52f 100644
--- a/R/add_id.R
+++ b/R/add_id.R
@@ -1,6 +1,6 @@
 #' Add ID to user-defined endpoint groups
 #'
-#' @param ep
+#' @param ep A `data.table` containing endpoint definitions.
 #'
 #' @return data.table
 #' @export
diff --git a/R/apply_criterion.R b/R/apply_criterion.R
index aa1260b..2ab1ff0 100644
--- a/R/apply_criterion.R
+++ b/R/apply_criterion.R
@@ -6,6 +6,7 @@
 #'
 #' @param ep A `data.table` containing expanded endpoint definitions and
 #'   associated data, typically the output from `add_event_index`.
+#' @param analysis_data_container data.table containing the analysis data.
 #' @param fn_map A `data.table` mapping endpoint definitions to criterion
 #'   functions.
 #'
@@ -60,6 +61,7 @@ apply_criterion_endpoint <- function(ep, analysis_data_container, fn_map) {
 #'
 #' @param ep A `data.table` containing endpoint data with applied endpoint
 #'   criteria, typically the output from `apply_criterion_endpoint`.
+#' @param analysis_data_container data.table containing the analysis data.
 #' @param fn_map A `data.table` mapping endpoint definitions to by-strata
 #'   criteria functions.
 #' @param type The type of criterion to apply, either
diff --git a/R/apply_stats.R b/R/apply_stats.R
index 4a25dd0..e8e3125 100644
--- a/R/apply_stats.R
+++ b/R/apply_stats.R
@@ -6,7 +6,7 @@
 #'
 #' @param ep A `data.table` containing prepared endpoint data for statistical
 #'   analysis, typically the output from `prepare_for_stats`.
-#' @param fn_map A `data_table` mapping endpoint definitions to statistical
+#' @param analysis_data_container data.table containing the analysis data.
 #'   functions.
 #' @param type The type of statistical function. Can be one of
 #'   "stat_by_strata_by_trt", "stat_by_strata_across_trt", or "stat_across_strata_across_trt"
diff --git a/R/expand_endpoints.R b/R/expand_endpoints.R
index 693a8db..b29d9b5 100644
--- a/R/expand_endpoints.R
+++ b/R/expand_endpoints.R
@@ -11,6 +11,7 @@
 #' @param ep A `data.table` containing endpoint definitions, where each row
 #'   corresponds to a different endpoint and contains relevant attributes such
 #'   as the endpoint name, type, and criteria.
+#' @param analysis_data_container data.table containing the analysis data.
 #' @return A `data.table` where each row corresponds to an expanded endpoint
 #'   definition
 #' @export
@@ -20,16 +21,21 @@ expand_over_endpoints <- function(ep, analysis_data_container) {
   ep_with_data[, expand_specification := llist(define_expanded_ep(dat[[1]], group_by[[1]])),
           by = 1:nrow(ep_with_data)]
   ep_with_data[["dat"]] <- NULL
-  ep_expanded <-
-    ep_with_data %>% tidyr::unnest(col = expand_specification) %>% setDT()
 
-  ep_expanded_2 <- add_missing_columns(ep_expanded)
-  ep_expanded_2[, endpoint_id := add_ep_id(.SD, .BY), by =
-                endpoint_spec_id]
+  # Expand by groups. If no grouping is present, then add empty group related columns
+  if(any(!is.na(ep_with_data$expand_specification))){
+    ep_exp <- ep_with_data %>% tidyr::unnest(col = expand_specification) %>% setDT()
+  }else{
+    ep_exp <- ep_with_data[, .SD, .SDcols = setdiff(names(ep_with_data), "expand_specification")]
+    ep_exp[, endpoint_group_filter := NA]
+    ep_exp[, endpoint_group_metadata := list()]
+  }
+  
+  ep_exp[, endpoint_id := add_ep_id(.SD, .BY), by = endpoint_spec_id]
 
   # Complete endpoint labels by replacing keywords with values
-  nm_set <- names(ep_expanded_2)
-  ep_expanded_2[,endpoint_label_evaluated := apply(ep_expanded_2, 1, function(x){
+  nm_set <- names(ep_exp)
+  ep_exp[,endpoint_label_evaluated := apply(ep_exp, 1, function(x){
 
     xlab <- x[["endpoint_label"]]
 
@@ -61,12 +67,12 @@ expand_over_endpoints <- function(ep, analysis_data_container) {
     }
     return(xlab)
   })]
-  ep_expanded_2[["endpoint_label"]] <- NULL
-  setnames(ep_expanded_2, "endpoint_label_evaluated", "endpoint_label")
+  ep_exp[["endpoint_label"]] <- NULL
+  setnames(ep_exp, "endpoint_label_evaluated", "endpoint_label")
 
   keep <-
     setdiff(
-      names(ep_expanded_2),
+      names(ep_exp),
       c(
         "data_prepare",
         "stat_by_strata_by_trt",
@@ -76,11 +82,12 @@ expand_over_endpoints <- function(ep, analysis_data_container) {
         "crit_by_strata_by_trt",
         "crit_by_strata_across_trt",
         "fn_type",
-        "fn_hash"
+        "fn_hash",
+        "expand_specification"
       )
     )
 
-out <- ep_expanded_2[, .SD, .SDcols=keep]
+out <- ep_exp[, .SD, .SDcols=keep]
 setkey(out, key_analysis_data)
 out[]
 }
@@ -98,6 +105,8 @@ out[]
 #' @param group_by A list specifying the grouping for endpoints, where
 #'   each element corresponds to a variable used for grouping endpoints and
 #'   contains the levels for that grouping variable.
+#' @param forced_group_levels data.table (optional). Table with group levels 
+#'   that must be included in the expansion, regardless of `group_by`.
 #' @param col_prefix A prefix used to create the names of the metadata and
 #'   filter columns in the output `data.table`. Defaults to "endpoint_group".
 #'
@@ -223,25 +232,6 @@ add_ep_id <- function(x, grp) {
   ))]
 }
 
-
-add_missing_columns <- function(x){
-  if(length(intersect(c("endpoint_group_filter", "empty", "endpoint_group_metadata"), names(x)))==2){
-    return(x)
-  }
-  x1 <- copy(x)
-  if(length(intersect(c("endpoint_group_filter"), names(x)))==0){
-    x1[, endpoint_group_filter:=NA]
-  }
-  if(length(intersect(c("empty"), names(x)))==0){
-    x1[, empty:=NA]
-  }
-  if(length(intersect(c("endpoint_group_metadata"), names(x)))==0){
-    x1[, endpoint_group_metadata:=list()]
-  }
-
-  x1
-}
-
 #' Add forced group levels
 #'
 #' @description Expand the set of unique group levels of one grouping variables in a table containing all combinations of one or more grouping variables.
diff --git a/R/mk_endpoint_str.R b/R/mk_endpoint_str.R
index 9d0b71f..549a842 100644
--- a/R/mk_endpoint_str.R
+++ b/R/mk_endpoint_str.R
@@ -3,6 +3,7 @@
 #' @param study_metadata List. Metadata describing the clinical study.
 #' @param pop_var Character.
 #' @param pop_value Character.
+#' @param custom_pop_filter Character.
 #' @param treatment_var Character.
 #' @param treatment_refval Character.
 #' @param period_var Character.
@@ -14,10 +15,12 @@
 #' @param data_prepare List.
 #' @param stat_by_strata_by_trt List.
 #' @param stat_by_strata_across_trt List.
+#' @param stat_across_strata_across_trt List.
 #' @param crit_endpoint List.
 #' @param crit_by_strata_by_trt List.
 #' @param crit_by_strata_across_trt List.
 #' @param only_strata_with_events Boolean.
+#' @param env Environment.
 #'
 #' @return A data.table containing the endpoint specification.
 #' @export
@@ -25,7 +28,7 @@
 mk_endpoint_str <- function(study_metadata = NULL,
                             pop_var = NULL,
                             pop_value = NULL,
-                            custom_pop_filter=NA_character_,
+                            custom_pop_filter = NA_character_,
                             treatment_var = NULL,
                             treatment_refval = NULL,
                             period_var = NA_character_,
diff --git a/R/mk_filtered_endpoint_dt.R b/R/mk_filtered_endpoint_dt.R
index dd2f6d9..da8798a 100644
--- a/R/mk_filtered_endpoint_dt.R
+++ b/R/mk_filtered_endpoint_dt.R
@@ -1,44 +1,3 @@
-#' Filter adam data
-#'
-#' @param ep_unnest data.table. An unnested endpoint definition table
-#' @param adam_db data.table. A table containing the adam datasets associated
-#'   with each data_prepare
-#'
-#' @return a data.table with the filtered adam data.
-#' @export
-#'
-join_adam <-
-  function(ep,
-           ep_fn_map,
-           adam_db,
-           filter_pop = TRUE,
-           filter_period = TRUE,
-           filter_trt = TRUE,
-           filter_user_defined = TRUE) {
-    checkmate::assert_data_table(ep)
-    checkmate::assert_data_table(adam_db)
-
-
-    ep_adam <-
-      merge(ep, ep_fn_map[fn_type == "data_prepare"], by = "endpoint_spec_id")
-
-    ep_adam <-
-      merge(ep_adam,
-            adam_db[, .(fn_hash, dat)],
-            by = "fn_hash",
-            all.x = TRUE,
-            all.y = FALSE)
-    # We no longer need to track the data generating (aka ADaM) functions.
-    # Tracking it, in fact, might increase risk of triggering a unneccessary
-    # re-run in targets if the fn hash changes without any data change
-    keep_cols <-
-      setdiff(names(ep_adam),
-              c("fn_type", "fn", "fn_name", "fn_hash", "fn_callable"))
-    ep_adam[, .SD, .SDcols = keep_cols]
-
-
-  }
-
 #' Filter applying to a data.table
 #'
 #' @param adam_dt data.table::data.table
diff --git a/R/prepare_for_stats.R b/R/prepare_for_stats.R
index d7fa356..a80adfb 100644
--- a/R/prepare_for_stats.R
+++ b/R/prepare_for_stats.R
@@ -9,6 +9,7 @@
 #'   associated data, typically the output from `apply_criterion_by_strata`.
 #' @param fn_map A `data.table` mapping endpoint definitions to statistical
 #'   functions.
+#' @param analysis_data_container data.table containing the analysis data.
 #' @param type A character string specifying the type of statistics for which
 #'   the data is being prepared. Valid types are "stat_by_strata_by_trt",
 #'   "stat_by_strata_across_trt", and "stat_across_strata_across_trt".
@@ -60,7 +61,7 @@ prepare_for_stats <- function(ep,
      nrow(fn_map[fn_type == type]) == 0 |
      (type == "stat_across_strata_across_trt" & !any(ep_accepted[[grouping_cols[[1]]]] != "TOTAL_"))
      ){
-    return(data.table::data.table(SKIP_=TRUE))
+    return(data.table::data.table(SKIP_ = TRUE))
   }
 
   if (type %in% c("stat_by_strata_by_trt", "stat_by_strata_across_trt")) {
@@ -155,8 +156,8 @@ list_group_and_levels <- function(
     data,
     grouping_col
 ){
-  l = list(data[, unique(get(grouping_col))])
-  names(l) = grouping_col
+  l <- list(data[, unique(get(grouping_col))])
+  names(l) <- grouping_col
   return (l)
 }
 
@@ -169,6 +170,7 @@ list_group_and_levels <- function(
 #' @param ep A `data.table` containing endpoint data to be expanded.
 #' @param grouping_cols A character vector specifying the columns used for
 #'   grouping in the expansion.
+#' @param analysis_data_container data.table containing the analysis data.
 #' @param data_col The name of the column in `ep` that contains the ADaM
 #'   dataset.
 #' @param id_col The name of the column in `ep` that contains the unique
@@ -187,7 +189,7 @@ expand_ep_for_stats <- function(
     col_prefix
 ){
 
-  name_expand_col = paste(col_prefix, "expand_spec", sep="_")
+  name_expand_col <- paste(col_prefix, "expand_spec", sep="_")
 
   ep[,"_i_" := .I]
   setkey(ep, key_analysis_data)
@@ -214,7 +216,7 @@ expand_ep_for_stats <- function(
 
   ep_exp[,"_i_":= .I]
   ep_exp_with_data <- ep_exp[analysis_data_container, nomatch = NULL]
-  filter_col_name = paste(col_prefix, "filter", sep="_")
+  filter_col_name <- paste(col_prefix, "filter", sep="_")
   ep_exp_with_data[, cell_index := llist(create_flag(get(data_col)[[1]],
                                                      singletons = c(get(filter_col_name)[[1]]))),
                    by = "_i_"]
@@ -247,17 +249,17 @@ define_expansion_cell_from_data <- function(
     col_prefix
 ){
   if (is.character(grouping_cols)){
-    grouping_cols = c(grouping_cols)
+    grouping_cols <- c(grouping_cols)
   }
   stopifnot(all(grouping_cols %in% names(row)))
 
   # Get the actual grouping variables
-  grouping_col_values = row[, .SD, .SDcols=grouping_cols]
-  grouping_var_list = vector(mode="list", length(grouping_col_values))
-  names(grouping_var_list) = grouping_col_values
+  grouping_col_values <- row[, .SD, .SDcols=grouping_cols]
+  grouping_var_list <- vector(mode="list", length(grouping_col_values))
+  names(grouping_var_list) <- grouping_col_values
 
   if(row[["only_strata_with_events"]]){
-    dat <-  row[,get(data_col)][[1]][row[["event_index"]]]
+    dat <- row[,get(data_col)][[1]][row[["event_index"]]]
   }else{
     dat <- row[,get(data_col)][[1]]
   }
diff --git a/R/try_and_validate.R b/R/try_and_validate.R
index dbfb7e0..31956cd 100644
--- a/R/try_and_validate.R
+++ b/R/try_and_validate.R
@@ -14,18 +14,6 @@
 #'
 #' @return The result of the evaluated expression if successful and valid.
 #' @export
-
-
-
-#'
-#' @param expr_ Expression of type `call` to be wrapped
-#' @param debug_dir directory for debugging dump [/tmp]
-#' @param validator validation function, passthrough default.
-#' @param stage_debugging
-#'
-#' @return data.table::data.table
-#' @noRd
-#'
 try_and_validate <- function(expr_,
                              expr_name = NA_character_,
                              #TODO Allow forwarding of meaning full names.
@@ -35,7 +23,7 @@ try_and_validate <- function(expr_,
                              },
                              stage_debugging = TRUE) {
   # Capture expression information
-  expr_sub = substitute(expr_)
+  expr_sub <- substitute(expr_)
   if (!identical(class(expr_sub), "call")) {
     stop(sprintf(
       "Expr_(%s) must be of class `call`. Found: (%s)",
@@ -44,7 +32,7 @@ try_and_validate <- function(expr_,
     ))
   }
 
-  expr_list = as.list(expr_sub) # un evaluated call list
+  expr_list <- as.list(expr_sub) # un evaluated call list
   # Find the function definition in the calling env.
   if (rlang::is_call_simple(expr_sub)) {
     expr_fn <- get(expr_list[[1]], envir = parent.frame())
@@ -60,8 +48,7 @@ try_and_validate <- function(expr_,
     err_msg <- paste0("Failed to EVALUATE function with error:",
                       "\n ", expr_result[[1]])
 
-  } else if (!is.na(validator_err <-
-                    validator(expr_result))) {
+  } else if (!is.na(validator_err <- validator(expr_result))) {
     #validate output
     err_msg <-
       paste("Failed to VALIDATE function output with error:",
@@ -76,12 +63,11 @@ try_and_validate <- function(expr_,
 
   # Match arguments with formals if possible
   if (is.primitive(expr_fn)) {
-    expr_call_char = deparse(expr_sub)
-    expr_arg_list = expr_list[-1]
+    expr_call_char <- deparse(expr_sub)
+    expr_arg_list <- expr_list[-1]
   } else {
-    expr_matched = match.call(definition = expr_fn,
-                              call = expr_sub)
-    expr_call_char = deparse(expr_matched)
+    expr_matched <- match.call(definition = expr_fn, call = expr_sub)
+    expr_call_char <- deparse(expr_matched)
     expr_arg_list <- as.list(expr_matched)[-1]
   }
   # Find a name if unset.
@@ -103,16 +89,17 @@ try_and_validate <- function(expr_,
   debug_file <- stage_debug(
     fn_name = expr_name,
     fn = expr_fn,
-    arg_list = lapply(expr_arg_list, eval, envir = parent.frame()),
-    err_msg = full_error,
-    debug_dir = debug_dir
+    arg_list <- lapply(expr_arg_list, eval, envir = parent.frame()),
+    err_msg <- full_error,
+    debug_dir <- debug_dir
   )
 
   full_error <- paste(
     full_error,
     "---",
     sprintf(
-      "Debugging session created: Launch with:\n chef::load_debug_session('%s')",
+      "Debugging session created: Launch with:\n
+       chef::load_debug_session('%s')",
       debug_file
     ),
     "---",
@@ -152,8 +139,8 @@ stage_debug <-
     debug_env[["ns"]] <- search()
 
     dir.create(debug_dir, showWarnings = FALSE, recursive = FALSE)
-    norm_dir = normalizePath(debug_dir)
-    filepath = file.path(norm_dir, paste0(fn_name, ".Rdata"))
+    norm_dir <- normalizePath(debug_dir)
+    filepath <- file.path(norm_dir, paste0(fn_name, ".Rdata"))
 
     saveRDS(debug_env, file = filepath) #Set dynamically
 
@@ -177,20 +164,19 @@ load_debug_session <- function(debug_file) {
   # Get debug env.
   debug_env <- readRDS(debug_file)
   cli::cli_h1("Launching debug session for: {.val {debug_env$fn_name}}")
-  #message(paste0("Launching debug session for: ", debug_env$fn_name))
 
   cli::cli_h3("Original error msg:")
   cli::cli_par()
   cli::cli_verbatim(debug_env$err_msg)
-  cli::cli_text("──")
+  cli::cli_text("--")
   cli::cli_end()
-  #message(paste("Original error msg:", debug_env$err_msg, sep="\n" ))
-
 
   if (is.primitive(debug_env$fn)) {
     cli::cli_alert_danger(
-      "The inspected function ({.val {deparse(debug_env$fn)}}) is a primitive and cannot be inspected using debugonce.\
-      You can still load the debug environemnt and inspect inputs and function: readRDS({.path {debug_file}})",
+      "The inspected function ({.val {deparse(debug_env$fn)}}) is a 
+      primitive and cannot be inspected using debugonce.\
+      You can still load the debug environemnt and inspect 
+      inputs and function: readRDS({.path {debug_file}})",
       wrap = TRUE
     )
     cli::cli_alert_info("Debug session ended")
@@ -207,7 +193,8 @@ load_debug_session <- function(debug_file) {
 
   extra_libraries <- setdiff(debug_env$ns, search())
   if (length(extra_libraries) > 0) {
-    cli::cli_alert_warning("The following libraries was available at runtime but isn't currently.")
+    cli::cli_alert_warning("The following libraries was available at runtime 
+    but isn't currently.")
     cli::cli_li(extra_libraries)
   }
 
@@ -230,10 +217,10 @@ load_debug_session <- function(debug_file) {
 #'
 #' @return An error message if validation fails, otherwise NA.
 validate_crit_output <- function(output) {
-  if (!(isTRUE(output) |
-        isFALSE(output))) {
+  if (!(isTRUE(output) | isFALSE(output))) {
     paste(
-      "The return value from the endpoint criterion function must be a logical of length 1, i.e.",
+      "The return value from the endpoint criterion 
+      function must be a logical of length 1, i.e.",
       "TRUE or FALSE"
     )
   }
@@ -253,14 +240,15 @@ validate_crit_output <- function(output) {
 validate_stat_output <- function(output) {
   # if not a DT return early
   if (!data.table::is.data.table(output)) {
-    err_msg <- paste0("Expected (data.table::data.table) Found: ", class(output))
+    err_msg <- paste0("Expected (data.table::data.table). Found: ",
+                      class(output))
     return(err_msg)
   }
 
   # if DT check if compliant
   err_messages <- c()
-  expected_sorted = sort(c("label","description", "qualifiers", "value"))
-  actual_sorted   = sort(names(output))
+  expected_sorted <- sort(c("label", "description", "qualifiers", "value"))
+  actual_sorted <- sort(names(output))
   if (!identical(expected_sorted, actual_sorted)) {
     actual_diff <- setdiff(actual_sorted, expected_sorted)
     expected_diff <- setdiff(expected_sorted, actual_sorted)
diff --git a/R/use_chef.R b/R/use_chef.R
index 5ab0f1b..27e89b7 100644
--- a/R/use_chef.R
+++ b/R/use_chef.R
@@ -18,7 +18,7 @@
 #'   `mk_adam_*()` and criterion functions for example, and any other functions
 #'   that are used in the pipelines.
 #' @param pipeline_id Character sting. Alphanumeric only
-#' @param endpoint_def_fn If you would like to use an existing
+#' @param mk_endpoint_def_fn If you would like to use an existing
 #'   `mk_endpoint_def_*()` function as the starting point for the pipeline,
 #'   supply the unquoted function name here. This assumes there are no arguments
 #'   to the function call and the functions have to be available from the global
@@ -39,6 +39,8 @@
 #'   `my_criteria_fn`). The functions have to be available from the global
 #'   environment (i.e if you type `my_criteria_fn()` into the console, it would
 #'   find the function and try to run in).
+#' @param branch_group_size Numeric.
+#' @param env Environment.
 #'
 #' @return Nothing, run for side effects.
 #' @export
diff --git a/man/add_event_index.Rd b/man/add_event_index.Rd
index 816da4a..5a185cb 100644
--- a/man/add_event_index.Rd
+++ b/man/add_event_index.Rd
@@ -12,6 +12,8 @@ typically the output from \code{expand_over_endpoints}. It assumes the inclusion
 of the columns \code{pop_var}, \code{pop_value}, \code{period_var}, \code{period_value},
 \code{endpoint_filter}, \code{endpoint_group_filter}, and \code{custom_pop_filter}, which
 are used to define the conditions for event indexing.}
+
+\item{analysis_data_container}{A data.table containing the analysis data.}
 }
 \value{
 A \code{data.table} similar to the input but with an additional
diff --git a/man/add_forced_group_levels.Rd b/man/add_forced_group_levels.Rd
index 6227bd1..a64fb13 100644
--- a/man/add_forced_group_levels.Rd
+++ b/man/add_forced_group_levels.Rd
@@ -7,9 +7,9 @@
 add_forced_group_levels(combos_all, forced_group_levels)
 }
 \arguments{
-\item{combos_all}{A data.table containing all combinations of group levels found in the analysis data}
+\item{combos_all}{A data.table containing all combinations of group levels found in the analysis data.}
 
-\item{forced_group_levels}{A one column data.table containing a required set of group levels of a grouping variable}
+\item{forced_group_levels}{A one column data.table containing a required set of group levels of a grouping variable.}
 }
 \value{
 A data.table containing all combinations of group levels exapnded with the forced grouping levels.
diff --git a/man/add_id.Rd b/man/add_id.Rd
index 0634b71..9740c1c 100644
--- a/man/add_id.Rd
+++ b/man/add_id.Rd
@@ -7,7 +7,7 @@
 add_id(ep)
 }
 \arguments{
-\item{ep}{}
+\item{ep}{A \code{data.table} containing endpoint definitions.}
 }
 \value{
 data.table
diff --git a/man/apply_criterion_by_strata.Rd b/man/apply_criterion_by_strata.Rd
index 0b46b4c..91b56cc 100644
--- a/man/apply_criterion_by_strata.Rd
+++ b/man/apply_criterion_by_strata.Rd
@@ -15,6 +15,8 @@ apply_criterion_by_strata(
 \item{ep}{A \code{data.table} containing endpoint data with applied endpoint
 criteria, typically the output from \code{apply_criterion_endpoint}.}
 
+\item{analysis_data_container}{data.table containing the analysis data.}
+
 \item{fn_map}{A \code{data.table} mapping endpoint definitions to by-strata
 criteria functions.}
 
diff --git a/man/apply_criterion_endpoint.Rd b/man/apply_criterion_endpoint.Rd
index a770fcc..c76b5c0 100644
--- a/man/apply_criterion_endpoint.Rd
+++ b/man/apply_criterion_endpoint.Rd
@@ -10,6 +10,8 @@ apply_criterion_endpoint(ep, analysis_data_container, fn_map)
 \item{ep}{A \code{data.table} containing expanded endpoint definitions and
 associated data, typically the output from \code{add_event_index}.}
 
+\item{analysis_data_container}{data.table containing the analysis data.}
+
 \item{fn_map}{A \code{data.table} mapping endpoint definitions to criterion
 functions.}
 }
diff --git a/man/apply_stats.Rd b/man/apply_stats.Rd
index 064e24e..f9152fe 100644
--- a/man/apply_stats.Rd
+++ b/man/apply_stats.Rd
@@ -15,11 +15,11 @@ apply_stats(
 \item{ep}{A \code{data.table} containing prepared endpoint data for statistical
 analysis, typically the output from \code{prepare_for_stats}.}
 
+\item{analysis_data_container}{data.table containing the analysis data.
+functions.}
+
 \item{type}{The type of statistical function. Can be one of
 "stat_by_strata_by_trt", "stat_by_strata_across_trt", or "stat_across_strata_across_trt"}
-
-\item{fn_map}{A \code{data_table} mapping endpoint definitions to statistical
-functions.}
 }
 \value{
 A \code{data.table} with statistical results appended.
diff --git a/man/define_expanded_ep.Rd b/man/define_expanded_ep.Rd
index cced73c..a6e63cf 100644
--- a/man/define_expanded_ep.Rd
+++ b/man/define_expanded_ep.Rd
@@ -18,6 +18,9 @@ define_expanded_ep(
 each element corresponds to a variable used for grouping endpoints and
 contains the levels for that grouping variable.}
 
+\item{forced_group_levels}{data.table (optional). Table with group levels
+that must be included in the expansion, regardless of \code{group_by}.}
+
 \item{col_prefix}{A prefix used to create the names of the metadata and
 filter columns in the output \code{data.table}. Defaults to "endpoint_group".}
 }
diff --git a/man/expand_ep_for_stats.Rd b/man/expand_ep_for_stats.Rd
index ba4a653..b3a937c 100644
--- a/man/expand_ep_for_stats.Rd
+++ b/man/expand_ep_for_stats.Rd
@@ -19,6 +19,8 @@ expand_ep_for_stats(
 \item{grouping_cols}{A character vector specifying the columns used for
 grouping in the expansion.}
 
+\item{analysis_data_container}{data.table containing the analysis data.}
+
 \item{data_col}{The name of the column in \code{ep} that contains the ADaM
 dataset.}
 
diff --git a/man/expand_over_endpoints.Rd b/man/expand_over_endpoints.Rd
index eb4551a..b22bff4 100644
--- a/man/expand_over_endpoints.Rd
+++ b/man/expand_over_endpoints.Rd
@@ -10,6 +10,8 @@ expand_over_endpoints(ep, analysis_data_container)
 \item{ep}{A \code{data.table} containing endpoint definitions, where each row
 corresponds to a different endpoint and contains relevant attributes such
 as the endpoint name, type, and criteria.}
+
+\item{analysis_data_container}{data.table containing the analysis data.}
 }
 \value{
 A \code{data.table} where each row corresponds to an expanded endpoint
diff --git a/man/join_adam.Rd b/man/join_adam.Rd
deleted file mode 100644
index c034aac..0000000
--- a/man/join_adam.Rd
+++ /dev/null
@@ -1,28 +0,0 @@
-% Generated by roxygen2: do not edit by hand
-% Please edit documentation in R/mk_filtered_endpoint_dt.R
-\name{join_adam}
-\alias{join_adam}
-\title{Filter adam data}
-\usage{
-join_adam(
-  ep,
-  ep_fn_map,
-  adam_db,
-  filter_pop = TRUE,
-  filter_period = TRUE,
-  filter_trt = TRUE,
-  filter_user_defined = TRUE
-)
-}
-\arguments{
-\item{adam_db}{data.table. A table containing the adam datasets associated
-with each data_prepare}
-
-\item{ep_unnest}{data.table. An unnested endpoint definition table}
-}
-\value{
-a data.table with the filtered adam data.
-}
-\description{
-Filter adam data
-}
diff --git a/man/mk_endpoint_str.Rd b/man/mk_endpoint_str.Rd
index 3f42877..cfbee3e 100644
--- a/man/mk_endpoint_str.Rd
+++ b/man/mk_endpoint_str.Rd
@@ -35,6 +35,8 @@ mk_endpoint_str(
 
 \item{pop_value}{Character.}
 
+\item{custom_pop_filter}{Character.}
+
 \item{treatment_var}{Character.}
 
 \item{treatment_refval}{Character.}
@@ -57,6 +59,8 @@ mk_endpoint_str(
 
 \item{stat_by_strata_across_trt}{List.}
 
+\item{stat_across_strata_across_trt}{List.}
+
 \item{crit_endpoint}{List.}
 
 \item{crit_by_strata_by_trt}{List.}
@@ -64,6 +68,8 @@ mk_endpoint_str(
 \item{crit_by_strata_across_trt}{List.}
 
 \item{only_strata_with_events}{Boolean.}
+
+\item{env}{Environment.}
 }
 \value{
 A data.table containing the endpoint specification.
diff --git a/man/prepare_for_stats.Rd b/man/prepare_for_stats.Rd
index ec1aaad..f2b3730 100644
--- a/man/prepare_for_stats.Rd
+++ b/man/prepare_for_stats.Rd
@@ -18,6 +18,8 @@ prepare_for_stats(
 \item{ep}{A \code{data.table} containing expanded endpoint definitions and
 associated data, typically the output from \code{apply_criterion_by_strata}.}
 
+\item{analysis_data_container}{data.table containing the analysis data.}
+
 \item{fn_map}{A \code{data.table} mapping endpoint definitions to statistical
 functions.}
 
diff --git a/man/try_and_validate.Rd b/man/try_and_validate.Rd
new file mode 100644
index 0000000..13a40a7
--- /dev/null
+++ b/man/try_and_validate.Rd
@@ -0,0 +1,37 @@
+% Generated by roxygen2: do not edit by hand
+% Please edit documentation in R/try_and_validate.R
+\name{try_and_validate}
+\alias{try_and_validate}
+\title{Try and Validate Wrapper for Statistical Functions}
+\usage{
+try_and_validate(
+  expr_,
+  expr_name = NA_character_,
+  debug_dir = "debug",
+  validator = function(expr_result) {
+     NA_character_
+ },
+  stage_debugging = TRUE
+)
+}
+\arguments{
+\item{expr_}{The expression of type \code{call} to be evaluated, typically a call
+to a statistical function.}
+
+\item{expr_name}{The name of the expression, used for debugging purposes.}
+
+\item{debug_dir}{The directory where debugging information will be stored.}
+
+\item{validator}{A function used to validate the output of the expression.}
+
+\item{stage_debugging}{A flag indicating whether to stage debugging
+information in case of errors.}
+}
+\value{
+The result of the evaluated expression if successful and valid.
+}
+\description{
+Attempts to execute a statistical function and validates its
+output. If the function fails or the output is invalid, it provides
+meaningful error messages and sets up a debugging environment.
+}
diff --git a/man/use_chef.Rd b/man/use_chef.Rd
index b103509..326d0b4 100644
--- a/man/use_chef.Rd
+++ b/man/use_chef.Rd
@@ -29,6 +29,13 @@ that are used in the pipelines.}
 
 \item{pipeline_id}{Character sting. Alphanumeric only}
 
+\item{mk_endpoint_def_fn}{If you would like to use an existing
+\verb{mk_endpoint_def_*()} function as the starting point for the pipeline,
+supply the unquoted function name here. This assumes there are no arguments
+to the function call and the functions have to be available from the global
+enironment (i.e if you type \code{my_fun()} into the console, it would find the
+function and try to run in)}
+
 \item{mk_adam_fn}{List of functions used for making adam dataset. This is
 useful if you want to supply already existing functions. This must be a
 list, and each element must be an unquoted function name (e.g.
@@ -46,12 +53,9 @@ must be a list, and each element must be an unquoted function name (e.g.
 environment (i.e if you type \code{my_criteria_fn()} into the console, it would
 find the function and try to run in).}
 
-\item{endpoint_def_fn}{If you would like to use an existing
-\verb{mk_endpoint_def_*()} function as the starting point for the pipeline,
-supply the unquoted function name here. This assumes there are no arguments
-to the function call and the functions have to be available from the global
-enironment (i.e if you type \code{my_fun()} into the console, it would find the
-function and try to run in)}
+\item{branch_group_size}{Numeric.}
+
+\item{env}{Environment.}
 }
 \value{
 Nothing, run for side effects.
diff --git a/tests/testthat/test-targets.R b/tests/testthat/test-targets.R
index 2e988e3..ffb1173 100644
--- a/tests/testthat/test-targets.R
+++ b/tests/testthat/test-targets.R
@@ -156,7 +156,6 @@ test_that("branching after prepare for stats step works",
               branch_group_size = 1
 
             )
-
             dump("n_subev", file = "R/custom_functions.R")
             dump("n_sub", file = "R/custom_functions.R", append = TRUE)
 
@@ -168,7 +167,7 @@ test_that("branching after prepare for stats step works",
             expect_true(all(is.na(x$error)))
             tar_load(ep_stat)
             expect_equal(NROW(ep_stat), 12)
-            expect_equal(NCOL(ep_stat), 39)
+            expect_equal(NCOL(ep_stat), 37)
             expect_snapshot(ep_stat$stat_result_value)
 })
 
@@ -380,3 +379,101 @@ test_that("Only affected branches outdated when new strata added",
             })
 
           })
+
+
+test_that("Check for discordant columns in result data model when having one endpoint spec without grouping and one endpoint spec with grouping", {
+
+ # SETUP -------------------------------------------------------------------
+    mk_endpoint_def <- function() {
+        ep <- mk_endpoint_str(
+            study_metadata = list(),
+            pop_var = "SAFFL",
+            pop_value = "Y",
+            treatment_var = "TRT01A",
+            treatment_refval = "Xanomeline High Dose",
+            stratify_by = list(c("SEX", "AGEGR1")),
+            data_prepare = mk_adae,
+            endpoint_label = "A",
+            custom_pop_filter =
+                "TRT01A %in% c('Placebo', 'Xanomeline High Dose')",
+            group_by = list(list(
+                AESOC = c(), AESEV = c()
+            )),
+            stat_by_strata_by_trt = list(c(n_sub))
+        )
+
+        ep2 <- mk_endpoint_str(
+            data_prepare = mk_advs,
+            treatment_var = "TRT01A",
+            treatment_refval = "Xanomeline High Dose",
+            pop_var = "SAFFL",
+            pop_value = "Y",
+            stratify_by = list(c("AGEGR1", "SEX")),
+            stat_by_strata_by_trt = list(c(n_sub)),
+            endpoint_label = "Demographics endpoint (categorical measures)"
+        )
+
+        data.table::rbindlist(list(ep, ep2))
+    }
+
+    mk_advs <- function(study_metadata) {
+        # Read ADSL
+        adsl <- data.table::as.data.table(pharmaverseadam::adsl)
+
+        # Filter treatment arms
+        adsl <- adsl[adsl$TRT01A %in% c("Placebo", "Xanomeline High Dose")]
+        adsl[1, AGEGR1 := NA_character_]
+        adsl[2:10, SEX := NA_character_]
+
+        # Read ADVS
+        advs <- data.table::as.data.table(pharmaverseadam::advs)
+
+        # Identify baseline body weight
+        advs_bw <- advs[advs$PARAMCD == "WEIGHT" & advs$VISIT == "BASELINE"]
+
+        # Create new variable BW_BASELINE
+        advs_bw[["BW_BASELINE"]] <- advs_bw[["AVAL"]]
+
+        # Merge ADSL, ADAE and baseline body weight from ADVS
+        adam_out <-
+            merge(adsl, advs_bw[, c("BW_BASELINE", "USUBJID")], by = "USUBJID", all.x = TRUE)
+
+        return(adam_out)
+    }
+
+    # This is needed because mk_adcm it is calling from a new R session, it
+    # doesn't have access to the helper-* functions from chef
+    path <-
+        system.file("templates", package = "chef") |>
+        file.path("template-pipeline.R")
+    tmp <- readLines(path)
+    
+# ACT ---------------------------------------------------------------------
+    
+   tar_dir({
+        dir.create("R")
+        dump("n_sub", file = "R/custom_functions.R")
+        dump("mk_adae", file = "R/mk_adae.R")
+        dump("mk_advs", file = "R/mk_advs.R")
+        dump("mk_endpoint_def", file = "R/mk_endpoint_def.R")
+
+        x <- whisker::whisker.render(tmp, data = list(r_script_dir = "R/"))
+        writeLines(whisker::whisker.render(tmp, data = list(
+            r_script_dir = "R/")), con = "_targets.R")
+
+        tar_make()
+
+# EXPECT ------------------------------------------------------------------
+
+
+  targets::tar_load(ep_stat)
+  expect_equal(nrow(ep_stat), 700)
+  expect_equal(ncol(ep_stat), 37)
+  expect_equal(sum(ep_stat$endpoint_spec_id == 1), 690)
+  expect_equal(sum(ep_stat$endpoint_spec_id == 2), 10)
+
+  x <- tar_meta() |> data.table::setDT()
+  expect_false(any(!is.na(x$error)))
+
+    })
+})