diff --git a/instat/clsRCodeStructure.vb b/instat/clsRCodeStructure.vb
index 032655868aa..29303529dd4 100644
--- a/instat/clsRCodeStructure.vb
+++ b/instat/clsRCodeStructure.vb
@@ -249,6 +249,7 @@ Public Class RCodeStructure
     ''' <param name="strDataFrameNames">            (Optional) Optional R character vector to give
     '''                                             names of new data frames if data frame list is
     '''                                             not named. </param>
+    ''' <param name="strAdjacentColumn">            (Optional) The new value for strAdjacentColumn. </param>
     '''--------------------------------------------------------------------------------------------
     Public Sub SetAssignTo(strTemp As String, Optional strTempDataframe As String = "", Optional strTempColumn As String = "", Optional strTempModel As String = "", Optional strTempGraph As String = "", Optional strTempSurv As String = "", Optional strTempTable As String = "", Optional bAssignToIsPrefix As Boolean = False, Optional bAssignToColumnWithoutNames As Boolean = False, Optional bInsertColumnBefore As Boolean = False, Optional bRequireCorrectLength As Boolean = True, Optional bDataFrameList As Boolean = False, Optional strDataFrameNames As String = "", Optional strAdjacentColumn As String = "")
         strAssignTo = strTemp
diff --git a/instat/clsRSyntax.vb b/instat/clsRSyntax.vb
index 2f590788fa3..b3492d3c162 100644
--- a/instat/clsRSyntax.vb
+++ b/instat/clsRSyntax.vb
@@ -214,8 +214,7 @@ Public Class RSyntax
     Public Sub SetAssignTo(strAssignToName As String, Optional strTempDataframe As String = "", Optional strTempColumn As String = "", Optional strTempModel As String = "", Optional strTempGraph As String = "", Optional bAssignToIsPrefix As Boolean = False, Optional bAssignToColumnWithoutNames As Boolean = False, Optional bInsertColumnBefore As Boolean = False, Optional bRequireCorrectLength As Boolean = True, Optional strAdjacentColumn As String = "")
         If bUseBaseOperator Then
             clsBaseOperator.SetAssignTo(strTemp:=strAssignToName, strTempDataframe:=strTempDataframe, strTempColumn:=strTempColumn, strTempModel:=strTempModel, strTempGraph:=strTempGraph, bAssignToIsPrefix:=bAssignToIsPrefix, bAssignToColumnWithoutNames:=bAssignToColumnWithoutNames, bInsertColumnBefore:=bInsertColumnBefore, bRequireCorrectLength:=bRequireCorrectLength, strAdjacentColumn:=strAdjacentColumn)
-        End If
-        If bUseBaseFunction Then 'TODO SJL 07/04/20 Use ElseIf?
+        ElseIf bUseBaseFunction Then
             clsBaseFunction.SetAssignTo(strAssignToName, strTempDataframe:=strTempDataframe, strTempColumn:=strTempColumn, strTempModel:=strTempModel, strTempGraph:=strTempGraph, bAssignToIsPrefix:=bAssignToIsPrefix, bAssignToColumnWithoutNames:=bAssignToColumnWithoutNames, bInsertColumnBefore:=bInsertColumnBefore, bRequireCorrectLength:=bRequireCorrectLength, strAdjacentColumn:=strAdjacentColumn)
         ElseIf bUseCommandString Then
             clsBaseCommandString.SetAssignTo(strAssignToName, strTempDataframe:=strTempDataframe, strTempColumn:=strTempColumn, strTempModel:=strTempModel, strTempGraph:=strTempGraph, bAssignToIsPrefix:=bAssignToIsPrefix, bAssignToColumnWithoutNames:=bAssignToColumnWithoutNames, bInsertColumnBefore:=bInsertColumnBefore, bRequireCorrectLength:=bRequireCorrectLength, strAdjacentColumn:=strAdjacentColumn)
diff --git a/instat/static/InstatObject/R/instat_object_R6.R b/instat/static/InstatObject/R/instat_object_R6.R
index 4d2ce61965a..1d1b4ddd5d7 100644
--- a/instat/static/InstatObject/R/instat_object_R6.R
+++ b/instat/static/InstatObject/R/instat_object_R6.R
@@ -479,8 +479,7 @@ DataBook$set("public", "set_metadata_changed", function(data_name = "", new_val)
 )
 
 DataBook$set("public", "add_columns_to_data", function(data_name, col_name = "", col_data, use_col_name_as_prefix = FALSE, hidden = FALSE, before, adjacent_column, num_cols, require_correct_length = TRUE, keep_existing_position = TRUE) {
-  if(missing(use_col_name_as_prefix)) self$get_data_objects(data_name)$add_columns_to_data(col_name, col_data, hidden = hidden, before = before, adjacent_column = adjacent_column, num_cols = num_cols, require_correct_length = require_correct_length, keep_existing_position = keep_existing_position)
-  else self$get_data_objects(data_name)$add_columns_to_data(col_name, col_data, use_col_name_as_prefix = use_col_name_as_prefix, hidden = hidden, before = before, adjacent_column = adjacent_column, num_cols = num_cols, require_correct_length = require_correct_length, keep_existing_position = keep_existing_position)
+  self$get_data_objects(data_name)$add_columns_to_data(col_name, col_data, use_col_name_as_prefix = use_col_name_as_prefix, hidden = hidden, before = before, adjacent_column = adjacent_column, num_cols = num_cols, require_correct_length = require_correct_length, keep_existing_position = keep_existing_position)
 }
 )