diff --git a/APSIM.POStats.Shared/Collector.cs b/APSIM.POStats.Shared/Collector.cs
index e26712a..122dd47 100644
--- a/APSIM.POStats.Shared/Collector.cs
+++ b/APSIM.POStats.Shared/Collector.cs
@@ -142,8 +142,25 @@ private static List<Table> GetTablesFromFile(string apsimxFileName)
                                     Data = new List<VariableData>()
                                 });
                             }
-                            var matchFields = GetMatchColumnNamesForTable(apsimxFileName, tableName)
-                                              .Where(f => f != "SimulationName");
+
+                            List<string> matchFields = new List<string>();
+                            IEnumerable<string> fields = ["field_match_one", "field_match_two", "field_match_three", "field_match_four"];
+                            using (SqliteCommand cmd = new SqliteCommand($"SELECT * FROM _PredictedObserved WHERE name = '{tableName}'", db))
+                            {
+                                using (SqliteDataReader reader = cmd.ExecuteReader())
+                                {
+                                    if (reader.HasRows)
+                                    {
+                                        reader.Read();
+                                        foreach(string field in fields)
+                                        {
+                                            string match = reader[field].ToString();
+                                            if (!string.IsNullOrEmpty(match) && match != "SimulationName")
+                                                matchFields.Add(match);
+                                        }
+                                    }
+                                }
+                            }
 
                             string selectSQL = $"SELECT * FROM {tableName}";
                             using (SqliteCommand cmd = new SqliteCommand(selectSQL, db))
@@ -227,34 +244,6 @@ private static Dictionary<long, string> GetSimulationNameIdPairs(SqliteConnectio
             return returnPairs;
         }
 
-        /// <summary>
-        /// Get the column names that were used to match the predicted/observed data in a table.
-        /// </summary>
-        /// <param name="apsimxFileName">The .apsimx file that contains the match column names.</param>
-        /// <param name="tableName">The name of the table.</param>
-        /// <returns></returns>
-        private static IEnumerable<string> GetMatchColumnNamesForTable(string apsimxFileName, string tableName)
-        {
-            var options = new JsonDocumentOptions { AllowTrailingCommas = true };
-            using (JsonDocument document = JsonDocument.Parse(File.ReadAllText(apsimxFileName), options))
-            {
-                var rootNode = new JsonProxyForModel(document.RootElement);
-                var predictedObservedModel = rootNode.ChildrenRecursively
-                                            .FirstOrDefault(child => child.Type == "PredictedObserved" &&
-                                                                     child.Name == tableName);
-                if (predictedObservedModel == null)
-                    throw new Exception($"Cannot find predicted observed table {tableName} in file {apsimxFileName}");
-
-                var matchElements = new List<string>()
-                {
-                    predictedObservedModel.GetPropertyValue("FieldNameUsedForMatch"),
-                    predictedObservedModel.GetPropertyValue("FieldName2UsedForMatch"),
-                    predictedObservedModel.GetPropertyValue("FieldName3UsedForMatch")
-                };
-                return matchElements.Where(element => element != null);
-            }
-        }
-
         /// <summary>
         /// Create a label for the current row of a SqliteDataReader
         /// </summary>
diff --git a/APSIM.POStats.Tests/CollectorTests.cs b/APSIM.POStats.Tests/CollectorTests.cs
index be9081c..4e3c06b 100644
--- a/APSIM.POStats.Tests/CollectorTests.cs
+++ b/APSIM.POStats.Tests/CollectorTests.cs
@@ -52,6 +52,10 @@ public void TearDown()
     [Test]
     public void TestEnsureNormalCollectorOperationWorks()
     {
+        SqliteUtilities.CreateTable(database, DataTableUtilities.FromCSV("_PredictedObserved",
+            "Name,field_match_one,field_match_two,field_match_three,field_match_four" + Environment.NewLine +
+            "PO1,Date,,," + Environment.NewLine
+            ));
         SqliteUtilities.CreateTable(database, DataTableUtilities.FromCSV("_Simulations",
             "ID,Name" + Environment.NewLine +
             " 1,Sim1" + Environment.NewLine
@@ -154,6 +158,11 @@ public void EnsureObservedStringColumnsAreIgnored()
     [Test]
     public void EnsureObservedStringValuesInRowsAreIgnored()
     {
+        SqliteUtilities.CreateTable(database, DataTableUtilities.FromCSV("_PredictedObserved",
+            "Name,field_match_one,field_match_two,field_match_three,field_match_four" + Environment.NewLine +
+            "PO1,Date,,," + Environment.NewLine
+            ));
+
         SqliteUtilities.CreateTable(database, DataTableUtilities.FromCSV("_Simulations",
             "ID,Name" + Environment.NewLine +
             " 1,Sim1" + Environment.NewLine
@@ -182,6 +191,11 @@ public void EnsureObservedStringValuesInRowsAreIgnored()
     [Test]
     public void EnsurePOTableNotUnderDataStoreIsFound()
     {
+        SqliteUtilities.CreateTable(database, DataTableUtilities.FromCSV("_PredictedObserved",
+            "Name,field_match_one,field_match_two,field_match_three,field_match_four" + Environment.NewLine +
+            "PO1,Date,,," + Environment.NewLine
+            ));
+
         SqliteUtilities.CreateTable(database, DataTableUtilities.FromCSV("_Simulations",
             "ID,Name" + Environment.NewLine +
             " 1,Sim1" + Environment.NewLine
@@ -208,6 +222,11 @@ public void EnsurePOTableNotUnderDataStoreIsFound()
     [Test]
     public void EnsureCollectorFindsIntegers()
     {
+        SqliteUtilities.CreateTable(database, DataTableUtilities.FromCSV("_PredictedObserved",
+            "Name,field_match_one,field_match_two,field_match_three,field_match_four" + Environment.NewLine +
+            "PO1,Date,,," + Environment.NewLine
+            ));
+
         SqliteUtilities.CreateTable(database, DataTableUtilities.FromCSV("_Simulations",
             "ID,Name" + Environment.NewLine +
             " 1,Sim1" + Environment.NewLine