diff --git a/include/caosdb/data_type.h b/include/caosdb/data_type.h
index ad5d35a92a1c1b468bfbfcca65e9b549c4f204de..1e4418f089a8af6d48d67d12170ccb9343f9d5aa 100644
--- a/include/caosdb/data_type.h
+++ b/include/caosdb/data_type.h
@@ -155,12 +155,26 @@ public:
   DataType(ProtoDataType *wrapped)
     : ProtoMessageWrapper<ProtoDataType>(wrapped) {}
   DataType() : ProtoMessageWrapper<ProtoDataType>() {}
-  DataType(AtomicDataType data_type) : DataType() {
-    this->wrapped->set_atomic_data_type(
-      static_cast<ProtoAtomicDataType>(data_type));
+  /**
+   * Create an AtomicDataType typed DataType.  For references, use the std::string constructor.
+   */
+  DataType(AtomicDataType data_type, bool list_type = false) : DataType() {
+    if (list_type) {
+      this->wrapped->mutable_list_data_type()->set_atomic_data_type
+        (static_cast<ProtoAtomicDataType>(data_type));
+    } else {
+      this->wrapped->set_atomic_data_type(static_cast<ProtoAtomicDataType>(data_type));
+    }
   }
-  DataType(const std::string &data_type) : DataType() {
-    this->wrapped->mutable_reference_data_type()->set_name(data_type);
+  /**
+   * Create a reference typed DataType.
+   */
+  DataType(const std::string &data_type, bool list_type = false) : DataType() {
+    if (list_type) {
+      this->wrapped->mutable_list_data_type()->mutable_reference_data_type()->set_name(data_type);
+    } else {
+      this->wrapped->mutable_reference_data_type()->set_name(data_type);
+    }
   }
   [[nodiscard]] inline auto IsAtomic() const noexcept -> bool {
     return this->wrapped->data_type_case() == DataTypeCase::kAtomicDataType;
diff --git a/test/test_data_type.cpp b/test/test_data_type.cpp
index 92a204228bcafe0e315ae6387e6964cdfdf3895d..9364074dc7070229b68d505334fcf8766ba2b6cb 100644
--- a/test/test_data_type.cpp
+++ b/test/test_data_type.cpp
@@ -22,9 +22,7 @@
 
 #include "caosdb/data_type.h"               // for DataType, AtomicDataType
 #include "caosdb/entity.h"                  // for Entity
-#include "caosdb/entity/v1alpha1/main.pb.h" // for AtomicDataType, DataType
 #include "caosdb/logging.h"                 // for CAOSDB_LOG_DEBUG
-#include "caosdb/protobuf_helper.h"         // for CAOSDB_DEBUG_...
 #include <boost/log/core/record.hpp>        // for record
 #include <boost/log/detail/attachable_sstream_buf.hpp> // for basic_ostring...
 #include <boost/log/sources/record_ostream.hpp>        // for operator<<
@@ -45,15 +43,15 @@ using ProtoAtomicDataType = caosdb::entity::v1alpha1::AtomicDataType;
 TEST(test_data_type, test_atomic) {
   ProtoDataType proto_data_type;
 
-  for (int i = 1; i < 6; i++) {
+  for (auto map_el : atomicdatatype_names) {
     Entity entity;
     entity.SetRole(Role::PROPERTY);
     // the different AtomicDataType are associated with integers
-    entity.SetDataType(static_cast<AtomicDataType>(i));
+    entity.SetDataType(map_el.first);
     EXPECT_TRUE(entity.GetDataType().IsAtomic());
-    EXPECT_EQ(entity.GetDataType().AsAtomic(), static_cast<AtomicDataType>(i));
+    EXPECT_EQ(entity.GetDataType().AsAtomic(), map_el.first);
 
-    proto_data_type.set_atomic_data_type(static_cast<ProtoAtomicDataType>(i));
+    proto_data_type.set_atomic_data_type(static_cast<ProtoAtomicDataType>(map_el.first));
     DataType data_type(&proto_data_type);
     entity.SetDataType(data_type);
 
@@ -61,7 +59,7 @@ TEST(test_data_type, test_atomic) {
     EXPECT_EQ(data_type.AsReference().GetName(), std::basic_string<char>(""));
     EXPECT_FALSE(data_type.IsList());
     EXPECT_TRUE(data_type.IsAtomic());
-    EXPECT_EQ(data_type.AsAtomic(), static_cast<AtomicDataType>(i));
+    EXPECT_EQ(data_type.AsAtomic(), map_el.first);
   }
 }
 
@@ -85,13 +83,8 @@ TEST(test_data_type, test_reference) {
 }
 
 TEST(test_data_type, test_list_of_atomic) {
-  ProtoDataType proto_data_type;
-  auto *proto_list_data_type = proto_data_type.mutable_list_data_type();
-
-  for (int i = 1; i < 6; i++) {
-    proto_list_data_type->set_atomic_data_type(
-      static_cast<ProtoAtomicDataType>(i));
-    DataType data_type(&proto_data_type);
+  for (auto map_el : atomicdatatype_names) {
+    DataType data_type(map_el.first, true);
 
     EXPECT_FALSE(data_type.IsReference());
     EXPECT_FALSE(data_type.IsAtomic());
@@ -101,17 +94,12 @@ TEST(test_data_type, test_list_of_atomic) {
               std::basic_string<char>(""));
     EXPECT_TRUE(list_data_type.IsListOfAtomic());
     EXPECT_FALSE(list_data_type.IsListOfReference());
-    EXPECT_EQ(list_data_type.GetAtomicDataType(),
-              static_cast<AtomicDataType>(i));
+    EXPECT_EQ(list_data_type.GetAtomicDataType(), map_el.first);
   }
 }
 
 TEST(test_data_type, test_list_of_reference) {
-  ProtoDataType proto_data_type;
-  auto *proto_list_data_type = proto_data_type.mutable_list_data_type();
-
-  proto_list_data_type->mutable_reference_data_type()->set_name("person");
-  DataType data_type(&proto_data_type);
+  auto data_type = DataType("person", true);
 
   EXPECT_FALSE(data_type.IsReference());
   EXPECT_FALSE(data_type.IsAtomic());