diff --git a/optuna_dashboard/_app.py b/optuna_dashboard/_app.py
index af9f3841..461da83d 100644
--- a/optuna_dashboard/_app.py
+++ b/optuna_dashboard/_app.py
@@ -159,6 +159,19 @@ def get_study_summary(storage: BaseStorage, study_id: int) -> Optional[StudySumm
     return None
 
 
+def create_new_study(
+    storage: BaseStorage, study_name: str, directions: List[StudyDirection]
+) -> int:
+    if version.parse(optuna_ver) >= version.Version("3.1.0.dev") and version.parse(
+        optuna_ver
+    ) != version.Version("3.1.0b0"):
+        study_id = storage.create_new_study(study_name, directions=directions)  # type: ignore
+    else:
+        study_id = storage.create_new_study(study_name)
+        storage.set_study_directions(study_id, directions)  # type: ignore
+    return study_id
+
+
 def get_trials(storage: BaseStorage, study_id: int, ttl_seconds: int = 10) -> List[FrozenTrial]:
     with trials_cache_lock:
         trials = trials_cache.get(study_id, None)
@@ -241,7 +254,10 @@ def create_app(storage: BaseStorage, debug: bool = False) -> Bottle:
     @json_api_view
     def create_study() -> BottleViewReturn:
         study_name = request.json.get("study_name", None)
-        directions = request.json.get("directions", [])
+        directions = [
+            StudyDirection.MAXIMIZE if d.lower() == "maximize" else StudyDirection.MINIMIZE
+            for d in request.json.get("directions", [])
+        ]
         if (
             study_name is None
             or len(directions) == 0
@@ -251,27 +267,7 @@ def create_app(storage: BaseStorage, debug: bool = False) -> Bottle:
             return {"reason": "You need to set study_name and direction"}
 
         try:
-            if version.parse(optuna_ver) >= version.Version("3.1.0.dev"):
-                study_id = storage.create_new_study(
-                    study_name,
-                    directions=[
-                        StudyDirection.MAXIMIZE
-                        if d.lower() == "maximize"
-                        else StudyDirection.MINIMIZE
-                        for d in directions
-                    ],
-                )  # type: ignore
-            else:
-                study_id = storage.create_new_study(study_name)
-                storage.set_study_directions(
-                    study_id,
-                    [
-                        StudyDirection.MAXIMIZE
-                        if d.lower() == "maximize"
-                        else StudyDirection.MINIMIZE
-                        for d in directions
-                    ],
-                )  # type: ignore
+            study_id = create_new_study(storage, study_name, directions)
         except DuplicatedStudyError:
             response.status = 400  # Bad request
             return {"reason": f"'{study_name}' already exists"}
diff --git a/python_tests/test_api.py b/python_tests/test_api.py
index 4f12a2e3..ceb8f60a 100644
--- a/python_tests/test_api.py
+++ b/python_tests/test_api.py
@@ -4,9 +4,8 @@ from unittest import TestCase
 import optuna
 from optuna import get_all_study_summaries
 from optuna.study import StudyDirection
-from optuna.version import __version__ as optuna_ver
 from optuna_dashboard._app import create_app
-from packaging import version
+from optuna_dashboard._app import create_new_study
 
 from .wsgi_client import send_request
 
@@ -19,17 +18,8 @@ def objective(trial: optuna.trial.Trial) -> float:
 class APITestCase(TestCase):
     def test_get_study_summaries(self) -> None:
         storage = optuna.storages.InMemoryStorage()
-
-        if version.parse(optuna_ver) >= version.Version("3.1.0.dev"):
-            storage.create_new_study(
-                study_name="foo1", directions=[StudyDirection.MINIMIZE]
-            )  # type: ignore
-            storage.create_new_study(
-                study_name="foo2", directions=[StudyDirection.MINIMIZE]
-            )  # type: ignore
-        else:
-            storage.create_new_study("foo1")
-            storage.create_new_study("foo2")
+        create_new_study(storage, "foo1", [StudyDirection.MINIMIZE])
+        create_new_study(storage, "foo2", [StudyDirection.MINIMIZE])
 
         app = create_app(storage)
         status, _, body = send_request(
@@ -138,12 +128,7 @@ class APITestCase(TestCase):
 
     def test_create_study_duplicated(self) -> None:
         storage = optuna.storages.InMemoryStorage()
-        if version.parse(optuna_ver) >= version.Version("3.1.0.dev"):
-            storage.create_new_study(
-                study_name="foo", directions=[StudyDirection.MINIMIZE]
-            )  # type: ignore
-        else:
-            storage.create_new_study("foo")
+        create_new_study(storage, "foo", [StudyDirection.MINIMIZE])
         self.assertEqual(len(get_all_study_summaries(storage)), 1)
 
         app = create_app(storage)
@@ -163,16 +148,8 @@ class APITestCase(TestCase):
 
     def test_delete_study(self) -> None:
         storage = optuna.storages.InMemoryStorage()
-        if version.parse(optuna_ver) >= version.Version("3.1.0.dev"):
-            storage.create_new_study(
-                study_name="foo1", directions=[StudyDirection.MINIMIZE]
-            )  # type: ignore
-            storage.create_new_study(
-                study_name="foo2", directions=[StudyDirection.MINIMIZE]
-            )  # type: ignore
-        else:
-            storage.create_new_study(study_name="foo1")
-            storage.create_new_study(study_name="foo2")
+        create_new_study(storage, "foo1", [StudyDirection.MINIMIZE])
+        create_new_study(storage, "foo2", [StudyDirection.MINIMIZE])
         self.assertEqual(len(get_all_study_summaries(storage)), 2)
 
         app = create_app(storage)