diff --git a/tests/test_unit/test_filtering.py b/tests/test_unit/test_filtering.py
index 3c7cafae..11a3b9ea 100644
--- a/tests/test_unit/test_filtering.py
+++ b/tests/test_unit/test_filtering.py
@@ -10,10 +10,36 @@
     savgol_filter,
 )
 
+# Dataset fixtures
+valid_datasets_without_nans = [
+    "valid_poses_dataset",
+    "valid_bboxes_dataset",
+]
+valid_datasets_with_nans = [
+    f"{dataset}_with_nan" for dataset in valid_datasets_without_nans
+]
+all_valid_datasets = valid_datasets_without_nans + valid_datasets_with_nans
+
+
+# Expected number of nans in the position array per individual,
+# for each dataset
+expected_n_nans_in_position_per_indiv = {
+    "valid_poses_dataset": {0: 0, 1: 0},
+    # filtering should not introduce nans if input has no nans
+    "valid_bboxes_dataset": {0: 0, 1: 0},
+    # filtering should not introduce nans if input has no nans
+    "valid_poses_dataset_with_nan": {0: 7, 1: 0},
+    # individual with index 0 has 7 frames with nans in position after
+    # filtering individual with index 1 has no nans after filtering
+    "valid_bboxes_dataset_with_nan": {0: 7, 1: 0},
+    # individual with index 0 has 7 frames with nans in position after
+    # filtering individual with index 0 has no nans after filtering
+}
+
 
 @pytest.mark.parametrize(
     "valid_dataset_with_nan",
-    ["valid_poses_dataset_with_nan", "valid_bboxes_dataset_with_nan"],
+    valid_datasets_with_nans,
 )
 @pytest.mark.parametrize(
     "max_gap, expected_n_nans_in_position", [(None, 0), (0, 3), (1, 2), (2, 0)]
@@ -106,12 +132,7 @@ def test_filter_by_confidence_on_position(
 
 @pytest.mark.parametrize(
     "valid_dataset",
-    [
-        "valid_poses_dataset",
-        "valid_bboxes_dataset",
-        "valid_poses_dataset_with_nan",
-        "valid_bboxes_dataset_with_nan",
-    ],
+    all_valid_datasets,
 )
 @pytest.mark.parametrize("window_size", [2, 4])
 def test_median_filter_on_position(valid_dataset, window_size, request):
@@ -134,30 +155,7 @@ def test_median_filter_on_position(valid_dataset, window_size, request):
 
 @pytest.mark.parametrize(
     ("valid_dataset, expected_n_nans_in_position_per_indiv"),
-    [
-        (
-            "valid_poses_dataset",
-            {0: 0, 1: 0},
-        ),  # median filtering should not introduce nans if input has no nans
-        (
-            "valid_bboxes_dataset",
-            {0: 0, 1: 0},
-        ),  # median filtering should not introduce nans if input has no nans
-        (
-            "valid_poses_dataset_with_nan",
-            {0: 7, 1: 0},
-        ),
-        # individual with index 0 has 7 frames with nans in position after
-        # filtering
-        # individual with index 1 has no nans after filtering
-        (
-            "valid_bboxes_dataset_with_nan",
-            {0: 7, 1: 0},
-        ),
-        # individual with index 0 has 7 frames with nans in position after
-        # filtering
-        # individual with index 0 has no nans after filtering
-    ],
+    [(k, v) for k, v in expected_n_nans_in_position_per_indiv.items()],
 )
 def test_median_filter_with_nans_on_position(
     valid_dataset,
@@ -203,12 +201,7 @@ def test_median_filter_with_nans_on_position(
 
 @pytest.mark.parametrize(
     "valid_dataset",
-    [
-        "valid_poses_dataset",
-        "valid_bboxes_dataset",
-        "valid_poses_dataset_with_nan",
-        "valid_bboxes_dataset_with_nan",
-    ],
+    all_valid_datasets,
 )
 @pytest.mark.parametrize("window, polyorder", [(2, 1), (4, 2)])
 def test_savgol_filter_on_position(valid_dataset, window, polyorder, request):
@@ -233,30 +226,7 @@ def test_savgol_filter_on_position(valid_dataset, window, polyorder, request):
 
 @pytest.mark.parametrize(
     ("valid_dataset, expected_n_nans_in_position_per_indiv"),
-    [
-        (
-            "valid_poses_dataset",
-            {0: 0, 1: 0},
-        ),  # median filtering should not introduce nans if input has no nans
-        (
-            "valid_bboxes_dataset",
-            {0: 0, 1: 0},
-        ),  # median filtering should not introduce nans if input has no nans
-        (
-            "valid_poses_dataset_with_nan",
-            {0: 7, 1: 0},
-        ),
-        # individual with index 0 has 7 frames with nans in position after
-        # filtering
-        # individual with index 1 has no nans after filtering
-        (
-            "valid_bboxes_dataset_with_nan",
-            {0: 7, 1: 0},
-        ),
-        # individual with index 0 has 7 frames with nans in position after
-        # filtering
-        # individual with index 0 has no nans after filtering
-    ],
+    [(k, v) for k, v in expected_n_nans_in_position_per_indiv.items()],
 )
 def test_savgol_filter_with_nans_on_position(
     valid_dataset, expected_n_nans_in_position_per_indiv, helpers, request
@@ -301,12 +271,7 @@ def test_savgol_filter_with_nans_on_position(
 
 @pytest.mark.parametrize(
     "valid_dataset",
-    [
-        "valid_poses_dataset",
-        "valid_bboxes_dataset",
-        "valid_poses_dataset_with_nan",
-        "valid_bboxes_dataset_with_nan",
-    ],
+    all_valid_datasets,
 )
 @pytest.mark.parametrize(
     "override_kwargs",