diff --git a/mofax/core.py b/mofax/core.py
index d33452d..787f067 100644
--- a/mofax/core.py
+++ b/mofax/core.py
@@ -1330,9 +1330,9 @@ def get_sample_r2(
         views: Optional[Union[str, int, List[str], List[int]]] = None,
         df: bool = True,
     ) -> pd.DataFrame:
-        findices, factors = self.__check_factors(factors, unique=True)
-        groups = self.__check_groups(groups)
-        views = self.__check_views(views)
+        findices, factors = self._check_factors(factors, unique=True)
+        groups = self._check_groups(groups)
+        views = self._check_views(views)
 
         r2s = []
         for view in views:
diff --git a/mofax/utils.py b/mofax/utils.py
index 9587335..f38c619 100644
--- a/mofax/utils.py
+++ b/mofax/utils.py
@@ -17,6 +17,7 @@ def _load_samples_metadata(model):
         ],
         columns=["sample", "group"],
     )
+
     if "samples_metadata" in model.model:
         if len(list(model.model["samples_metadata"][model.groups[0]].keys())) > 0:
             _samples_metadata = pd.concat(
@@ -41,23 +42,36 @@ def _load_samples_metadata(model):
             if "sample" in _samples_metadata.columns:
                 del _samples_metadata["sample"]
 
-            samples_metadata = pd.concat(
-                [
-                    samples_metadata.reset_index(drop=True),
-                    _samples_metadata.reset_index(drop=True),
-                ],
-                axis=1,
-            )
-
             # Decode objects as UTF-8 strings
-            for column in samples_metadata.columns:
-                if samples_metadata[column].dtype == "object":
-                    try:
-                        samples_metadata[column] = [
-                            i.decode() for i in samples_metadata[column].values
-                        ]
-                    except (UnicodeDecodeError, AttributeError):
-                        pass
+            for df in [samples_metadata, _samples_metadata]:
+                for column in df.columns:
+                    if df[column].dtype == "object":
+                        try:
+                            df[column] = [i.decode() for i in df[column].values]
+                        except (UnicodeDecodeError, AttributeError):
+                            pass
+
+            if "sample" in _samples_metadata.columns:
+
+                samples_metadata = pd.merge(
+                    left=samples_metadata,
+                    left_on="sample",
+                    right=_samples_metadata,
+                    right_on="index",
+                )
+
+                if "index" in samples_metadata.columns:
+                    del samples_metadata["index"]
+
+            else:
+
+                samples_metadata = pd.concat(
+                    [
+                        samples_metadata.reset_index(drop=True),
+                        _samples_metadata.reset_index(drop=True),
+                    ],
+                    axis=1,
+                )
 
     samples_metadata = samples_metadata.set_index("sample")
     return samples_metadata
@@ -230,7 +244,7 @@ def _make_iterable(x):
 
 def calculate_r2(Z, W, Y):
     a = np.nansum((Y - Z.T.dot(W)) ** 2.0)
-    b = np.nansum(Y ** 2)
+    b = np.nansum(Y**2)
     r2 = (1.0 - a / b) * 100
     return r2