diff --git a/code/6_sMRI_quantification_stats.ipynb b/code/6_sMRI_quantification_stats.ipynb
index 06a746c9..04215d85 100644
--- a/code/6_sMRI_quantification_stats.ipynb
+++ b/code/6_sMRI_quantification_stats.ipynb
@@ -3193,7 +3193,13 @@
    "execution_count": null,
    "metadata": {},
    "outputs": [],
-   "source": []
+   "source": [
+    "subjects_info_withna = bids_layout.get(suffix=\"participants\", extension=\".tsv\")[0].get_df()\n",
+    "subjects_info = subjects_info_withna.copy()\n",
+    "subjects_info[\"age\"] = subjects_info_withna[\"age\"].fillna(subjects_info_withna[\"age\"].mean())\n",
+    "subjects_info[\"sex\"] = subjects_info_withna[\"sex\"].fillna(subjects_info_withna[\"sex\"].mode()[0])\n",
+    "subjects_info.loc[subjects_info.isnull().any(axis=1), :]"
+   ]
   },
   {
    "cell_type": "markdown",