diff --git a/saqc/funcs/spikes_detection.py b/saqc/funcs/spikes_detection.py
index 198b711788c823f0626efe30a6d1590c78bebcde..072c480cbc9e5288658f97a5a2921cbdd31d044a 100644
--- a/saqc/funcs/spikes_detection.py
+++ b/saqc/funcs/spikes_detection.py
@@ -177,7 +177,7 @@ def spikes_flagMultivarScores(data, field, flagger, fields, trafo=np.log, alpha=
 
     # data fransformation/extraction
     val_frame = data[fields]
-    val_frame = data.loc[data.index_of('shared')].to_df()
+    val_frame = val_frame.loc[val_frame.index_of('shared')].to_df()
     val_frame.dropna(inplace=True)
     val_frame = val_frame.apply(trafo)