diff --git a/src/features/phone_esm/straw/process_user_event_related_segments.py b/src/features/phone_esm/straw/process_user_event_related_segments.py
index 1966ce64..4bf5ff90 100644
--- a/src/features/phone_esm/straw/process_user_event_related_segments.py
+++ b/src/features/phone_esm/straw/process_user_event_related_segments.py
@@ -54,6 +54,7 @@ def extract_ers_from_file(esm_df, device_id): # TODO: session_id groupby -> spre
     extracted_ers["label"] = "straw_event_" + snakemake.params["pid"] + "_" + extracted_ers.index.astype(str).str.zfill(3)
     extracted_ers["event_timestamp"] = esm_df.groupby("esm_session")['timestamp'].min().reset_index()['timestamp']
     extracted_ers["length"] = (extracted_ers["timestamp"] + time_before_questionnaire).apply(lambda x: format_timestamp(x))
+    # TODO: Think about adding questionnaire duration.
     extracted_ers["shift"] = time_before_questionnaire
     extracted_ers["shift"] = extracted_ers["shift"].apply(lambda x: format_timestamp(x))
     extracted_ers["shift_direction"] = -1