diff --git a/synapse/handlers/stats.py b/synapse/handlers/stats.py

index 3fd89af2a4..47f2e2a0c1 100644
--- a/synapse/handlers/stats.py
+++ b/synapse/handlers/stats.py
@@ -18,7 +18,7 @@ from typing import TYPE_CHECKING, Any, Dict, Iterable, Optional, Tuple
 
 from typing_extensions import Counter as CounterType
 
-from synapse.api.constants import EventTypes, Membership
+from synapse.api.constants import EventContentFields, EventTypes, Membership
 from synapse.metrics import event_processing_positions
 from synapse.metrics.background_process_metrics import run_as_background_process
 from synapse.types import JsonDict
@@ -254,7 +254,7 @@ class StatsHandler:
 
             elif typ == EventTypes.Create:
                 room_state["is_federatable"] = (
-                    event_content.get("m.federate", True) is True
+                    event_content.get(EventContentFields.FEDERATE, True) is True
                 )
             elif typ == EventTypes.JoinRules:
                 room_state["join_rules"] = event_content.get("join_rule")
@@ -273,7 +273,9 @@ class StatsHandler:
             elif typ == EventTypes.CanonicalAlias:
                 room_state["canonical_alias"] = event_content.get("alias")
             elif typ == EventTypes.GuestAccess:
-                room_state["guest_access"] = event_content.get("guest_access")
+                room_state["guest_access"] = event_content.get(
+                    EventContentFields.GUEST_ACCESS
+                )
 
         for room_id, state in room_to_state_updates.items():
             logger.debug("Updating room_stats_state for %s: %s", room_id, state)