diff --git a/app.py b/app.py
index 7f088de..e79a3b2 100644
--- a/app.py
+++ b/app.py
@@ -540,16 +540,17 @@
         index=1  # デフォルトは「なし」
     )
 
-    # Q2: Confidence (横並び)
+    # Q2: Confidence (スライダー)
     container.markdown("**Q2: 確信度**")
-    confidence = container.radio(
+    confidence = container.slider(
         "確信度",
-        CONFIDENCE_OPTIONS,
-        index=3,  # 50%
-        format_func=lambda x: f"{x}%",
+        min_value=MIN_CONFIDENCE,
+        max_value=MAX_CONFIDENCE,
+        value=DEFAULT_CONFIDENCE,
+        step=1,
+        format="%d%%",
         key=f"confidence_{case_id}",
-        label_visibility="collapsed",
-        horizontal=True  # 変更: 横並び
+        label_visibility="collapsed"
     )
 
     # Q3: Reasons