diff --git a/src/main.py b/src/main.py
index 25791df..b4cfb91 100644
--- a/src/main.py
+++ b/src/main.py
@@ -25,41 +25,41 @@ class MedTrackerApp:
         input_frame = ttk.LabelFrame(main_frame, text="New Entry")
         input_frame.grid(row=0, column=0, padx=10, pady=10, sticky="ew")
 
-        ttk.Label(input_frame, text="Depression (1-10):").grid(
+        ttk.Label(input_frame, text="Depression (0-10):").grid(
             row=0, column=0, sticky="w", padx=5, pady=2
         )
         self.depression_var = tk.IntVar()
         ttk.Scale(
             input_frame,
-            from_=1,
+            from_=0,
             to=10,
             orient=tk.HORIZONTAL,
             variable=self.depression_var,
         ).grid(row=0, column=1, sticky="ew")
 
-        ttk.Label(input_frame, text="Anxiety (1-10):").grid(
+        ttk.Label(input_frame, text="Anxiety (0-10):").grid(
             row=1, column=0, sticky="w", padx=5, pady=2
         )
         self.anxiety_var = tk.IntVar()
         ttk.Scale(
-            input_frame, from_=1, to=10, orient=tk.HORIZONTAL, variable=self.anxiety_var
+            input_frame, from_=0, to=10, orient=tk.HORIZONTAL, variable=self.anxiety_var
         ).grid(row=1, column=1, sticky="ew")
 
-        ttk.Label(input_frame, text="Sleep Quality (1-10):").grid(
+        ttk.Label(input_frame, text="Sleep Quality (0-10):").grid(
             row=2, column=0, sticky="w", padx=5, pady=2
         )
         self.sleep_var = tk.IntVar()
         ttk.Scale(
-            input_frame, from_=1, to=10, orient=tk.HORIZONTAL, variable=self.sleep_var
+            input_frame, from_=0, to=10, orient=tk.HORIZONTAL, variable=self.sleep_var
         ).grid(row=2, column=1, sticky="ew")
 
-        ttk.Label(input_frame, text="Appetite (1-10):").grid(
+        ttk.Label(input_frame, text="Appetite (0-10):").grid(
             row=3, column=0, sticky="w", padx=5, pady=2
         )
         self.appetite_var = tk.IntVar()
         ttk.Scale(
             input_frame,
-            from_=1,
+            from_=0,
             to=10,
             orient=tk.HORIZONTAL,
             variable=self.appetite_var,
@@ -121,14 +121,14 @@ class MedTrackerApp:
 
         self.load_data()
 
-    def on_double_click(self, event):
+    def on_double_click(self, event) -> None:
         """Handle double-click event to edit an entry."""
         if len(self.tree.get_children()) > 0:
             item_id = self.tree.selection()[0]
             item_values = self.tree.item(item_id, "values")
             self.create_edit_window(item_id, item_values)
 
-    def create_edit_window(self, item_id, values):
+    def create_edit_window(self, item_id, values) -> None:
         """Create a new Toplevel window for editing an entry."""
         edit_win = tk.Toplevel(self.root)
         edit_win.title("Edit Entry")
@@ -200,8 +200,12 @@ class MedTrackerApp:
         cancel_btn = ttk.Button(edit_win, text="Cancel", command=edit_win.destroy)
         cancel_btn.grid(row=6, column=1, padx=5, pady=10)
 
-    def save_edit(self, edit_win, timestamp, dep, anx, slp, app, note):
-        """Save the edited data to the CSV file."""
+    def save_edit(
+        self, edit_win, timestamp, dep: int, anx: int, slp: int, app: int, note: str
+    ) -> None:
+        """
+        Save the edited data to the CSV file.
+        """
         df = pd.read_csv(self.filename)
         # Find the row to update using the timestamp as a unique identifier
         df.loc[
@@ -215,12 +219,12 @@ class MedTrackerApp:
         messagebox.showinfo("Success", "Entry updated successfully!")
         self.load_data()
 
-    def on_closing(self):
+    def on_closing(self) -> None:
         if messagebox.askokcancel("Quit", "Do you want to quit the application?"):
             plt.close(self.fig)
             self.root.destroy()
 
-    def initialize_csv(self):
+    def initialize_csv(self) -> None:
         if not os.path.exists(self.filename):
             with open(self.filename, mode="w", newline="") as file:
                 writer = csv.writer(file)
@@ -228,7 +232,7 @@ class MedTrackerApp:
                     ["timestamp", "depression", "anxiety", "sleep", "appetite", "note"]
                 )
 
-    def add_entry(self):
+    def add_entry(self) -> None:
         timestamp = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
         with open(self.filename, mode="a", newline="") as file:
             writer = csv.writer(file)
@@ -247,14 +251,14 @@ class MedTrackerApp:
         self.clear_entries()
         self.load_data()
 
-    def clear_entries(self):
+    def clear_entries(self) -> None:
         self.depression_var.set(0)
         self.anxiety_var.set(0)
         self.sleep_var.set(0)
         self.appetite_var.set(0)
         self.note_var.set("")
 
-    def load_data(self):
+    def load_data(self) -> None:
         for i in self.tree.get_children():
             self.tree.delete(i)
 
@@ -269,7 +273,7 @@ class MedTrackerApp:
             except pd.errors.EmptyDataError:
                 self.update_graph(pd.DataFrame())
 
-    def update_graph(self, df):
+    def update_graph(self, df: pd.DataFrame) -> None:
         self.ax.clear()
         if not df.empty:
             df["timestamp"] = pd.to_datetime(df["timestamp"])