diff --git a/src/core/callback-trace-source.cc b/src/core/callback-trace-source.cc
index 7bcb41fe0..aa686c14d 100644
--- a/src/core/callback-trace-source.cc
+++ b/src/core/callback-trace-source.cc
@@ -55,7 +55,7 @@ CallbackTraceSourceTest::CbTwo (TraceContext const &context, uint8_t a, double b
 bool 
 CallbackTraceSourceTest::RunTests (void)
 {
-  bool ok = true;
+  bool result = true;
   TraceContext ctx;
 
   CallbackTraceSource<uint8_t,double> trace;
@@ -64,28 +64,31 @@ CallbackTraceSourceTest::RunTests (void)
   m_one = false;
   m_two = false;
   trace (1, 2);
-  if (!m_one || !m_two)
-    {
-      ok = false;
-    }
+  NS_TEST_ASSERT (m_one);
+  NS_TEST_ASSERT (m_two);
+
   trace.RemoveCallback (MakeCallback (&CallbackTraceSourceTest::CbOne, this));
   m_one = false;
   m_two = false;
   trace (1, 2);
-  if (m_one || !m_two)
-    {
-      ok = false;
-    }
+  NS_TEST_ASSERT (!m_one);
+  NS_TEST_ASSERT (m_two);
   trace.RemoveCallback (MakeCallback (&CallbackTraceSourceTest::CbTwo, this));
   m_one = false;
   m_two = false;
   trace (1, 2);
-  if (m_one || m_two)
-    {
-      ok = false;
-    }
+  NS_TEST_ASSERT (!m_one);
+  NS_TEST_ASSERT (!m_two);
 
-  return ok;
+  trace.AddCallback (MakeCallback (&CallbackTraceSourceTest::CbOne, this), ctx);
+  trace.AddCallback (MakeCallback (&CallbackTraceSourceTest::CbTwo, this), ctx);
+  m_one = false;
+  m_two = false;
+  trace (1, 2);
+  NS_TEST_ASSERT (m_one);
+  NS_TEST_ASSERT (m_two);
+
+  return result;
 }
 
 CallbackTraceSourceTest g_callbackTraceTest;