diff --git a/tests/DebugBar/Tests/DataCollector/AggregatedCollectorTest.php b/tests/DebugBar/Tests/DataCollector/AggregatedCollectorTest.php
index 51cb6e2..c485d63 100644
--- a/tests/DebugBar/Tests/DataCollector/AggregatedCollectorTest.php
+++ b/tests/DebugBar/Tests/DataCollector/AggregatedCollectorTest.php
@@ -19,7 +19,7 @@ class AggregatedCollectorTest extends DebugBarTestCase
         $this->c->addCollector($c = new MockCollector());
         $this->assertContains($c, $this->c->getCollectors());
         $this->assertEquals($c, $this->c['mock']);
-        $this->assertTrue(isset($this->c['mock']));
+        $this->assertArrayHasKey('mock', $this->c);
     }
 
     public function testCollect()
diff --git a/tests/DebugBar/Tests/DataCollector/TimeDataCollectorTest.php b/tests/DebugBar/Tests/DataCollector/TimeDataCollectorTest.php
index fc336e3..eb05c8a 100644
--- a/tests/DebugBar/Tests/DataCollector/TimeDataCollectorTest.php
+++ b/tests/DebugBar/Tests/DataCollector/TimeDataCollectorTest.php
@@ -37,7 +37,7 @@ class TimeDataCollectorTest extends DebugBarTestCase
         $this->assertEquals('bar', $m[0]['label']);
         $this->assertEquals('baz', $m[0]['collector']);
         $this->assertEquals(array('bar' => 'baz'), $m[0]['params']);
-        $this->assertTrue($m[0]['start'] < $m[0]['end']);
+        $this->assertLessThan($m[0]['end'], $m[0]['start']);
     }
 
     public function testCollect()
@@ -45,8 +45,8 @@ class TimeDataCollectorTest extends DebugBarTestCase
         $this->c->addMeasure('foo', 0, 10);
         $this->c->addMeasure('bar', 10, 20);
         $data = $this->c->collect();
-        $this->assertTrue($data['end'] > $this->s);
-        $this->assertTrue($data['duration'] > 0);
+        $this->assertGreaterThan($this->s, $data['end']);
+        $this->assertGreaterThan(0, $data['duration']);
         $this->assertCount(2, $data['measures']);
     }
 
@@ -59,7 +59,7 @@ class TimeDataCollectorTest extends DebugBarTestCase
         $m = $this->c->getMeasures();
         $this->assertCount(1, $m);
         $this->assertEquals('bar', $m[0]['label']);
-        $this->assertTrue($m[0]['start'] < $m[0]['end']);
+        $this->assertLessThan($m[0]['end'], $m[0]['start']);
         $this->assertSame('returnedValue', $returned);
     }
 }
diff --git a/tests/DebugBar/Tests/DebugBarTest.php b/tests/DebugBar/Tests/DebugBarTest.php
index a917f55..7bd152c 100644
--- a/tests/DebugBar/Tests/DebugBarTest.php
+++ b/tests/DebugBar/Tests/DebugBarTest.php
@@ -42,8 +42,8 @@ class DebugBarTest extends DebugBarTestCase
     {
         $this->debugbar->addCollector($c = new MockCollector());
         $this->assertEquals($c, $this->debugbar['mock']);
-        $this->assertTrue(isset($this->debugbar['mock']));
-        $this->assertFalse(isset($this->debugbar['foo']));
+        $this->assertArrayHasKey('mock', $this->debugbar);
+        $this->assertArrayNotHasKey('foo', $this->debugbar);
     }
 
     public function testStorage()
@@ -96,7 +96,7 @@ class DebugBarTest extends DebugBarTestCase
         $data = $this->debugbar->getStackedData();
         $this->assertArrayNotHasKey($ns, $http->session);
         $this->assertArrayHasKey($id, $data);
-        $this->assertEquals(1, count($data));
+        $this->assertCount(1, $data);
         $this->assertArrayHasKey('mock', $data[$id]);
         $this->assertEquals($c->collect(), $data[$id]['mock']);
     }
diff --git a/tests/DebugBar/Tests/DebugBarTestCase.php b/tests/DebugBar/Tests/DebugBarTestCase.php
index 6ab2d17..e61b5fd 100644
--- a/tests/DebugBar/Tests/DebugBarTestCase.php
+++ b/tests/DebugBar/Tests/DebugBarTestCase.php
@@ -19,13 +19,13 @@ abstract class DebugBarTestCase extends TestCase
     public function assertJsonIsArray($json)
     {
         $data = json_decode($json);
-        $this->assertTrue(is_array($data));
+        $this->assertIsArray($data);
     }
 
     public function assertJsonIsObject($json)
     {
         $data = json_decode($json);
-        $this->assertTrue(is_object($data));
+        $this->assertIsObject($data);
     }
 
     public function assertJsonArrayNotEmpty($json)