diff --git a/src/Server/Transport/Sse/StreamTransport.php b/src/Server/Transport/Sse/StreamTransport.php
index ff5626f..d264c19 100644
--- a/src/Server/Transport/Sse/StreamTransport.php
+++ b/src/Server/Transport/Sse/StreamTransport.php
@@ -47,7 +47,7 @@ private function flushEvent(string $event, string $data): void
         echo sprintf('event: %s', $event).PHP_EOL;
         echo sprintf('data: %s', $data).PHP_EOL;
         echo PHP_EOL;
-        if (ob_get_length() !== false) {
+        if (false !== ob_get_length()) {
             ob_flush();
         }
         flush();