diff --git a/reference/outcontrol/functions/ob-implicit-flush.xml b/reference/outcontrol/functions/ob-implicit-flush.xml
index 38267f7ff5..1075ba7def 100644
--- a/reference/outcontrol/functions/ob-implicit-flush.xml
+++ b/reference/outcontrol/functions/ob-implicit-flush.xml
@@ -10,7 +10,7 @@
   &reftitle.description;
   <methodsynopsis>
    <type>void</type><methodname>ob_implicit_flush</methodname>
-   <methodparam choice="opt"><type>int</type><parameter>flag</parameter><initializer>true</initializer></methodparam>
+   <methodparam choice="opt"><type>int</type><parameter>flag</parameter><initializer>1</initializer></methodparam>
   </methodsynopsis>
   <para>
    <function>ob_implicit_flush</function> will turn implicit flushing on or