What is the best practice for outputting a variable which may or may not contain anything in PHP?

<?php
if ( ! $new_item) {
    $variable = 'Example';
}
?>
<form>
    <input type="text" name="inputbox" value="<?php echo @$variable; ?>" />
</form>

<?php echo ((isset($value) && $value != '') ? $value : 'Default'); ?>

function useDefault($value, $default = '')
{
    if (isset($value) && $value != '')
    {
        return $value;
    }
    else
    {
        return $default;
    }
}

<?php echo useDefault($value, 'default value'); ?>

$variable = (isset($new_item) && $new_item) ? 'Example' : 'Default Value';

if ( ! $new_item) {
    $variable = 'Example';
} else {
    $variable = 'Default value';
    //or
    $variable = '';
}

class example {
    public $somefield = 'default value';
}

$record = mysql_fetch_object($result, 'example');

$record = new example();

<form>
    <input type="text" name="somefield" value="<?php echo htmlspecialchars($record->somefield); ?>" />
</form>