public function array_filter($inputArray, $model)
    {
        $outputArray = array();
        foreach ($inputArray as $key => $value) {
            // Null and empty string are skipped
            if (is_null($value) || $value === '') {
                continue;
            }
            // Maybe do a check on multiOptions for checkboxes etc. to disable some 0 values $model->get($key, 'multiOptions');
            if ($value == '0' && $options = $model->get($key, 'multiOptions')) {
                if (count($options) == 2) {
                    // Probably a checkbox (multi flexi in limesurvey)
                    continue;
                }
            }
            $outputArray[$key] = $value;
        }
        return $outputArray;
    }