if (strlen(trim($fields['page_number'])) == 0 || (is_numeric($fields['page_number']) && $fields['page_number'] < 1)) {
                if ($fields['paginate_results'] === 'yes') {
                    $this->_errors['page_number'] = __('A page number must be set');
                }
            } elseif (!self::__isValidPageString($fields['page_number'])) {