Scans are basically Paintbars that have a Scan Result inside them.
When editing a paintbar in Simple mode, you would make it set the Scan Result option for one of the rules. You can set the scan result to any numeric or string value - that's the result that will show in portfolio for the scan. (A value of 0 is excluded - setting Scan Result to 0 is the same as having no Scan Result.
Using Advanced paintbar editor, you'd have more flexibility setting the Scan Result. This is done by calling the SetScanResult function - which can be passed the simple true parameter, a numeric parameter, or a string.