This approach isn't necessary for every goal but it seems to work well for many.
Firstly it does not diminish any of the standard SMART goal principles. Once you have a goal, identify the role that you and others play. Put the role through your identity filter and see if it matches your purpose and then your core values.
This might mean re-framing your role into something else. Recently a person I know was struggling with being called a real-estate agent and this didn't sit well with her core values. Fortunately someone was able to re-frame her role as property strategist. This is solving a particular investment solution rather than just selling and this sits better with her.
In terms of measurability of a goal it is important for the value based goal to fit within the boundaries of the organisation. Let me give you a business example. I have worked for a company that is owned by one or more parent companies. Our biggest customers are our parent companies themselves so delivering a profit is not always the best outcome for them. In their case delivering cost savings in their operation is more valuable than the subsidiary's profit. So the purpose of the subsidiary company in respect of the parent organisations is not profit oriented and that is reflected when setting and measuring outcomes.
For personal goals, non-attachment means that if things start going poorly or unexpected then alternatives can be arranged. Another way of saying this is don't count your chickens before they hatch.