Augmenting conjoint results with additional data

It can be risky to make important marketing decisions based on a single research method or approach. It is the case that the development of many different types of new products occurs in pre-launch stages (sometimes in what's called a "Stage Gate" process) that involve testing and revising assumptions along the way. (Or they should.) So, for example, DCE/CBC studies are preceeded by initial secondary research, and by both qualitative and quantitative primary research. (Primary research is when you gather new data from customers.) They are often followed by forecasting and by other forms of concept testing, media testing, and so on.

(Here's the question) Aside from often being an important part of new product development, the information value of DCE/CBC studies themselves can sometimes be increased by augmenting them with additional data.   In what ways do you think this can be done?

Additional data might be data collected in the same survey, or data obtained in other ways. By "information value" I mean the extent to which the results support the best possible marketing decisions and enable important managerial insights.