Consideration of the aims, data, method and sampling should have led the researcher to choose a suitable data collection method. Ongoing management of this process is important.

• Is the data collection strategy providing the desired numbers of respondents?
• Are all rail passengers from the population effectively represented by the responses? Are there other, previously unseen issues which chould be addressed by changing the collection approach?
• If the method is qualitative, for example, some analysis of the data might indicate aspects which require further exploration.