In early July I reported a crime to the local police. It wasn’t an emergency so I just used the number for the local station. Today I received a call from a research company acting on behalf of the police force, asking me to rate my experience of reporting the crime.
My first problem was that I struggled to remember it. I remembered the crime and ringing the police, but couldn’t remember when it was or any of the details of the call because it was so long ago (nearly two months in fact). The only reason I can tell you here that it was early July was because the questioner reminded me. This leads me to rule number one of follow-up research: make the follow-up call within a few days of the completed transaction; certainly don’t leave it two months.
Sometimes you want to wait a while for the respondent to have a chance to use or assess something, for example you might reasonably ask a respondent about the build quality of a product after a couple of months. But in this case I was being asked to rate the call and the quality of the service I received, something which was over and done. I should have received this call a few days after I called.