ABSTRACT
It might not be clear how you could use this information, nor why it would be useful, but here’s how it would work. Say you wanted to do a study evaluating whether men were making use of an extended surgery service at a local doctor’s (since evidence suggests men do not use GPs much during the day). You want to interview men aged 30 to 50 to see whether they would be interested in such a surgery. The GP gives you a list of all patients who fit your search criteria, and you create a database. But it may not be correct, so having extra details may help. P. Jones doesn’t tell you whether a person is male or female, so knowing that this person is male means they can be invited to be in your study. Also, having a name, gender and address means you can now write to Mr P. Jones to tell him about your study. You can tell by the date of birth he fits the criteria for the work. The only problem is that Mr Jones doesn’t appear to be on the telephone, so if that is your planned method of follow-up, you may need to write to him again, rather than call.
