Estimating list inflation in a practice register

The reason why patients were incorrectly registered in an age-sex register was studied. Whereas underregistration was caused by patient delay in registering with a doctor, the much greater number of overregistered patients were thought to be there largely because of administrative delays in removing their names from the register. It is suggested that it would be possible for the software of a computer system in general practice to correct the population size and structure for estimated list inflation.