Incidence of salivary gland tumours in Scotland: accuracy of national records.

Statistics on discharge diagnoses in Scotland during 1968-74 show the incidence of all tumours of major salivary glands to exceed 40/million population yearly. This is higher than in any other nationality except Canadian Eskimos. Studies in two hospitals showed that numerous errors occurred in reporting these tumours, but the figures were more likely to be too low than too high. Probably eastern Scotland at least has an unusually high incidence, although in other countries using different methods of analysis the reported figures are likely to be low. Statistics based on discharge diagnoses will continue to be neglected in research until the standard of completion of discharge diagnoses improves.