Loading
Eight of ten north-western Russian cancer registries were judged complete enough for research, but Saint Petersburg, the largest, fell below 90 per cent, and about a tenth of its cases never reached the national annual report.
The same ten population-based registries, covering 13 million people, were assessed for completeness and timeliness using historic-data methods against European reference rates, mortality-to-incidence ratios and death-certificate methods, with the Lincoln-Petersen estimator and the Ajiki formula used to estimate unregistered cases.
Incidence trends were stable except in Leningrad oblast, with a slight fall in older age groups against European reference rates for several sites. Completeness was above 90 per cent in most regions, low or implausible in Leningrad oblast and below 90 per cent in Saint Petersburg. The national annual report for 2008 to 2017 omitted about 10 per cent of the cases later held in the Saint Petersburg registry database; the same gap was below 3 per cent for Arkhangelsk, Murmansk, Novgorod and Vologda oblasts and the Republic of Karelia.
The national figures published each year are the sum of regional reporting forms, not of the registry databases, and the two differ. Anyone comparing Russian incidence with another country's should know which of the two they are reading.