The survey of the semi-super and supercentenarian population

The survey of the semi-supercentenarian population collects information about alive or dead resident population over the age of 105 (called semi-super and supercentenarians) with the aim of providing a longitudinal database of this population.

Data source is administrative, it is the Istat survey of the resident population by gender, year and marital status (Posas) on 1 January of each year. To all municipalities that have at least one semi-super or supercentenarian resident are asked the living existence or death certificates and some additional demographic information is collected.

People still alive at the age of 105 are followed up every year until their death with the recording of the date of the event: as long as the individual remains alive, the validation process never stops and every year ISTAT also proceeds to "revalidate" backwards the data observed in the past. Therefore, the data quality check for the database is performed retrospectively on a daily basis. Furthermore, the data collected by the survey are periodically subjected to record linkage operations with other Istat surveys for the improvement of data quality.

Institutional households: group of people that, without ties of marriage, kinship, affinity or similar, live together for reasons of faith, care, assistance or for military, penal or other reasons.  The main types of institutional households are: educational, welfare, public and private healthcare, penitentiary, ecclesiastical, military institutions, hotels, pensions, lodging houses, merchant ships, other institutional households (for example, dormitories for students and workers, etc.).

Cohort: a group of persons who experience a certain event in a specified period of time.

Resident Population: constituted in each Municipality (and similarly for other territorial divisions) of people with habitual residence in the Municipality itself. Persons temporarily residing in another Municipality or abroad, for the exercise of seasonal occupations or for reasons of limited duration, do not cease to belong to the resident population.

Probability of dying: the probability that a person of exact age x will die before reaching age (x +n) and it permits the calculation of the further biometric functions included in the life-table.

Semi-supercentenarians: people who reached and overpassed 105 years of age.

Supercentenarians: who reached and overpassed 110 years of age.