## Bennett-Horiuchi Method

Some methods compare data from independent sources (direct capture-recapture approaches) while others are analytic indirect methods based on assumptions on the population age distribution. The basic idea behind these indirect methods is that everyone who reaches a given age must die at an older age. By making some assumptions it is possible to compare deaths by age to the population by age.

The Bennett-Horiuchi Method is an indirect approach to estimating the completeness of death registration data. For any population, the entry rate minus the growth rate must be equal to the exit or death rate. Systematic differences between the entry rate and the growth rate (which is a residual estimate of the exit rate calculated from the census age distributions) and the exit rate (calculated from information on deaths by age) is used to identify differences in reporting of population and of deaths. The magnitude of the inconsistency can be interpreted as a measure of completeness of death reporting relative to population reporting and can then be used to adjust the mortality estimates calculated from the original data.

Bennett-Horiuchi uses the population age distributions from two separate enumerations to estimate the growth rate as well as data on deaths registered in the intercensal period.

Its advantage is that it does not assume the population is stable and so can be used when the population distribution is changing.

Its limitation is that it is however vulnerable to changes in the coverage of the two censuses.

All indirect approaches assume that misreporting of deaths is constant across the age groups in the population or part of a population under consideration, such as people of a given age or older. Since this is unlikely to be true for child deaths, the approach is usually applied to adult mortality. The method provides information on when this assumption is violated and thus when the method becomes inappropriate.

An alternative way of avoiding the assumption of population stability is provided by Courbages and Fargues (1979). Their approach assumes constant under-reporting of deaths by age and compares model life table measures to the extent to which reported deaths are concentrated in old age. It can be applied to populations affected by migration.

Bennett, NG & Horiuchi, S (1984) Mortality estimation from registered deaths in less developed countries. Demography, 21(2): 217-34. |

Bennett, NG & Horiuchi, S (1981) Estimating the completeness of death registration in a closed population. Population Studies; 47(2):207-21. |

Hill, K (1987) Estimating census and death registration completeness. Asian and Pacific Population Forum; 1(3):8-13. |

Courbage, Y & Fargues, P (1979) A method for deriving mortality estimates from incomplete vital statistics. Population Studies; 33: 165-80. |

Example exercise from WHO |

Mortpak computer software including the Bennett-Horiuchi technique and other methods can be purchased from the United Nations:

Mortpak Description and order form |

MortPak Manual |