infants and the elderly, these are the ages for which error due to age misstatement and underreporting of deaths is most likely to occur. In this chapter, we first discuss problems with Soviet data on infant mortality and the elderly as a general caution to researchers who are not familiar with data from the region. In the data analysis, however, we focus on an age range for which we can have more confidence in the data. For much of the analysis, we examine data for ages 10-79; for some of the analysis, though, we focus on the age range 20-59.
Our approach to studying demographic trends in the former Soviet Union and the NIS is to start with official statistics, but to view them with a critical eye. Scholars have devoted less attention to the evaluation and adjustment of demographic statistics in this region than to the evaluation and adjustment of economic statistics.1 We do not subscribe to the view that all of the data from the Soviet Union were fabricated or intentionally altered to make the state or political leaders look good or to mask negative trends in popular welfare. A frequent concomitant of such a point of view is a readiness to accept official data from the region only when they reveal negative trends or facts.
Nor do we subscribe to the view that the data are ''in the ballpark" and reliable enough for designing appropriate health and welfare interventions. While we agree that the available data provide a fairly clear picture of the main problems in public health and welfare for some regions and purposes, issues of data quality are too substantial to ignore. Acceptance of reported mortality data at face value would lead to errors in evaluating the impact of intervention strategies, because changes in data quality can obscure changes in real demographic behavior or outcomes. Moreover, some of the mortality rates, including cause-specific rates, have been extremely volatile in response to short-term factors and may now be at or near their peaks. Consequently, there is considerable risk of confusing the effects of policy interventions with "regression effects."2
We assess the plausibility of the reported figures by looking for internal consistency and by comparing them with levels and patterns in reported statistics from other countries. On occasion, formal tests for the consistency of age and mortality data have been applied to data from the Soviet Union and the NIS. Because of the lack of needed data, however, the formal application of consistency checks is not yet feasible for most regions of the former Soviet Union and for most types of mortality data. Furthermore, some methods for estimating error require untenable assumptions about the data. For example, methods of estimating the underregistration of deaths using vital registration and intercensal survival rates work reasonably well only if there is no appreciable age exaggeration in the census or death registration, a precondition that does not exist in data from Central Asia. Hence, a naive application of so-called formal checks for completeness of registration would give a false impression (most likely an underestimate) of the extent of underreporting of mortality in this region.
We have devoted a great deal of effort to examining the demographic information system in this part of the world and what biases it might impart. Often we