Childhood Conditions and Exceptional Longevity

A number of previous studies found interesting links between the early-life experiences and a subsequent mortality in later life. Such findings justify further advancement of these studies by exploring possible links between childhood conditions and exceptional longevity (survival to 100 years). However a number of methodological issues have to be resolved (such as data availability, quality, as well as research approaches), before starting a comprehensive research project on childhood predictors of exceptional longevity. This paper represents an attempt to do a preliminary study of related methodological issues in order to ensure feasibility of the subsequent large-scale research efforts. The following questions are explored in this study: Where to get data on exceptional longevity and childhood conditions? What is the quality of this data, and how can this data quality be checked and improved? What methods of data analysis to use? What are the hypotheses to test, and what are the preliminary findings to validate? The study presents a detailed analysis of available data resources on exceptional longevity and childhood conditions, a rigorous evaluation of data quality and testing different approaches to improve the quality of the data. As a result of these methodological explorations the following multi-step procedure of data collection and data cleaning has being suggested and tested in practice: Step 1. To extract data on alleged centenarians and their childhood conditions from computerized genealogies, pre-selected on the basis of their expected sufficient data quality (a number of indicators of data quality has been identified for this purpose). Following this procedure we extracted detailed family data for 991 alleged centenarians born in 1875-1899 in the United States from publicly available computerized genealogies of 75 million individuals identified in our previous study (Gavrilova, Gavrilov, 1999). Step 2. To validate the claims of exceptional longevity by cross-checking these records with the US Social Security Administration database on deceased person for the entire US population. Step 3. To double-check the validated centenarian claims again for the accuracy of birth date information by matching the records with the early US Censuses (1900, 1910, 1920 and 1930). Step 4. To enhance further the quality of records with confirmed exceptional longevity by adding information on childhood conditions available in the early US Censuses. This multi-step procedure of data collection and quality evaluation is described in this paper in great detail, to demonstrate how this approach works in practice. A new validated dataset on exceptional longevity …