FINDINGS FROM LONGITUDINAL COHORT STUDIES - GOTHENBURG AND JERUSALEM

The longitudinal study of age-homogeneous cohorts is a powerful tool t o elucidate age-related changes and to attempt to distinguish normal a ging from the effects of disease. Many influences, such as the effect of changing lifestyle, medical practices and environmental factors wit h time must be considered when designing and interpreting such studies . Cross-cultural differences manifest in comparing different studies m ust also be accounted for, but alternately provide a tool to distingui sh between endogenous and exogenous factors influencing human aging. T he first stage of the longitudinal study of 70 year olds in Gothenburg , Sweden, a cross-sectional survey performed in 1971, is compared to a similar cross-sectional survey performed in Jerusalem in 1991 as part of a projected longitudinal study. The similarities between the two c ohorts with regard to living conditions, functional independence and d isease prevalence are striking. There are also significant contrasts t hat reflect the 20 years that elapsed between the execution of the two studies, as well as the cultural and social differences. In particula r, the ethnic diversity of the Jerusalem population, hailing from 40 s eparate countries, is emphasized. The comparison of these two studies highlights many of the principles critical to the role of longitudinal cohort studies in gerontology.