The validity of ecological studies in epidemiology for inferring causal relationships has been widely challenged as observed associations could be biased by the Ecological Fallacy. We reconsider the important design components of ecological studies, and discuss the conditions that may lead to spurious associations. Ecological associations are useful and valid when the ecological exposures can b...

Ecological studies, which consider patient groups rather than individuals, are common in health policy research. The ‘ecological fallacy’ is a well-recognised methodological concern, but in this perspectives paper, we focus on less often appreciated but equally important limitations of such studies. In particular, we consider reliability and power as they apply to ecological studies, and make r...

Recently, there has been an increased interest in modeling the association between aggregate disease counts and environmental exposures measured, for example via air pollution monitors, at point locations. This paper has two aims: first, we develop a model for such data in order to avoid ecological bias; second, we illustrate that modeling the exposure surface and estimating exposures may lead ...

"The authors show how data from the 2% Sample of Anonymised Records (SAR) can be combined with data from the Small Area Statistics (SAS) database to investigate the causes of the ecological fallacy in an Enumeration District (ED) level analysis. A range of census variables are examined in three ¿SAR districts'...in England. Results of comparable analyses from the 1986 Australian census are also...

After more than a century of research the typical growth pattern of a tree was thought to be fairly well understood. Following germination height growth accelerates for some time, then increment peaks and the added height each year becomes less and less. The cross sectional area (basal area) of the tree follows a similar pattern, but the maximum basal area increment occurs at some time after th...

Biologists often cope with variation in physiological, environmental and ecological processes by measuring how living systems perform under average conditions. However, performance at average conditions is seldom equal to average performance across a range of conditions. This basic property of nonlinear averaging - known as 'Jensen's inequality' or 'the fallacy of the average' - has important i...

The author examines problems related to the fact that in many countries, census data are only reported for areal units and not at the individual level. Attention is paid to the question of ecological fallacy problems that arise from this situation. Data from a 10 percent sample of the United Kingdom population and individual census data from Italy are used to illustrate the problem. "It is c...

Using an ecological study design, Gordon et al. (Isr J Health Policy Res 6:39, 2017) demonstrate variations in mortality patterns across districts and sub-districts of Israel during 2008-2013. Unlike other epidemiological study designs, the units of analysis in ecological studies are groups of people, often defined geographically, and the exposures and outcomes are aggregated, and often known o...