Space-Time Analysis of the California Birth Cohort: 30 Years of Childhood Cancer
Background: The cause of most childhood cancers remains a mystery. Even basic epidemiologic characteristics of children with cancer are not completely understood. Project Goal: This study seeks to describe where and when nearly every child with cancer in California for the last 30 years was born and diagnosed and to identify unusual patterns of disease occurrence and to ascertain if there are social disparities in childhood cancer. Methodology: Children with childhood cancers (25,518 cases) will be compared to healthy children (102,072 controls) drawn from the California Birth Cohort. We will examine the place and time of each major childhood cancer type and assess if cases occur in a definable pattern in space, time, or space-time. Investigating both the location of birth and diagnosis is a unique aspect of this study as exposures in utero or directly after birth may contribute substantially to disease. Non-random space-time groupings, sometimes referred to as clusters, may provide valuable information about risk factors and help to generate ideas on what causes the diseases. Most previous cluster investigations have been based on anecdotal observations of clinicians or parents. Our study, will be based on nearly the complete population of children born and diagnosed in California. This study will assess childhood cancers overall as well as individual types. The critical basic information obtained will aid researchers in understanding of environmental, social and molecular risk factors.