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Statistics According to research by the advocacy web site kidsandcars.org , back up collisions were the leading cause ( 34 % ) for U.S. non-traffic fatalities of children under 15 from 2006 – 2010 .
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Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: location, person, organization 
Text: {0} 
Answer:
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