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. 2009 Sep 23;8:43. doi: 10.1186/1476-069X-8-43

Table 3.

Summary of Bradford Hill test results

Bradford Hill Guideline Explanation Result
1 Strength numbers large enough not to be chance observation yes
2 Consistency association observed by different persons, in different places and times yes
3 Specificity association limited to specific people/areas/effects yes
4 Temporality effects occur after exposure yes
5 Biological gradient association has biological gradient or dose-response relationship yes
6 Plausibility suspected causation fits biological knowledge of the day no
7 Coherence suspected causation accords with natural history and biology no
8 Experiment/animal studies other experimental evidence available not available
9 Analogy similar evidence from other studies yes
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