Rules of inference:
(1) time order (page 118)
(2) strength of association (page 118)
(3) specificity (a) in effects of a cause and (b) in causes of an effect (page 120)
(4) consistency on replication (page 122)
(5) coherence in (a) theortical plausibility, (b) in biology, (c) in facts, and (d) in statistical analysis with a dose response (monotonic) (pages 124 to 126)
Findings strongly against causation:
(1) time order incompatible
(2) consistency on replication negative
(3) factual coherence incompatible
Findings against causation:
(1) no strength of association
(2) theoretical coherence implausible
(3) biology incoherent
Findings for causation:
(1) strength of association strong
(2) theoretical coherence plausible
(3) biology coherent
(4) factual coherence compatible
Findings strongly for causation:
(1) strength of association very strong
(2) specificity in causes of an effect high
(3) consistency on replication positive
(4) dose response (monotonic)
