Causal association analogy

The 1994 report of the Institute of Medicine concluded that the evidence was inadequate to accept or reject a causal relation between MMR and encephalopathy, and it is known that the incidence of encephalitis after measles immunization of healthy children tends to be lower than the observed incidence of encephalitis of unknown cause. Two large studies have been negative. In a study analogous to the British Childhood Encephalopathy Study there were no increased risks of either encephalopathy or neurological sequelae after measles immunization (19). A retrospective case-control study through the CDC Vaccine Safety DataUnk assessing the risk for 300 000 doses of MMR found not a single case of encephalitis/ encephalopathy within 30 days of the administration of MMR (20). In contrast, the review mentioned above (18) reported an association between measles vaccine and encephalopathy. However, the conclusion of the report of the Institute of Medicine is still valid, namely that evidence is stiU inadequate to accept or reject a causal relation between measles vaccine and these diseases. 

The final four criteria are plausibility, coherence, supportive experimental evidence and analogy - these are related by a theme of whether or not the association fits with existing scientific knowledge and beliefs. If so then causation is more likely but newly identified associations may not fit - so absence of any or all of these criteria does not preclude an association being causal. 

The motivation for the causal theory of reference and its criteria for referring to natural kinds has been a central question of how language relates to the world. Traditionally, expressions such as proper names refer to or designate an object because the name was associated with some descriptive content about the object in question. Analogously, general terms or nouns such as tiger , acorn , or element were considered to refer to objects by virtue of their sense where the sense provides the description of the object (Frege 1892). 

---