“The Institute of Medicine (IOM) was charged by Congress when it enacted the National Childhood Vaccine Injury Act in 1986 with reviewing the literature regarding the adverse events associated with vaccines covered by the program, a charge which the IOM has addressed 11 times in the past 25 years. Following in this tradition, the task of this committee was to assess dispassionately the scientific evidence about whether eight different vaccines cause adverse events (AE), a total of 158 vaccine-AE pairs, the largest study undertaken to date, and the first comprehensive review since 1994.”

The committee concluded the evidence convincingly supports 14 specific vaccine–adverse event relationships. In all but one of these relationships, the conclusion was based on strong mechanistic evidence with the epidemiologic evidence rated as either limited confidence or insufficient.

Finding taken directly from the report:

• The committee concluded the evidence convincingly supports 14 specific vaccine–adverse event relationships. In all but one of these relationships, the conclusion was based on strong mechanistic evidence with the epidemiologic evidence rated as either limited confidence or insufficient.
• The committee concluded the evidence favors acceptance of four specific vaccine– adverse event relationships.
• The committee concluded the evidence favors rejection of five vaccine–adverse event relationships

• The vast majority of causality conclusions in the report are that the evidence was inadequate to accept or reject a causal relationship. Some might interpret that to mean either of the following statements: Because the committee did not find convincing evidence that the vaccine does cause the adverse event, the vaccine is safe – or – because the committee did not find convincing evidence that the vaccine does not cause the adverse event, the vaccine is unsafe.
• Neither of these interpretations is correct. “Inadequate to accept or reject” means just that—inadequate.

Read the report here.

“Heath Resources and Services Administration presented a list of specific adverse events for the committee to review (see [Table 1-1](https://www.nap.edu/read/13164/chapter/3#tab1-1) ). The selection criteria were described at the first committee meeting (Johann-Liang, 2009) as including the vast majority of adverse events in the claims for compensation. The committee added adverse events to the list if it identified epidemiologic studies or case reports. “