TY - JOUR
T1 - Development of case definitions for acute encephalopathy, encephalitis, and multiple sclerosis reports to the Vaccine Adverse Event Reporting System
AU - Ball, Robert
AU - Halsey, Neal
AU - Braun, M. Miles
AU - Moulton, Lawrence H.
AU - Gale, Arnold D.
AU - Rammohan, Kottil
AU - Wiznitzer, Max
AU - Johnson, Richard
AU - Salive, Marcel E.
N1 - Funding Information:
Robert Ball, M. Miles Braun, and Marcel E. Salive were employees of the U.S. Food and Drug Administration at the time this study was undertaken. Funding for Neal Halsey, Lawrence Moulton, and Richard Johnson was provided from the National Vaccine Program Office via the Food and Drug Administration. Funding for Arnold Gale, Kottil Rammohan, and Max Wiznitzer was provided by the Vaccine Injury Compensation Program, Health Resources and Services Administration. We appreciate the efforts of Rebecca Malouin and Lidia Propper in processing the data collected in this study.
PY - 2002/8/1
Y1 - 2002/8/1
N2 - The Vaccine Adverse Event Reporting System (VAERS), administered by the FDA and CDC, is the U.S. system for surveillance of vaccine adverse events (AE). Acute encephalopathy age <18 months (EO < 18), age ≥18 months (EO ≥ 18), encephalitis (EI), and multiple sclerosis (MS) after vaccination have been reported to VAERS, but reports often contain insufficient information to validate diagnoses. Standardized case definitions would enhance the utility of VAERS reports for AE surveillance. We developed practical case definitions for classification of VAERS reports, and three neurologists independently applied the definitions to reports submitted in 1993. Inter-observer agreement was assessed, and non-concordant classifications were reviewed in a follow-up conference call. Reports of EO < 18 (n = 8), EO ≥ 18 (n = 20), EI (n = 15), and MS (n = 16) were classified as "definite" in 7% to 30% of the cases, while 26% to 51% of reports were thought to have insufficient information to make a classification. Agreement among reviewers was good to excellent, (kappa: 0.65 to 0.85) except for EO < 18 m for which it was marginal (kappa: 0.37). It is possible to develop reproducible case definitions for acute encephalopathy, encephalitis, and multiple sclerosis using a standardized approach. Application of standardized case definitions to VAERS reports documents the limited information in many reports, specifies data for supplemental collection, and indicates that VAERS reports should be cautiously interpreted. Development and application of case definitions for other adverse events reported after vaccination should enhance the value of vaccine safety databases.
AB - The Vaccine Adverse Event Reporting System (VAERS), administered by the FDA and CDC, is the U.S. system for surveillance of vaccine adverse events (AE). Acute encephalopathy age <18 months (EO < 18), age ≥18 months (EO ≥ 18), encephalitis (EI), and multiple sclerosis (MS) after vaccination have been reported to VAERS, but reports often contain insufficient information to validate diagnoses. Standardized case definitions would enhance the utility of VAERS reports for AE surveillance. We developed practical case definitions for classification of VAERS reports, and three neurologists independently applied the definitions to reports submitted in 1993. Inter-observer agreement was assessed, and non-concordant classifications were reviewed in a follow-up conference call. Reports of EO < 18 (n = 8), EO ≥ 18 (n = 20), EI (n = 15), and MS (n = 16) were classified as "definite" in 7% to 30% of the cases, while 26% to 51% of reports were thought to have insufficient information to make a classification. Agreement among reviewers was good to excellent, (kappa: 0.65 to 0.85) except for EO < 18 m for which it was marginal (kappa: 0.37). It is possible to develop reproducible case definitions for acute encephalopathy, encephalitis, and multiple sclerosis using a standardized approach. Application of standardized case definitions to VAERS reports documents the limited information in many reports, specifies data for supplemental collection, and indicates that VAERS reports should be cautiously interpreted. Development and application of case definitions for other adverse events reported after vaccination should enhance the value of vaccine safety databases.
KW - Adverse events
KW - Encephalitis
KW - Encephalopathy
KW - Immunization
KW - Multiple sclerosis
KW - Safety
KW - Surveillance
KW - Vaccine
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U2 - 10.1016/S0895-4356(01)00500-5
DO - 10.1016/S0895-4356(01)00500-5
M3 - Article
C2 - 12384197
AN - SCOPUS:0036697763
SN - 0895-4356
VL - 55
SP - 819
EP - 824
JO - Journal of Clinical Epidemiology
JF - Journal of Clinical Epidemiology
IS - 8
ER -