Table 1

Comparison of smallpox vaccination adverse effects studies meeting selection criteria for this systematic review
Study and year published [Ref]	Source	Number of primary and re-vaccinations	Screening occurred	Complications	Numerator source		Denominator source

					Complication	Death

Neff 1967a [19]	United States, 1963	6,239,000 7,775,000	NR	PVE, VN, EV, GV, AI	Red Cross VIG distribution system, CDC, National Survey of pediatrician and general practitioners	Deaths certificates	Estimated by National Bureau of Census Immunization Survey
Neff 1967b [22]	United States, 1963 (North Carolina, Rhode Island, Washington, Wyoming)	298,000 370,000	NR	PVE, VN, EV, GV, AI	Retrospective physician survey, Local health officers, Records at major medical centers	Death certificates	Estimated by National Bureau of Census Immunization Survey
Lane 1969 [24]	United States, 1968	5,594,000 8,574,000	NR	PVE, VN, EV, GV, AI	Red Cross VIG distribution system, Red Cross consultants, State & Territorial Epidemiologists, Burroughs-Wellcome Co., Vaccine manufacturers, NCDC Encephalitic Surveillance Unit, NCDC Viral Exanthems Unit	Death certificates	Estimated by National Bureau of Census Immunization Survey
Lane 1970 [25]	United States, 1968 (Alabama, Alaska, Iowa, Kentucky, Maine, Maryland, Rhode Island, South Carolina, Washington, West Virginia)	596,000 998,000	NR	PVE, VN, EV, GV, AI	Prospective physician survey, Public health nurse survey (2 states)	NR	Estimated by National Bureau of Census Immunization Survey
Mellin 1970 [23]	United States, 1968 (Maryland)	109,000 166,000	NR	PVE, VN, EV, GV, AI	Medical and chirurgical faculty, County health officers, Chief pediatricians in general hospitals, Red Cross VIG distribution system, General hospitals, Public health nurses	NR	Estimated by National Bureau of Census Immunization Survey
Ratner 1970 [21]	Puerto Rico, 1967	369,546 465,926	Yes^a	PVE, VN, EV, GV, AI	Physician survey, Immunization nurses, University hospital dermatologists, Red Cross VIG distribution system	NR	National smallpox vaccination campaign
Neff 1972 [20]	United States, 1968 (Baltimore pediatric clinic)	549 433	NR	PVE, VN, EV, GV, AI	Pediatric clinic chart review	NR	Clinic chart review

NR = Not reported, PVE = post-vaccinial encephalitis, VN = vaccinia necrosum, EV = eczema vaccinatum, GV = generalized vaccinia, AI = accidental infection (inadvertant autoinoculation), VIG = Vaccinia immune globulin, NCDC = National Communicable Disease Center. ^aVaccinations withheld from persons aged less than 1 year or greater than 60 years, and persons with acute illness, blood dyscrasia, malignancy, pregnancy, eczema or infectious skin disease, eczema in household contacts, steroid therapy, radiation therapy; cerebral damage, or seizure disorder. ^bWyeth Dryvax product licensed and is use during this period [11]
Aragón et al. BMC Public Health 2003 3:26 doi:10.1186/1471-2458-3-26