Magana: Jonas Salk da wata ƙungiya a Jami'ar Pittsburgh da suka haɗa da Julius Youngner, Byron Bennett, L. James Lewis, da Lorraine Friedman, wanda ya buƙaci shekaru na gwaji na gaba. Salk ya tafi gidan rediyo na CBS don bayar da rahoto game da gwajin nasara a kan karamin rukuni na manya da yara a ranar 26 ga Maris 1953; kwana biyu bayan haka, an buga sakamakon a JAMA. Farawa a ranar 23 ga Fabrairun 1954, an gwada rigakafin a Makarantar Arsenal da Watson Home for Children a Pittsburgh, Pennsylvania. An yi amfani da rigakafin Salk a cikin gwajin da ake kira Francis Field Trial, wanda Thomas Francis ya jagoranci, mafi yawan gwaji na likita a tarihi a wannan lokacin. An fara gwajin tare da kimanin yara 4,000 a Franklin Sherman Elementary a McLean, Virginia, kuma a ƙarshe yara miliyan 1.8, waɗanda suka haɗa da jihohi 44 daga Maine zuwa California. Daga ƙarshe, binciken ya ƙunshi kimanin yara 440,000 da aka yi wa allurar rigakafi ba tare da cutarwa ba tare da cutarwa ba, sannan aka lura da yawan yara miliyan 1.2 da aka yi wa allurar rigakafi a cikin rukuni
Yara miliyan 1.8