Hviid A, Thorsen NM, Thomsen LN, et al. - Although the human papillomavirus (HPV) vaccines are supported as safe by a growing body of evidence, concerns remain regarding autonomic dysfunction syndromes and non-specific symptoms. Traditional diagnostic classification schemes do not capture these conditions easily and hence call for innovative approaches to the study of vaccine safety which take more general measures of all-cause morbidity into account. The unique Danish registers, including regional registration of absence from school, were used to perform a cohort study of 14,068 adolescent Danish girls attending 5th through 9th grade in public schools in the municipality of Copenhagen during August 1, 2013–January 23, 2018. A total number of 6,206,188 school days with 213 221 days of absence from school due to illness (absence rate, 3.4%) were assessed in this study yielding important and novel contribution to HPV vaccine safety. Researchers here address important safety concerns without relying on medical diagnoses by using absence from school records. Per findings, the risk of morbidity did not enhance in any manner that manifests as absence from school due to illness, in correlation with HPV vaccination.