BackgroundThere is no global consensus on whether pandemic-related factors are related to child abuse. How the pandemic reinforces the risk factors of child abuse might depend largely on individuals’ current and past lifestyles in each country. Some changes of lifestyles continue after the pandemic, and it is important to understand which factors are strongly associated with child abuse. We analyzed the pandemic-related characteristics of offenders and non-offenders of self-reported child physical abuse from Internet survey data in Japan and discussed how the pandemic affected physical child abuse and what caused the difference by gender.MethodsWe conducted a cross-sectional study on physical child abuse by caregivers based on the Internet survey conducted from September to October 2021. We divided the participants who were living with their child aged less than 14 years into offenders and non-offenders based on the answer to the question about physical child abuse. The population distribution of the sample was compared to that of caregivers under the same conditions in a large Japanese dataset. The association between their characteristics and physical child abuse was analyzed by univariable and multivariable analysis.ResultsThe caregivers analyzed in the cohort had similar population distributions to those in the large Japanese dataset. As risk factors of male offenders, “work from home 4–7 days/week,” “decreased work,” “normal relationships with household members (compared to good relationships),” “COVID-19 infected, both themselves and household members, within a year,” “unwillingness to receive COVID-19 vaccination because the license process of the vaccine is doubtful,” “high levels of benevolent sexism,” and “history of child abuse” were observed. As risk factors of female offenders, “bad relationships with household members (compared to good relationships),” “fear of COVID-19,” “COVID-19 infected, both themselves and household members, within a year,” “feelings of discrimination related to COVID-19 in the past two months,” and “history of child verbal abuse” were observed.ConclusionsAmong male offenders, a significant relationship was observed regarding work-related changes, which may have been reinforced by the pandemic. Furthermore, the extent of the influence and fear of losing jobs caused by these changes may have varied according to the strength of gender roles and financial support in each country. Among female offenders, a significant relationship was observed regarding fear of infection itself, which is consistent with the findings of other studies. In terms of factors related to dissatisfaction with families, in some countries with prominent stereotyped gender roles, men are thought to experience difficulties adapting to work-related changes induced by crises, while women are thought to experience intense fear of the infection itself.