Objective: This study examined the power of child, perpetrator, and socio-economic characteristics to predict injury in cases of reported child physical abuse. The study was designed to assess the validity of the assumption that physically injurious incidents of child physical abuse are qualitatively different from those that do not result in injury, that their generative factors are distinctive, and that the quality of caregiving in these two types of incidents is different. Method: A weighted, nationally representative sample of 8,164 substantiated punishment abuse cases in Canada was used. Various models were constructed and evaluated through logistic regression. Results: Of six potential predictors--child age, perpetrator sex, child functioning, parent functioning, economic stress, and social stress--none predicted injury to the child. Conclusions: The findings suggest that injurious and non-injurious physical abuse cannot be distinguished on the basis of the personal characteristics or circumstances of the child or perpetrator. Practice implications: A common criterion for child welfare intervention into cases of suspected physical abuse is injury or risk of injury. This criterion assumes that injurious and non-injurious assaults are qualitatively different phenomena, predicted by different risk factors. In the present study an attempt was made to differentiate between injurious and non-injurious cases of punitive physical abuse on the basis of characteristics of the child, perpetrator, family, and social context. None of these factors explained the likelihood of injury, suggesting that the prediction of injury as an intervention criterion may be questionable. (Contains 6 tables.)