THE CENTRAL REGISTER, WHICH IS MAINTAINED BY ONTARIO'S MINISTRY OF COMMUNITY AND SOCIAL SERVICES, CHILD WELFARE BRANCH, RECEIVED 1,603 REPORTS OF CHILD ABUSE FROM CHILDREN'S AID SOCIETIES FROM 1966 THROUGH 1970. THERE WERE 40 DEATHS OF CHILDREN UNDER AGE 5 IN WHICH PHYSICAL ABUSE OR CRIMINAL NEGLIGENCE WAS THE PROBABLE CAUSE. THE STUDY, WHICH INCLUDED DETAILED ANALYSES OF CASES, FOUND THAT PHYSICAL ABUSE OF CHILDREN IN ONTARIO IS NOT LIMITED TO VERY YOUNG CHILDREN, ALTHOUGH THE VERY YOUNG OFTEN SUFFER THE MOST SERIOUS INJURIES AND ARE MORE LIKELY TO DIE FROM THEIR INJURIES THAN ARE OLDER CHILDREN. ANALYSIS OF 359 CASES OF ABUSE INVOLVING 397 CHILDREN REPORTED TO THE CENTRAL REGISTER IN 1970 FOUND THAT MORE THAN ONE-THIRD OF THE CHILDREN RECEIVED ONLY BRUISES OR WELTS, AND THAT 10 PERCENT HAD NO APPARENT INJURY. FIFTEEN PERCENT WERE INJURED SUFFICIENTLY TO REQUIRE HOSPITAL ADMISSION. MORE MEN THAN WOMEN WERE REPORTED AND VERIFIED AS HAVING ABUSED THEIR CHILDREN. EXCESSIVE USE OF DISCIPLINE, NOT DELIBERATE OR MALICIOUS ABUSE OR NEGLECT, WAS THE MOST APPARENT CAUSE OF INJURIES. IT WAS CONCLUDED THAT, ALTHOUGH THE INCIDENCE OF CHILD ABUSE IN ONTARIO PROBABLY IS GREATER THAN REPORTS TO THE REGISTER INDICATE, THE NOTION THAT A VERY GREAT NUMBER OF CASES GO UNREPORTED IS NOT SUBSTANTIATED. HOWEVER, IT WAS ALSO CONCLUDED THAT PHYSICIANS HAVE BEEN RELUCTANT TO REPORT SUSPECTED ABUSE, PARTICULARLY WHEN EVIDENCE CANNOT BE SUBSTANTIATED. THE STUDY'S FINDINGS ON THE CAUSES OF CHILD ABUSE AND DEATH, THE CHARACTERISTICS OF ABUSERS, AND THE CIRCUMSTANCES SURROUNDING ABUSE ARE SUMMARIZED. A TYPOLOGY OF ABUSIVE SITUATIONS--PSYCHOLOGICAL REJECTION, ANGRY AND UNCONTROLLED DISCIPLINARY RESPONSE, ABUSE BY BABY SITTERS, PERSONALITY DEVIANCE AND REALITY STRESS, CHILD-ORIGINATED ABUSE, CARETAKER QUARRELS--IS NOTED. SOURCES OF REFERRAL OF ABUSE CASES TO CHILDREN'S AID SOCIETIES (SCHOOLS, NATURAL MOTHERS, NEIGHBORS, HOSPITALS, POLICE, FAMILY RELATIVES, PRIVATE PHYSICIANS, PUBLIC NURSES--IN ORDER OF FREQUENCY) ARE IDENTIFIED. CHILDREN'S AID SOCIETY INTERVENTION IN ABUSE CASES IS DESCRIBED, AS ARE LEGAL ACTIONS TAKEN AGAINST ABUSERS. THE PROCESS OF CHILD ABUSE REPORTING IN ONTARIO IS REVIEWED, WITH EMPHASIS ON SHORTCOMINGS OF THE CENTRAL REGISTER. PROBLEMS WITH THE RECORDKEEPING PRACTICES OF THE CHILDREN'S AID SOCIETIES ARE ALSO NOTED. HIGHLIGHTS FROM PRESS COVERAGE OF CHILD ABUSE INCIDENTS ARE REVIEWED. SUPPORTING DATA ARE PROVIDED. (LKM)