Sir, In response to your call and follow-up letter for a historical commentary on the differences between Dr. Caffey's paper (AJR 1946; 61: 163-173) and mine (AJR 1953; 69: 413-427) in relation to parental or custodial factors in what is now recognized as child abuse, I can summarize the features as follows. Let me first make it clear that Dr. Cafffey was aware of these factors at the time that his paper was published and, as in so many other things, I learned about them from him. I had been with him just nine months (a glorious gestation period) when his paper was published and had been exposed to his ideas on the subject in the course of conversations prior to its actual appearance. He was quite convinced that the traumas resulting in the subdural hematomas and in the unusual skeletal lesions were causally related and most likely reflected parental malfeasance. In fact, if one reads his 1946 paper, there is ample evidence Of his suspicion of parental or custodial abuse: ".recognized injuries may be denied by mothers and nurses because injury to an infant implies negligence on the part of its caretaker." (p. 172, col 2); and further down the page referring to two separate patients: "In each case, unexplained fresh fractures appeared shortly after the patient had arrived home after discharge from the hospital. In one of these cases the infant was clearly unwanted by both parents and this raised the question of intentional illtreatment of the infant; the evidence was inadequate to prove or disprove this point." It is my belief that he didn't go further because he was concerned about possible legal repercussions if he were to publish his opinion and therefore steered clear of direct accusation. He did however go a little further in the 2nd edition of "the Book" (1950) in which (p. 686-7) he described lesions in the forearm of a 4 month old infant jerked by her mother to prevent a fall from a table, the mother having initially denied any traumatic incident but who admitted the episode "to direct questioning in the X-ray department after the film was made". He added that the admission illustrated "the unreliability of history for trauma to infants by mothers and nurses when the usual casual history of trauma is taken". The patients who were the subjects of my presentation in 1951 (published 1953), came to my attention in 1948 to 1950. I remember bringing films to a meeting of the American Pediatric Society in Atlantic City in 1949 or 1950 to show them to Jack and see if he agreed with my interpretation. He and Harry Bakwin went over them with me and did agree. But Jack cautioned me about implicating the parents as the perpetrators. I distinctly remember saying something to the effect that he had taught me to be critical of what people said and that also meant being critical of him too, and he beamed at me and he and Harry had a good laugh. Harry published two papers subsequently, one in 1952 and another in 1956. In the latter, following my paper and the very important one of Woolley and Evans, parental abuse was discussed. Much of the early emphasis was on the recognition of the "peculiar" bone lesions as a result of trauma an intellectual exercise. My direct statement that parents may be unaware of the trauma, may recognize it but forget or be reluctant to admit it, or may deliberately injure the child but deny it was an example of fools rushing in where angels feared to tread. Actually, it wasn't until Henry Kempe coined the term "the battered child" for our symposium at a plenary session of the American Academy of Pediatrics meeting in 1961 that the societal implications of the condition became more important than the categorization of bizzare radiographic images as a manifestation of trauma. But it all was derived from Jack's need to explain the nature of "R6ntgen's pallid shades . . . "