This study aims to determine whether the age-specific incidences (1) of publicly reported cases of shaken baby syndrome (SBS) and (2) of publicly reported cases of SBS with crying as the stimulus have similar properties to the previously reported normal crying curve.
The study reports cases of SBS by age of the child at the time of the inflicted trauma from the data set of the National Center on Shaken Baby Syndrome using cases entered between January 1, 2003 and August 31, 2004.
There were 591 cases of infants up to 1.5 years of age who had been reported to have been shaken or shaken and physically abused. Of these, crying was reported as the stimulus in 166 cases. In both samples, the curves of age-specific incidence started at 2–3 weeks, reached a clear peak at about 9–12 weeks of age, and declined to lower more stable levels by about 29–32 weeks of age, similar to the normal crying curve. These curves have similar onsets and shapes and a slightly later peak compared to the normal crying curve.
The findings provide convergent indirect evidence that crying, especially in the first 4 months of age, is an important stimulus for SBS.
From the *Centre for Community Child Health Research, Child and Family Research Institute, Vancouver, BC, Canada; †Department of Pediatrics, University of British Columbia Faculty of Medicine, Vancouver, BC, Canada; and ‡National Center on Shaken Baby Syndrome, Ogden, UT.
Received August 2006; accepted December 2006.
Supported by a Child and Family Research Institute Establishment Grant and Canada Research Chair for Community Child Health Research funds to R.G.B.
Address for reprints: Ronald G. Barr, MDCM, FRCPC, Centre for Community Child Health Research, 4480 Oak Street, L408, Vancouver, BC V6H-3V4, Canada; e-mail: firstname.lastname@example.org.