A trauma frequency analysis was undertaken on a skeletal sample (n = 75) from the skeletal collections of the medieval Augustinian Priory of St. Mary Merton and the post-medieval lower cemetery of St. Bride’s Church. Fourty-four individuals exhibited trauma on one or more cranial elements. Cranial bones were arranged in different groupings for analysis: inclusive samples of 100% complete, at least 75% complete, at least 25% complete, entire sample; and independent samples of 100% complete, 75 - <100% complete, 25 - <75% complete, and <25% complete. Crania were categorized as 100% complete and incomplete. Four frequencies were calculated (frequency of lesions, of individuals with lesions, of individuals with multiple lesions, and the number of lesions per injured individuals) for each category and cranial element. The results illustrate a general trend towards a decrease in frequency as more fragmentary material is included, illustrating that including the more fragmentary material may bias the results towards underestimating trauma frequencies. However, Fisher’s exact tests do not show statistically significant differences between frequencies in the independent samples analysis, except for individuals with lesions on the right nasal bone. Further research into the effect of fragmentation and poor preservation in skeletal research, cranial trauma research in particular, is required. / Graduate