We conducted regression analyses to examine patient and injury characteristics associated with time spent in specific activities. Typical PBE analytic strategies does not compare one center to another because it is thought that center effects may result from underlying differences in patient, injury, or clinician characteristic; and thus, center identities were not entered into these models. However, we acknowledge that there may be additional center-specific factors that may also influence the amount of time spent on specific areas of care management or bedside education. And, indeed, when centers were allowed to enter the two regression models reported here (time spent in bladder management education and time nurses spent in interdisciplinary conferencing), the explanatory power more than doubled. For bladder education, center effects added about 30% to the explained variation. The majority of the variance in interdisciplinary conferencing (66% added) may be due to substantial differences in how conferencing is conducted at various centers. These increases suggest that focusing on patient and injury characteristics may be supplemented with center effects to help explain variation in time spent in specific areas of teaching and care management work done with patients at the bedside. The significant variation in time spent should prove useful in the eventual effort to correlate interventions with key patient outcomes.