Study designs of evaluations included in the review
Reviews, expert opinions, consensus guidelines and studies that were methodologically flawed were excluded. In all of the included studies, the data were collected retrospectively.
Specific interventions included in the review
Studies of external closed CPR were eligible for inclusion. Where reported, the duration of resuscitation in the included studies ranged from 1 to 540 minutes and resuscitation was performed by medical personnel, bystanders, or a combination of both. None of the included studies described the CPR technique.
Participants included in the review
Studies of children (aged up to 18 years) with no underlying bone disease were eligible for inclusion. Studies with mixed populations of adults and children were excluded if the results for children were not reported separately. The included studies were in children aged 0 to 14 years. Five of the six included studies excluded prior child abuse. Five studies evaluated children who had died; the sixth evaluated children who had survived.
Outcomes assessed in the review
Studies that assessed rib fractures were eligible for inclusion. The included studies collected outcomes data from medical case reports, radiographic examinations and autopsy reports. Five of the six studies obtained information about rib fractures at postmortem examination; in the sixth, rib fractures were identified using chest X-rays after CPR (64% of children had only early post-resuscitation X-rays and the others had follow-up X-rays at 2 weeks). None of the studies used specimen radiography.
How were decisions on the relevance of primary studies made?
The studies were selected for inclusion at two independent reviews undertaken by a panel of 27 reviewers. Any disagreements were resolved at a third review.