Why Bruises Cannot Be Reliably Dated by Their Color

In children, a bruise's color cannot reliably establish how old it is. A systematic review of the medical literature on bruise dating found that any color can appear in fresh, intermediate, and old bruises alike, and Maguire 2005 concluded that estimating a bruise's age from its color has no scientific basis and should be avoided in child-protection proceedings. This conclusion concerns clinical and photographic assessment of bruises in children.

The 2005 systematic review examined how accurately clinicians could estimate bruise age from visual assessment. Accuracy in aging a bruise to within 24 hours came in at less than 40%, whether the assessment was done in person or from a photograph (Maguire 2005). The review's authors stated their conclusion plainly: a bruise cannot be accurately aged from clinical assessment or a photograph.

A separate study tested this directly using bruises of known age. Fifty children with accidental bruises of documented age were assessed by emergency pediatricians who were kept blind to the children's history. Their accuracy in aging a bruise to within 24 hours was only 47.6% (Bariciak 2003). Individual accuracy across the examiners ranged from 0% to 100%, and agreement between different examiners looking at the same bruise was poor, with a kappa value of -0.03, indicating essentially no agreement above chance (Bariciak 2003). The cues clinicians commonly relied on when estimating age, including color, tenderness, and swelling, were not significantly correlated with accuracy in that study.

What this does and does not mean

This body of research concerns visual and photographic dating of bruises in children, not histologic dating performed at autopsy, which is a separate literature and is not addressed here. It does not mean that injuries can never be timed by any method in any context. It does mean that a clinician or examiner who states, from color alone, that a bruise occurred within a specific narrow time window is offering an opinion the current research does not support. This limitation applies regardless of which side of a case is asking the question.

In casework, bruise-age testimony often carries significant weight in establishing a timeline or placing a caregiver inside or outside a window of opportunity. The research summarized here constrains that kind of testimony for any expert, including this one. An opinion about when a bruise occurred should be grounded in what the literature actually supports, and color-based aging to a specific time window is not among it.

The studies cited below are indexed in PubMed; DOI links are provided.

References

1. Maguire S, Mann MK, Sibert J, Kemp A. Can you age bruises accurately in children? A systematic review. Arch Dis Child. 2005;90(2):187-189. doi:10.1136/adc.2003.044073
2. Bariciak ED, Plint AC, Gaboury I, Bennett S. Dating of bruises in children: an assessment of physician accuracy. Pediatrics. 2003;112(4):804-807. doi:10.1542/peds.112.4.804