How reliable is parental/carer assessment of infant health status?

Problems often arise in cases of lethal inflicted injury in infants and children in determining the chronology of events. However, on occasion it may be assumed that a parent's statement that the child appeared normal at a particular time is correct. It is then inferred that the lethal injury occurred after this time. In a study of infants from Queensland, Australia a significant number of cases occurred where a parent/carer did not actually recognise that an infant was deceased or in extremis despite handling of the infants, some of whom had established rigor mortis. Assessment of their infant's health status was quite flawed, presumably due to inattention, fatigue, or confirmatory bias (seeing what is expected). This could also apply to infants with head injuries who may manifest quite non-specific signs such as lethargy, somnolence or alteration in conscious state, manifestations that could easily be confused with normal drowsiness or sleep. Thus, the evaluation of parent/carer statements must be tempered by the knowledge that their opinions may not always (for completely understandable reasons) be reliable, and should not be uncritically accepted as a basis for deciding the time course for a lethal process.