The osteological paradox addresses how well interpretations of past population health generated from human skeletal remains reflect the health of the living population from which they were drawn. Selective mortality and hidden heterogeneity in frailty are particularly relevant when assessing childhood health in the past, as subadults are the most vulnerable group in a population and are therefore less likely to fully represent the health of those who survived. The ability of subadults to represent the health of those who survived is tested here by directly comparing interpretations of childhood stress based on non-survivors (subadults aged 6-20,14 females and 9 males) to those based on retrospective analyses of survivors (adults aged 21-46, 26 females and 27 males). Non-survivors and survivors were directly matched by birth year, using the Coimbra Identified Skeletal Collection; therefore interpretations of childhood stress reflect a shared childhood. Long bone and vertebral canal growth, linear enamel hypoplasia, cribra orbitalia, porotic hyperostosis, scurvy indicators and periosteal bone reactions were assessed for both groups. Overall, long bone growth generates the same interpretation of health for both non-survivors and survivors, and both groups exhibit the same range of stress (mild to severe), but the pattern of stress experienced in childhood differs between the two groups. Female survivors reveal different timing of stress episodes and a higher degree of stress than female non-survivors. Male survivors exhibit less stress than male non-survivors. These different patterns suggest that interpretations based solely on non-survivors would under-represent the stress experienced by female survivors and over-represent the stress experienced by male survivors, further demonstrating the importance of addressing issues of selective mortality. In addition, these different patterns suggest that hidden heterogeneity of frailty may be sex specific where males are more vulnerable to stress and females more able to develop resistance to stress and survive.

The osteological paradox addresses how well interpretations of past population health generated from human skeletal remains reflect the health of the living population from which they were drawn. Selective mortality and hidden heterogeneity in frailty are particularly relevant when assessing childhood health in the past, as subadults are the most vulnerable group in a population and are therefore less likely to fully represent the health of those who survived. The ability of subadults to represent the health of those who survived is tested here by directly comparing interpretations of childhood stress based on non-survivors (subadults aged 6-20,14 females and 9 males) to those based on retrospective analyses of survivors (adults aged 21-46, 26 females and 27 males). Non-survivors and survivors were directly matched by birth year, using the Coimbra Identified Skeletal Collection; therefore interpretations of childhood stress reflect a shared childhood. Long bone and vertebral canal growth, linear enamel hypoplasia, cribra orbitalia, porotic hyperostosis, scurvy indicators and periosteal bone reactions were assessed for both groups. Overall, long bone growth generates the same interpretation of health for both non-survivors and survivors, and both groups exhibit the same range of stress (mild to severe), but the pattern of stress experienced in childhood differs between the two groups. Female survivors reveal different timing of stress episodes and a higher degree of stress than female non-survivors. Male survivors exhibit less stress than male non-survivors. These different patterns suggest that interpretations based solely on non-survivors would under-represent the stress experienced by female survivors and over-represent the stress experienced by male survivors, further demonstrating the importance of addressing issues of selective mortality. In addition, these different patterns suggest that hidden heterogeneity of frailty may be sex specific where males are more vulnerable to stress and females more able to develop resistance to stress and survive.