Sample size and representational bias in bioarchaeology: A case study of stature estimation from medieval Prussia

Abstract

AbstractFor bioarchaeological studies, a common approach to estimating stature is via regression formulae that are based on the scaling of skeletal elements relative to overall height. Both stature and the proportions of contributing elements may be affected by biocultural and ecological factors, and thus, it is generally preferable to apply population‐specific formulae when possible. Within bioarchaeology, the establishment of population‐specific regression formulae is complicated by the need to base formulae on a sufficiently large number of individuals for which all skeletal elements contributing to stature can be measured. Yet disciplinary conventions within bioarchaeology suggest the need for sample sizes that are larger than typical within related fields, and it is thus possible that disciplinary status quo has led to a systematic bias in the literature toward larger sites, regions with relatively good preservation, and populations associated with these aspects. To investigate the efficacy of combined‐sex stature regression formulae based on relatively small samples, this study calculated population‐specific formulae based on long bone length for 22 individuals from a late medieval Old Prussian cemetery at Bezławki, Poland. The relationship between stature and each of the predictor elements/measurements considered was strong, particularly for maximum femoral length (r = 0.976). For the latter measurement, a sample size as small as 18 produced accurate and precise stature estimates. Further, the Bezławki‐specific formula based on maximum femoral length provided estimates of the stature that performed better than or similar to formulae based on larger populations, supporting that population‐specific formulae may be warranted, even when based on small samples.