In 2021, Vlok et al. published evidence for thalassaemia at Man Bac, a Neolithic site in northern Vietnam. As the thalassaemia diagnostic protocol is a conservative one, there were several subadults who also presented with evidence of severe anaemia but did not necessarily possess the diagnostic cues specific for thalassaemia. The problem with thalassaemia is that it ultimately leads to fragile bones that preserve poorly in the archaeological record. Theoretically, many cases are being overlooked. However, thalassaemia causes marked expansion of the cranial vault and face. The aim of this research was to assess whether there were distinct differences in the craniofacial metrics of Man Bac subadults with or without thalassaemia and whether it was possible to identify more individuals who did not present with classically diagnostic signs -such as rodent facies (expansion of the facial region leading to snout-like facial deformity)- that are specific to thalassaemia and not overlapping with other anaemias. We measured the width at 25 different points in the skull and compared the results between thalassaemic and non-thalassaemic individuals as identified by the diagnostic protocol (n=30). We then analysed the distribution of each of these measurements and discerned that in excess of +/-1 SD was valuable for reviewing extra cases of thalassaemia. Two more individuals (a 1.5-year-old and a 2-year-old) were identified as statistical outliers with our new method and had lesion expressions corroborating a diagnosis of thalassaemia. A third had lesions consistent for rickets instead that is also known to increase the cranial width. Lastly, a T-test identified that facial features, especially maxillary width, provided the best measure for discerning thalassaemia (as outliers) from the overall sample. We conclude that metric analysis for the identification of thalassaemia in fragmented subadult remains is valuable but only in the context of other pathological lesions.