Intra-laboratory variations using dual-photon absorptiometry

A letter by R.B. Mazers et al. (see ibid., vol.28, no.6, p.747-8, 1983) is commented on. That letter commented on a scientific note by the authors (see ibid., vol.27, p.1515-21, 1982) in which the authors stated that there were intra-laboratory differences between cross-sectional studies of vertebral bone mineral content in normal women as measured by dual-photon absorptiometry. The authors say that the letter by Mazers et al. provides further justification for their belief that technical problems in dual-photon absorptiometry need to be explored.