RESUMEN
The study was carried out at Tri-Service General Hospital and Mackay General Hospital. The sample population of patient was totally 120. According to their body weight and height, they were divided into six groups with various sizes, i.e. normal, over and under-weighted adults, followed by sex differences. After computer tomographic scanning results from patients' body back, the relative acupuncture loci should be measured through their anatomical position, then the distance between surface of body back and thoracic pleura could be defined as its safety depth. For each locus of the groups, the mean and its confident interval could be found. The analysis of variance (ANOVA), t-test, and multiple regression were also calculated by means of computer. The results showed that there were no significant differences on body back loci within sex differences, but for different body sizes, there appeared statistically significant differences for each locus, (P less than 0.01), so the safety depth for each back locus have actually been proved. Not only these data provided more useful information for clinical practices, but also our standard safety depth for each loci on back can then be established.