摘要:Among the Journal Citation Reports data of 1980, the number of citing items, the number of cited items, the number of self-citing items, the impact factor, the decay index, the immediacy index, and the number of papers are compared in the 47 subject fields of biological sciences and medicine. The results are: 1. The number of cited items of a journal corresponds to the number of citing items. 2. The values of the number of cited items divided by the number of citing items are relatively constant. On the other hand, the values of the impact factor fluctuate among the subject fields. 3. The values of the decay index are relatively constant, while those of the immediacy index fluctuate among the subject fields.