Library use of public health materials: description and anaylsis.

A method is described for optimizing the efficiency of a journal collection. The method is employed to determine an optimal journal collection in public health. A citation analysis of 3,456 citations from the bibliographies of forty-four master's and doctoral dissertations from five different universities is performed. It is verified that the distribution of references to journal titles is approximately logarithmic (Bradford's Law) and that the distribution of references by year is exponential. These two parameters are combined to formulate an equation which may be used to specify a journal collection satisfying the greatest possible percent of demand. In public health, for example, a 1,500-volume library containing sixty titles could satisfy 73% of the demand for references in health related areas and 48% of the total demand for references for this particular, diverse research group. Other desirable aspects of a public health collection are also described as determined from the data.