Measurements of journal use: an analysis of the correlations between three methods

Rapid journal price increases have made essential that libraries have reliable and efficient measures of the importance of individual journals to local clientele. Three key measures are in-house use, circulation, and citation by faculty. This paper examines the correlations between these three measures at an academic health sciences library. Data were gathered from 1992 to 1994 using each of the three methods. Each set of data was compared with the other two, and for each pair of data sets both Spearman Rank Order and Pearson Product-Moment correlation coefficients were calculated to examine the degree of correlation between the two sets. All of the correlation coefficients were positive and statistically significant (P < 0.0001). This information suggests that if gathering many types of use data is impractical, one method may be used with the confidence that it correlates with other types of use. Visual inspection of the data confirms this with one exception: many clinical review titles tend to have a low local citation rate but high in-house use and circulation rates, suggesting that these are being used for educational and clinical purposes but not for research.