Measurements of journal use: an analysis of the correlations between threemethods

Rapid journal price increases have made essential that libraries have relia ble and efficient measures of the importance of individual journals to loca l clientele. Three key measures are in-house use, circulation, and citation by faculty. This paper examines the correlations between these three measu res 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 t he other two, and for each pair of data sets both Spearman Rank Order and P earson Product-Moment correlation coefficients were calculated to examine t he degree of correlation between the two sets. All of the correlation coeff icients were positive and statistically significant (P < 0.0001). This info rmation suggests that if gathering many types of use data is impractical, o ne method may be used with the confidence that it correlates with other typ es 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 f or educational and clinical purposes but not for research.