Comparison of several author indices for gauging academic productivity

Background Many author indices exist to gauge academic productivity. Several of these indices are calculated based upon an author's scholarly publication record, but the measurement methodology to calculate each index varies considerably, and the precise function being used, as well as the end result, is often complex and difficult to assess. Method Two straightforward methods to weigh author productivity from the publication and citation record were evaluated as possible means for providing a clearer assessment of scholarly activity. The author characteristic index (termed c-index) assigns author rank for each publication based upon author position. The characteristic prime (c') -index normalizes author rank from author position, so that the total weight per publication is unity. The top 10 scholars with keyword 'celiac disease' in the Google Scholar database were then assessed using these metrics. Rankings according to total number of publications, h-index, and c- and c'-indices were compared, then tabulated along with total papers included for assessment, and mean values per paper for author position, number of authors, citations, and year of publication. Results The order of the top ten authors with keyword 'celiac disease' varied substantially depending upon whether the h-index, c-index, or c'-index was used as a gauge. The characteristic indices assign credit to authors according to their position in an author list. The affiliated metrics provided a more complete picture of scholarly activity. Conclusions Academic achievement by scholars, based upon quantitative publication characteristics, has recently become of interest for evaluating job candidates, for determining work performance, and for bestowing awards and honors. The characteristic indices as described herein are readily calculated and interpreted, and may improve the assessment of scholarly activity.