Linear regression effect of R on h-index in 2015, separated by field.

Restricted to the 233,798 authors with Np ≥ 30 and I1 ≥ 4 in 2015. The standardized effect is obtained by dividing the coefficient by the standard deviation of h in 2015 for each field. Results are shown unadjusted, and adjusted for total publications, average number of co-authors, first year of publication, US-based or not, and gender (male or female).