  Recently, the integrated impact indicator (I3) indicator was introduced where
citations are weighted in accordance with the percentile rank class of each
publication in a set of publications. I3 can also be used as a field-normalized
indicator. Field-normalization is common practice in bibliometrics, especially
when institutions and countries are compared. Publication and citation
practices are so different among fields that citation impact is normalized for
cross-field comparisons. In this study, we test the ability of the indicator to
discriminate between quality levels of papers as defined by Faculty members at
F1000Prime. F1000Prime is a post-publication peer review system for assessing
papers in the biomedical area. Thus, we test the convergent validity of I3 (in
this study, we test I3/N - the size-independent variant of I3 where I3 is
divided by the number of papers) using assessments by peers as baseline and
compare its validity with several other (field-normalized) indicators: the
mean-normalized citation score (MNCS), relative-citation ratio (RCR), citation
score normalized by cited references (CSNCR), characteristic scores and scales
(CSS), source-normalized citation score (SNCS), citation percentile, and
proportion of papers which belong to the x% most frequently cited papers (PPtop
x%). The results show that the PPtop 1% indicator discriminates best among
different quality levels. I3 performs similar as (slightly better than) most of
the other field-normalized indicators. Thus, the results point out that the
indicator could be a valuable alternative to other indicators in bibliometrics.
