scopus_compare_topics: Compare publication trends across topics

In scopusflow: A Reproducible Workflow Layer for 'Scopus' Bibliographic Searches

Compare publication trends across topics

Description

Compares how often a set of comparison topics co-occur with a reference topic over time. For each year and each comparison term, the number of records matching the reference combined with that term is expressed as a percentage of the records matching the reference alone. This reveals which sub-topics are growing or shrinking within a literature.

Usage

scopus_compare_topics(
  reference_query,
  comparison_terms,
  years,
  field = NULL,
  view = c("STANDARD", "COMPLETE"),
  api_key = NULL,
  inst_token = NULL,
  verbose = FALSE
)

Arguments

reference_query	Character scalar. The reference topic that anchors the comparison (for example "language learning").
comparison_terms	Character vector of topics to compare against the reference (for example c("effect size", "Bayesian")). Each is combined with the reference using a logical AND.
years	Integer vector of publication years to span (for example 2015:2020).
field	Optional 'Scopus' field tag applied to every component of every query (see scopus_plan()).
view	Either "STANDARD" or "COMPLETE".
api_key, inst_token	Optional credentials (see scopus_has_key()).
verbose	Logical. When TRUE, progress is reported.

Value

A tibble of class scopus_comparison with the columns query (the full query used), query_type ("reference" or "comparison"), abridged_query (the topic label for plotting), year, n (records that year), reference_n (reference records that year), comparison_percentage (100 * n / reference_n, or NA when reference_n is 0) and average_comparison_percentage (the same ratio computed on period totals). Comparison rows are sorted by descending average percentage.

API access

This performs one count request per term per year, so it requires a valid API key and internet access. The API access section of scopus_count() gives the details. A modest number of terms and years keeps the call within quota.

See Also

plot_scopus_comparison() to visualise the result.

Examples

cmp <- scopus_compare_topics(
  reference_query = "deep learning",
  comparison_terms = c("computer vision", "drug discovery", "medical imaging"),
  years = 2015:2022,
  field = "TITLE-ABS-KEY"
)
cmp

scopusflow documentation built on June 20, 2026, 5:06 p.m.