impact factor
nounPronunciation: /ˈɪmpækt ˈfæktər/
Also written as: IF
A metric measuring the average number of citations received by articles published in a journal during a specific time period.
Full Definition
Impact factor is a quantitative measure of journal influence calculated by dividing the number of citations in a given year to articles published in the journal during the two preceding years by the total number of articles published in those years. Published annually by Clarivate Analytics in the Journal Citation Reports, it serves as a proxy for journal prestige and research impact. The metric influences academic career decisions, institutional rankings, and funding allocations. However, it has limitations including disciplinary variations, citation manipulation possibilities, and emphasis on short-term impact over long-term significance.
Plain English
A number that shows how often articles from a particular academic journal get cited or referenced by other researchers, indicating how influential the journal is.
In Editorial Context
A key performance indicator for journal success that influences editorial strategy, author attraction, and institutional partnerships, requiring editorial awareness of factors affecting citation patterns.
Etymology & History
Developed by Eugene Garfield to help librarians make journal subscription decisions, later became a measure of academic prestige.
Originally a practical tool for librarians, evolved into a controversial metric for evaluating research quality and academic performance.
Usage
"The editorial board discussed strategies to increase the journal's impact factor through improved peer review and author outreach."
Usage note: Should not be used as the sole measure of journal quality or research impact; context and disciplinary norms matter.
Context: journal evaluation, academic assessment, research metrics
Region: international
Style guide notes: Chicago Manual capitalizes when referring to Journal Impact Factor as proper noun. AP style uses lowercase unless part of official metric name. Many style guides require trademark attribution to Clarivate Analytics
In Context
- "The journal's five-year impact factor increased from 2.1 to 3.4 following editorial policy changes."
- "Authors should consider journal scope and audience rather than solely focusing on impact factor when selecting publication venues."
- "The editorial board discussed strategies to improve citation patterns and potentially increase the journal's impact factor."
Also known as
Don't confuse with
H-index measures individual researcher impact, while impact factor measures journal-level influence; citation count is raw numbers without normalization.
Common mistake: Using impact factor to evaluate individual articles rather than journals, comparing impact factors across different disciplines without context, confusing Journal Impact Factor with other citation metrics like h-index
Related Terms
Broader term: journal metrics
Frequently Asked Questions
How is the Journal Impact Factor calculated?
Journal Impact Factor divides the number of citations in the current year to articles published in the previous two years by the total number of citable articles published in those two years.
Why shouldn't impact factor be used to evaluate individual researchers?
Impact factor measures journal-level citation patterns, not individual article quality. Research quality varies within journals, and citation practices differ significantly across academic disciplines.
What are alternatives to impact factor for journal evaluation?
Alternative metrics include CiteScore, SCImago Journal Rank (SJR), Source Normalized Impact per Paper (SNIP), altmetrics, and discipline-specific ranking systems that provide broader evaluation contexts.
Why Test Candidates on This?
Critical for journal positioning, marketing materials, editorial strategy, and understanding author motivations when developing publication strategies and competitive analysis
Required skill level: Mid