Check the exact prior-publication policy
Identify whether the earlier output was an abstract, poster, proceedings article or full archival paper. Read the journal’s current instructions for that situation. IEEE recognizes the progression from conference findings to a more developed journal contribution, but individual publications can impose additional requirements.
Make the new contribution explicit
Prepare a comparison table listing the earlier findings and the additional theory, evidence, analysis or validation in the proposed article. Added length is not the same as added knowledge. The research team should be able to explain why the journal reader needs the extended work.
Disclose and cite the earlier work
Cite the conference paper where relevant and describe the relationship in the cover letter and submission fields required by the journal. Supply the earlier version if requested. Do not hide overlap by changing the title or rewriting equivalent sentences.
Review permissions and consistency
Check the rights for any reused tables, figures or text. Reconcile values that appear in both versions and explain differences caused by new data or analyses. Retain the original paper and a record of changes so coauthors can review the full relationship.
Build a journal-specific submission package
Update the abstract, structure and supporting files for the chosen article category. Agree authorship based on actual contributions, obtain final approval and disclose relevant assistance. No universal percentage of new words guarantees that an extension is acceptable; the journal evaluates substance and policy compliance.