論文被引用次數常被用為評估學術研究成果的指標，其對學術界的重要性不言可喻。為求公允，引用次數的運算宜力求正確，然而，由於提供查詢論文被引用次數之系統，因發展背景不同，系統的資料處理程序與原則有別，使得各篇論文的被引用次數在不同系統之檢索結果因而產生差異。本研究除藉由文獻探討外，選擇淡江大學工學院獲得校內研究獎助之學術論文372篇，以Science Citation Index Expanded（簡稱SCIE）與Scopus為對象，透過實際檢索，比較分析兩者計算論文被引用次數存在的現象與問題，以歸納影響因素。研究結果發現在比較SCIE與Scopus兩者的收錄範圍時，除資料種數外，應一併考量其收錄的資料類型與政策等面向。此外，其著錄參考文獻的規範不一，書目記錄品質的控管、引用與被引用文獻連結的處理機制等亦存在相異的作法，因而影響同一篇文獻卻有不同的被引用次數之檢索結果。由此可知，系統收錄資料的範圍、參考文獻著錄之完整性、書目記錄的品質以及文獻連結機制等情況，都是影響論文被引用次數計算之因素。

Citedness score is a widely accepted metric for the quality of scholarly literatures, therefore, the forming calculation and corresponsive consequence of citation counts becomes of importance for academic researchers, especially for the research assessment. However, the distinction of citedness score exists in heterogeneous information systems resulted from considerations for system construction and development, such as purpose, procedure and policy of data processing, and that would bring various meanings and impacts for citedness score. This paper aims to examine the distinctive factors and results on calculation of citedness score of scholarly literatures between Science Citation Index Expanded and Scopus by adoption of comparison as research methodology. In this empirical study, we selected 372 research papers from research grant publications of the College of Engineering at Tamkang University as research subject to test the citation counts from SCIE and Scopus simultaneously. As a consequence, one may generalize that four factors heavily impacts on the different citedness scores between SCIE and Scopus as follows: coverage of collected data, integrity of cited references, quality of citation record and citation pointer between citing and cited references.