就整體軟體生命週期之支出而言，軟體維修成本已逐漸成為最昂貴、負荷最重的軟體支出o本研究提出假說:在系統開發期間對軟體執行軟體品質保證複核，有助於降低軟體維修成本，特別是在系統功能定義時執府軟體品保複核最見績效o本研究實證34個銀行業應用系統於系統上線前，執A于軟體品保才跡，利用調查研究方法蒐集資料，並建立多元迴歸模式，控制其他相關變數，以槍驗假說o實詮結果確認本研究所提假說o

Software maintenance is becoming the most expensive part of the software life cycle. This study attempts to examine the following research questions:
1.Does the SQA function have any impact on software maintenance cost reduction?
2. In which systems development phase does the SQA effort have the greatest impact on the reduction of software maintenance cost? Software quality assurance function's performing review in an early software development phase is theorized in this paper to be effective for reducing maintenance cost. A field study of business application systems in financial institutions confirmed the importance of SQA function's conducting early reviews， especially in the requirement definition stage.