This paper highlights the importance of developing high-quality items in Item Response Theory (IRT)-based educational assessments and proposes an efficient item validation method utilizing Item-Writing Flaw (IWF) analysis, replacing the traditional, resource-intensive pretesting method. We performed automated IWF analysis on 7,126 multiple-choice STEM items based on 19 criteria and analyzed their correlations with IRT difficulty and discrimination indices. The results revealed significant correlations between the number of IWFs and IRT difficulty and discrimination indices, particularly in the life/earth sciences and physical sciences. Furthermore, we found that specific IWF criteria (e.g., negative vocabulary use vs. unrealistic incorrect answer options) had varying effects on item quality and difficulty. These findings suggest that automated IWF analysis can complement existing validation methods as an efficient prescreening method for items, particularly for selecting low-difficulty items. However, we also highlight the limitations of domain-specific evaluation criteria and algorithms, as well as the need for further research that considers domain-specific characteristics.