“…Across‐administration test quality control may include the evaluation of the fluctuation of score summary statistics, population composition and background changes, test content evolution and difficulty shift, equating errors and scale drift, and the stability of psychometric properties such as reliability and validity. Various methods and procedures have been proposed for this purpose, such as time series analysis (Li, Li, & von Davier, ), harmonic regression (Lee & Haberman, ), linear mixed effects modeling (Lee, Liu, & von Davier, ), Shewhart control charts (see a brief description in von Davier, ), hidden Markov modeling (Lee & von Davier, ), and multilevel analysis (Wei, ; Wei & Qu, ).…”