An investigation of differential item functioning using SIBTEST for multi-categorically scored performance assessment

The National Board for Professional Teaching Standards (NBPTS or National Board) established, in 1987, a performance-based advanced teacher certification system for all teachers, regardless of cultural background or teaching environment, to appropriately demonstrate their content and pedagogical knowledge. The National Board has not subjected their assessments to a sophisticated statistical procedure or detection method for uncovering bias that will allow for the investigation of differential performance by exercise across racial groups. The purpose of this research was to apply Simultaneous Item Bias (SIBTEST) statistical procedure to investigate differential item functioning (DIF) by examining comparable groups of White and African American candidate performances on NBPTS exercises.;The SIBTEST statistical procedure for investigating DIF for polytomously scored items was applied to scores from the NBPTS assessments for Early Childhood/Generalist (ECGEN) and Middle Childhood/Generalist (MCGEN) certificates from the years 1996 to 2000. The results of the SIBTEST analysis indicated that seven exercises were found to exhibit DIF, across the ECGEN and MCGEN certificates. Five exercises were found to exhibit DIF favoring African American teacher candidates. This finding suggests that the African American candidates performed better when the exercises relied on 'knowledge of students' and 'classroom community building'.;The study also applied the SIBTEST to investigate candidate performance by subtest or exercise type. The results of analysis for the assessments center subtest indicate that the White candidates outperformed their equally able or matched African American counterparts. This finding suggests that the African American candidates performed less well when they were required to respond to simulated classroom situations. Overall, the study provided some insight into how candidates' exercise and subtest performance is affected by race.