Some physics students express concern about their speed on tasks compared to peers. How does this relate to their course grades?

We have previously found that in introductory physics courses, among students with the same accuracy on math skills, students who are faster on math earn higher grades on physics exams. Cognitive (e.g. skill fluency) and non-cognitive (e.g. psychological) mechanisms may play a role in explaining this finding. To investigate some potential non-cognitive mechanisms, we surveyed N~500 algebra-based intro physics students on psychological factors including Self-Efficacy (SE), concern about speed compared to peers ('Speed Comparison Concern' (SCC)), and concern about accuracy compared to peers ('Accuracy Comparison Concern' (ACC)). Though all three of these factors are correlated with each other and with physics exam grades, only SCC is associated with student speed on math skills after controlling for accuracy on math. Mediation models support the argument that SCC plays a role in explaining why faster students on math do better on physics exams. Open responses from students improve the validity of the SCC construct, particularly discriminate validity compared to ACC and SE. Further, these responses provide potential reasons for why students are concerned about their speed, how it may affect their exam performance, and possible instructional strategies to mitigate this concern.