Hey Andrew,
Very interesting project, and certainly an alarming gap you have mentioned. In your first paragraph, you have mentioned a critical point regarding screening--while screening is shown to be effective, improper completions of FITs is troublesome. This is unfortunately a very common case across empirically supported interventions/assessments especially when dealing with underprivileged or minority populations.
I am not sure if you have looked into this, but I was curious about whether stigma has to do with improper completions--do you think immigrants/non-English speaking populations may feel anxious during such assessment? I wonder if the studies you alluded to looked into that. If it is significant, I think addressing this matter is another potentially strong IS project.
As I mentioned, I think your project is very interesting and important to address this gap. This made me think about the other course we are taking--community engagement research. Who are your community partners? How did you decide on low literacy instructions (instead of text based) and reminder phone calls--were patients asked about their preferences?