Item	Reason for removal
PR1—I was interested in the issue(s) being researched in the project	Low inter‐item correlations with 21 items between ‐0.22 and 0.19; average = 0.15
PR3—The number of patient partners on the research project team seemed appropriate	Low inter‐item correlations with 10 items between ‐13 and 0.18; average = 0.23
PR4—I understood the objective(s) of the project	Low inter‐item correlations with 11 items between ‐0.09 and 0.19; average = 0.26
PR5—I agreed with the objective(s) of the project	Low inter‐item correlation with 15 items between ‐0.13 and 0.19; average = 0.21
PR6—I understood how I could contribute to the project	Low inter‐item correlations with 15 items between ‐0.13 and 0.19; average = 0.21
PR7—I received sufficient explanation about the project	Low inter‐item correlations with 20 items between ‐0.15 and 0.18; average = 0.15
PR8—I understood my ethical responsibilities for the project	Low inter‐item correlations with 9 items between ‐0.19 and 0.11; average = 0.24
CN2—My preferences for meetings (such as time, duration, location, and format) were considered when planning meetings	Does not fit with Rasch derived construct (fit residual = 3.24). [Rasch Analysis]
CT3—I shared my knowledge within the project team	High residual correlation (>0.4) – too similar to CT1 and CN4 [Rasch Analysis]
T1—Throughout the project, I felt accepted as a member of the research project team	Too high correlations (≥0.78) with T3 and T5
T3—My interactions within the research project team were positive	High residual correlations with other items [Rasch Analysis]
T4—There was mutual respect among the research project team members	Too high correlation (>0.8) with T5
SU3—I was offered sufficient reimbursement for my out‐of‐pocket expenses (such as childcare, parking, and travel) related to the project activities	Low inter‐item correlation (<0.20) with 4 items; average = 0.30
FV2—The research project team was open to receiving my views	Relatively high correlation (≥0.74) with T4 and FV1
BE3—I saw how my contributions could benefit others	Low inter‐item correlation with 10 items between ‐0.11 and 0.18; average = 0.26