Table 1.

Study Sample Descriptions

	Sample A: Cross-sectional Survey	Sample B: Score Linking Survey	Sample C: Pain observations Study
Recruitment	Participants from previous UW or UNC studies, patients at UW Pain Clinic, flyers at other Seattle clinics, and web posting on UW website	Random subset of PwP who participated in either Sample A or Sample C and indicated interest in participating in future research studies	Participants from Sample A, clinician referrals, advertisements, flyers, web postings
Inclusion/Exclusion Criteria
PwP	Self-report of at least one of 3 target clinical conditions; ≥ 18 years of age; read/understand English; SO who spends ≥ 7 hours/week with them and willing to participate; average pain in past week ≥ 3 (0–10 scale), persisting ≥ 6 months; and able to walk (with or without assistive device). Individuals who used wheelchairs most or all of the time were excluded because use of a wheelchair could impact how and what pain behaviors are displayed.	Same as for Sample A except no SO reporting was required.	Same as for Sample A except that self-reported average 7 day pain score required to be ≥ 3 (0–10 scale), and pain reported to affect walking, sitting or reclining. Participants were not required to have a SO.
SOs	Nominated by PwP and willing to participate.	n/a	n/a
Number of PwP and SOs by Clnical Condition
Arthritis	N= 226 PwP, N=206 SOs	N=161 PWP	N=26 PwP
Back Pain	N=225 PwP, N=209 SOs	N=154 PWP	N=30 PwP
Multiple Sclerosis	N=210 PwP, N=203 SOs	N=158 PWP	N=30 PwP
Data collected
PwP	Demographics, clinical status, candidate PaB-SR items, other pain measures	Subset of PaB-SR items and PROMIS items that had the same item content but different response scales.	Demographics, clinical status, current pain (0–10), candidate PaB-SR items, other pain measures
SOs	Demographics, parallel items to candidate PaB-SR items, UAB Pain Behavior Scale	n/a	n/a
How data were used	Item-level validity, score level validity	Align PaB-SR scores to PROMIS metric	Item-level validity, score level validity

UW = University of Washington, Seattle; UNC = University of North Carolina, Chapel Hill; PwP = participants with pain; SOs = significant others; PaB-SR = Pain Behaviors Self Report