Which psychological and psychosocial constructs are important to measure in future tendinopathy clinical trials? A modified international Delphi study with expert clinician/researchers and people with tendinopathy

OBJECTIVE: to identify which psychological and psychosocial constructs to include in a core outcome set to guide future clinical trials in the tendinopathy field. DESIGN: modified International Delphi study. METHODS: In three online Delphi rounds, we presented 35 psychological and psychosocial constructs to an international panel of 38 clinician/researchers and people with tendinopathy. Using a 9-point Likert scale (1 – not important to include, 9 -critical to include), consensus for construct inclusion required ≥70% of respondents rating‘extremely critical to include’ (score ≥ 7) and ≤15% rating ‘not important to include’ (score ≤3). Consensus for exclusion required ≥70% of respondents rating ‘not important to include’ (score ≤ 3) and ≤15% of rating ‘critical to include’ (score ≥ 7). RESULTS: Thirty-six participants (95% of 38) completed round one, 90% (n=34) completed round two and 87% (n=33) completed round three. Four constructs were deemed important to include as part of a core outcome set: kinesiophobia (82%, median: 8, inter quartile range (IQR): 1.0), pain beliefs (76%, median: -7, IQR: 1.0), pain related self-efficacy (71% median: 7, IQR: 2.0) and fear avoidance beliefs (73%, median: -7, IQR: 1.0). Six constructs were deemed not important to include: perceived injustice (82%), individual attitudes of family members (74%), social isolation and loneliness (73%), job satisfaction (73%), coping (70%) and educational attainment (70%). Clinician/researchers and people with tendinopathy reached consensus that kinesiophobia, pain beliefs, pain self-efficacy and fear avoidance beliefs were important psychological constructs to measure in tendinopathy clinical trials.