Table 3.
Measures
| Measurement domain | Measurement tool | Time points | Research questiona/justification for use |
|---|---|---|---|
| Self-report measures | |||
| Pain and symptom interference | Current pain intensity (Item 6 of the Brief Pain Inventory) | Weeks 1, 4, 7, 11, 19 & 31 | RQ1, RQ3, RQ4, RQ5; group matching on baseline pain |
| Brief Pain Inventoryb (BPI; short form; pain intensity and interference) [42] | RQ2, RQ3, RQ4, RQ5 | ||
| Pain Detect Questionnaire [43] | RQ2, RQ3, RQ4, RQ5 | ||
| Average pain intensity (Logbook) | Weeks 1 to 11 (daily) | RQ2, RQ3 | |
| Average symptom interference (Logbook) | RQ2, RQ3 | ||
| Physical functioning | Average range of movement (Logbook) | Weeks 1 to 11 (daily) | RQ2, RQ3 |
| Edinburgh Handedness Inventory (current and change) [44] | Week 1 | RQ4, RQ5; participant characteristics | |
| Body representation | Bath CRPS Body Perception Disturbance Scale (BPDS) [45] | Weeks 1, 4, 7, 11, 19 & 31 | RQ2, RQ3, RQ4, RQ5 |
| Emotional functioning | Tampa Scale for Kinesiophobiab [46] | Weeks 1, 4, 7, 11, 19 & 31 | RQ2, RQ3, RQ4, RQ5; group matching on baseline fear of movement |
| Profile of Mood States [47] | RQ2, RQ3, RQ4, RQ5; group matching on baseline mood disturbance | ||
| Revised Life Orientation Test [48] | Week 1 | RQ4; group matching on baseline levels of optimism | |
| Treatment expectations | Patient-Centred Outcomes Questionnaire [49] | Week 1 | RQ4; group matching on expectations of treatment outcomes |
| Impression of treatment outcome | Patient’s Global Impression of Change [50] | Weeks 7, 11, 19 & 31 | RQ2, RQ3 |
| Treatment adherence | Treatment sessions (Logbook) | Weeks 4 to 6 (twice-daily) | Monitoring treatment adherence |
| Clinical assessments | |||
| CRPS diagnosis | Budapest diagnostic research criteria assessment [51] | Weeks 1, 4, 7 & 11 | Verification of CRPS diagnosis and assessment of eligibility |
| Symptom severity | CRPS severity score [52] | Weeks 1, 4, 7 & 11 | RQ1, RQ3, RQ4, RQ5; group matching on baseline symptom severity |
| Autonomic functions | Limb temperature asymmetry | Weeks 1, 4, 7 & 11 | RQ2, RQ3, RQ4, RQ5 |
| Oedema | |||
| Motor functions | Grip strength | Weeks 1, 4, 7 & 11 | RQ2, RQ3, RQ4, RQ5 |
| Δ Finger-To-Palm distance (ΔFTP) | |||
| Sensory functions | Mechanical Detection Threshold (MDT) | Weeks 1, 4, 7 & 11 | RQ2, RQ3, RQ4, RQ5 |
| Mechanical Pain Threshold (MPT) | |||
| Mechanical Allodynia | |||
| Two-Point Discrimination [53] | |||
| Computer-based tests of neuropsychological changes | |||
| Visuospatial attention | Visual Temporal Order Judgement (TOJ) task [8] | Weeks 1, 4, 7 & 11 | RQ2, RQ3, RQ4, RQ5 |
| Landmark task [54] | |||
| Greyscales task [55] | |||
| Mental representation of space | Mental Number Line Bisection task [56] | Weeks 1, 4, 7 & 11 | RQ2, RQ3, RQ4, RQ5 |
| Spatially-defined motor function | Directional Hypokinesia task [57] | Weeks 1, 4, 7 & 11 | RQ2, RQ3, RQ4, RQ5 |
| Body representation | Hand Laterality Recognition task [58] | Weeks 1, 4, 7 & 11 | RQ2, RQ3, RQ4, RQ5 |
aRQ1, effects of treatment on the primary outcome measures; RQ2, effects of treatment on the secondary outcome measures; RQ3, time course / duration of any changes; RQ4, predictors of CRPS progression over time and/or response to treatment; RQ5, baseline abnormalities in neuropsychological functions in participants with CRPS compared to pain-free controls, and their relationships with clinical signs of CRPS (only Week 1 data)
bBrief Pain Inventory interference subscale and Tampa Scale for Kinesiophobia are also considered proxy measures of physical functioning