Table 2 Overview of reliability, validity and measurement error for static balance assessments for assessments used to monitor movement changes following a concussion
| Â | Time taken | Equipment | Test procedure | Outcome variable | Reliability | Validity | Measurement error | Optimal conditions |
|---|---|---|---|---|---|---|---|---|
Non-instrumented static assessments | ||||||||
Balance error scoring system (BESS) | ||||||||
2 trials, 4 conditions: 5 min | Stopwatch Foam pad | Double leg, single leg and tandem stance on firm surface and foam Number of errors each 30-s stance recorded | Number of errors | r = 0.41 to 0.94 Inter-tester: r = 0.20–0.96 | Sens = 0.23 to 0.60 Spec = 0.50 to 0.92 AUC = 0.51 to 0.63 | MDC test–retest = 7.3 errors MDC inter-tester = 9.4 errors | 3 examiners, minimum of 2 trials on 4 conditions (excluding double leg stances) | |
Modified balance error scoring system (mBESS) | ||||||||
 ~ 2–5-min | Stopwatch | Double leg, single leg, tandem stance on firm surface only Number of errors each 30-s stance recorded | Number of errors | r = 0.02–0.88 Inter-tester: r = 0.80–0.83 | Sens = 0.05–0.71 Spec = 0.0.63–0.85 AUC = 0.54–0.72 Between-group differences: p =  < 0.001–0.23 | – | Minimum of 2 trials Familiarisation required for children | |
Single leg stance (SLS) | ||||||||
 ~ 2–5-min | Stopwatch | Errors recorded in 30-s stance period | Number of errors | r = 0.85 | – | – | Most participants reached 30-s cut off easily | |
Modified clinical test of sensory interaction in balance (MCTSIB) | ||||||||
[56] |  ~ 5–10-min | NA | Double leg stance; stable surface eyes open, stable surface eyes closed, unstable surface eyes open, unstable surface eyes closed | Number of errors | – | Sens = 0.37 Spec = 0.88 | – | Poor sensitivity approximately 2 weeks post-concussion |
Paediatric clinical test of sensory interaction in balance (PCTSIB) | ||||||||
[56] |  ~ 5–10-min | NA | Double leg stance; stable surface eyes open, stable surface eyes closed, unstable surface eyes open, unstable surface eyes closed | Number of errors | – | Between-group differences: p = 0.46–0.49 | – |  |
Instrumented static assessments | ||||||||
Instrumented balance error scoring system | ||||||||
 ~ 5-min | Force plate or IMU | BESS performed on force plate (foam pad placed on plate) | Number of errors, COP or COM displacement | r = 0.88–0.89 | Sens = 0.38–0.0.94 Spec = 1 AUC = 0.70 | SEM = 0.00–0.45 | Perform in first month post-concussion to maximise sensitivity | |
Instrumented modified balance error scoring system | ||||||||
 ~ 2–5-min | Force plate or IMU | MBESS on force plate or with IMU | Number of errors, COP or COM displacement | Force plate: r = 0.69–0.77 Smartphone: r = 0.66–0.75 | Sens = 0.42–0.92 Spec = 0.76 -1.00 AUC = 0.74–0.91 | – |  | |
Instrumented single leg stance (instrumented SLS) | ||||||||
[64] |  ~ 2–5-min | Force plate | Measure of COP on force plate Eyes open and eyes closed conditions | Number of errors, COP displacement | r = 0.58–0.88 |  | SEM = 0.41–2.97 | Eyes closed condition displayed better reliability |
Balance accelerometry measure (BAM) | ||||||||
 ~ 5–10-min | IMU, smartglasses, or smartphone | 6 stances: firm surface—double leg eyes open, double leg eyes closed, tandem eyes open, tandem eyes closed Foam surface—double leg eyes open, double leg eyes closed Number of errors each 45-s recorded | Number of errors, COM displacement | r = 0.28–0.86 | AUC < 2 weeks = 0.74–0.77 AUC > 2 weeks = 0.67–0.68 | - | Perform within 2 weeks post-concussion | |
Balance tracking system | ||||||||
 ~ 2-min | Force plate | 4 × 20-s trials: 1 familiarisation and 3 recorded. Participant standing on force plate with eyes closed and hands on hips COP recorded | COP displacement | – | Sens = 0.64 | – | Baseline scores better for comparison | |
SWAY balance | ||||||||
[68] |  ~ 2–5-min | Smartphone | 5 × 10-s stances: bipedal, tandem (R), tandem (L), single leg (R), single leg (L) on firm surface with eyes closed SWAY scores calculated | COM displacement | r = 0.47–0.86 | – | SEM = 5.77–7.56 | 3 sessions Mobile held on sternum |
Sensory organisation test (SOT) | ||||||||
 ~ 10–20-min | SOT laboratory equipment | 6 conditions: stance eyes open, eyes closed, eyes open with visual interference, eyes open with surface interference, eyes closed with surface interference, eyes open with visual and surface interference Each lasting 20-s | COP displacement | r = 0.3–0.72 | Sens = 0.13–0.73 Spec = 0.85–0.95 AUC = 0.79 | SEM = 4.92–5.00 |  | |
Physiological vibration acceleration (Phybrata) System | ||||||||
[46] |  ~ 2-min | IMU | 20-s stance with eyes open, and then eyes closed | COM displacement | – | Sens = 0.92 Spec = 0.94 AUC = 0.98 | – |  |
Instrumented modified clinical test of sensory interaction in balance (MCTSIB) | ||||||||
[73] |  ~ 5–10-min | Force plate | Double leg stance; stable surface eyes open, stable surface eyes closed, unstable surface eyes open, unstable surface eyes closed | Number of errors, COP displacement | – | Sens = 0.37 Spec = 0.88 | – |  |
Virtual reality balance | ||||||||
 ~ 10-min | Force plate Virtual reality system | Standing in tandem stance, hands on hips. Participant placed in harness and positioned in 3D virtual reality room. 10 trials performed, 1 with the room still, 9 with it moving. Each trial lasted 30-s | COP displacement | – | Sens = 0.86 Spec = 0.88 AUC = 86 Between-group differences: p = 0.006- < 0.001 | – | 10 trials–1 trial with still room, 9 trials with rotating room | |