. 2021 Jan 26;21(3):808. doi: 10.3390/s21030808

Table 8.

Evaluation metrics (domain) and reported results for the analyzed studies. Legend: ▼ significant decrease; ▲ significant increase; ▼ non-significant decrease; ▲ non-significant increase; ∼ unchanged; avg, average; ♂ male; ♀ female; 🟉 subjects with low-back pain.

#	Device	Subj.	Tasks	(Domain) Evaluation Metrics and Criteria
1	SPEXOR	19 ♂	Lifting; Repetitive bending Standing and walking Static forward bending	(Subjective) M-SFS ▼ $7 %$
2	SPEXOR	11 ♂	Static forward bending; Lifting Repetitive lifting; Kneeling Load carrying; Sit to stand (StS)	(Muscular) `LT` ▼ $10 %$ , `IL` ▼ $16 %$ , `LL` ▼ $16 %$ , `EO` ∼, `RA` ∼ (Functional) Kinematics ∼ (Metabolic) Met. cost ▼ 18% (Force/torque) Joint work ▼
4	SPEXOR	10 ♂	Static forward bending Load lifting	(Muscular) `IL`-`LL` ∼, `RA`-`EO` ∼. (Force/torque) L5-S1 Fc ▼ $21 %$ , L5-S1 Mfe ▼ $8.1 %$ (Functional) $α$ -Hip ▼ $17 %$ (Muscular) ▼ $22 %$ (avg.), (Force/torque) L5-S1 Fc ▼ $14 %$ (Functional) $α$ -Hip ∼
5	SPEXOR	🟉7 ♂ 🟉7 ♀	Static forward bending; Lifting Load carrying; Kneeling; Walking Sit to stand; Stair climbing	(Functional) Posture holding time: ▲ $12.29 %$ for SFB; ▲ $8.66 %$ for StS; ▲ $7.26 %$ for climbing (Subjective) Discomfort: ▼ for SFB and sit to stand
15	SPEXOR	🟉13 ♂ 11 ♂	Static forward bending; Lifting Load carrying; Kneeling; Walking Sit to stand; Stair climbing	(Functional) Lifts/2-min ▲ $12.5 %$ ; Posture holding time ▲ $35.5 %$ for SFB; Walk dist. ▼ $7.7 %$ Perf. time ▲ $8.2 %$ for stair climbing. (Subjective) PTD ▼ for SFB, lifting, kneeling
3	Laevo	11	Lifting	(Muscular) ▼ $8 %$ (avg.) (Force/torque) L5-S1 Fc ▼ $6 %$ (Functional) Peak $\dot{α}$ -Hip ▼ $17 %$
7	BackX AC Laevo	9 ♂ 9 ♀	Static forward bending	(Musc.) `TES-IL` ▼ $46 %$ , ▼ $35 %$ (avg.) (Func.) Perf. time ▲ $6.9 %$ (Subjective) BORG ▲ $75 %$ (Musc.) `TES-IL` ▼ $22.5 %$ , ▼ $13 %$ (avg.) (Func.) Perf. time ▲ $7.6 %$ (Subjective)
8	Laevo	18 ♂	Static forward bending Walking; Sitting; Squatting	(Metabolic) For lifting: Met. cost ▼ $16.5 %$ . (Subjective) PTD ▼ for SFB. For load carrying: Met. cost ▲ 14.5% PTD ▲ for walking, sitting, squatting
9	Laevo	11 ♂	Static forward bending	(Muscular) `IL` ▼, `EO` ▲ $10 %$ +, `IO` ▲ $10 %$ +, `RA` ∼, `LL` ∼ (Force/torque) L5-S1 Mfe ▼ (Functional) $α$ -Hip ▼
12	Laevo	18 ♂	Static forward bending; Lifting Load carrying; Sit to stand	(Functional) Perf. time ▲ for SFB (Subjective) PTD ▼ for SFB PTD ▲ for StS and walking. LD ▼ for SFB (low back). LD ▲ for SFB (chest)
14	Laevo	9 ♂ 9 ♀	Static forward bending Static holding task (SHT)	(Muscular) For SFB: `BF` ▼ $20 %$ , `TA` ▼ $44 %$ , (Functional) $α$ -Hip ▲ $15.9 %$ `ESL`▼ $35 %$ , `ESI`▼ $38 %$ (Subjective) LD ▼ (low back) For SHT: `BF` ▼ $24 %$ , `TA` ▼ $50 %$ LD ▲ (chest) `ESL`▼ $37 %$ , `ESI`▼ $44 %$
18	Laevo	30 ♂	Static forward bending Load lifting	(Subjective) LPD (over time): ▼ $40 %$ (low back), ▼ $50 %$ (wrist), ▲ $50 %$ (chest) UMUX (over time): ∼ Donning/doffing, ▼ Task perf. Intention to use(over time) ▼ 25%
10	Robo-Mate	10 ♂	Load lifting	(Muscular) `IL-LL` ▼ $19 %$ (Force/torque) L5-S1 Fc ▼ $17.8 %$ , L5-S1 Mfe ▼ (Functional) $α$ -Hip ▼ $15.9 %$ , $\dot{α}$ -Hip ▼ $25 %$
11	HAL	14 ♂	Lifting	(Muscular) Muscle activity: `TES` ▼ $11.5 %$ , `LES`▼ $4.5 %$ , `QF`▲ $15 %$ (Subjective) BORG ∼ iEMG: `TES` ▼ $19.55 %$ , `LES`▼ $11.4 %$
20	HAL	11 ♂ 7 ♀	Stoop load lifting	(Functional) Number of lifts ▲ $45 %$ ; Lifting time ▲ $44 %$ (Subjective) ▼ $25 %$ Perceived lumbar fatigue
13	‘Active indus-trial exo’	12 ♂	lifting; Lowering	(Muscular) `RA` ∼, `BF`▼ $5 %$ , `LES`▼ $12 %$ (w/7.5 kg) (Subjective) BORG ▼ $9.5 %$ (w/7.5 kg) `LES` ▼ $15 %$ (w/15 kg) BORG ▼ $11.4 %$ (w/15 kg) SUS > 60
16	MeBot-EXO	7 ♂	Semi-squat load lifting	(Muscular) `TES` ▼ $42.5 %$ , `LES`▼ $38.5 %$ (Metabolic) Met. cost ▼ $18 %$
17	Lower-limb exo	5 ♂	Lifting; Load carrying	(Muscular) For lifting: `VI` ▼ $40.8 %$ , `GA`▼ $45.3 %$ . For carrying: `VI`▼ $45.3 %$ , `GA`▼ $36.1 %$
19	LAD	1 ♂	Lifting	(Muscular) `RA` ▼, `ES`▼
21	‘Passive spine exoskeleton’	3 ♂	Dynamic bending Static forward bending	Muscular) `TES` ▼ $54 %$ , `LES`▼ $24 %$ (Functional) Kinematics ∼
22	‘Lower extremity exoskeleton’	5 ♂ 1 ♀	Lifting	(Muscular) `ES` ▼ $54 %$ (Force/torque) [l]L5-S1 Fc ▼ $60.3 %$ (w/4.5 kg payload) L5-S1 Fc ▼ $43 %$ (w/13.6 kg payload
23	APO	5 ♂	Lifting; Lowering	(Muscular) iEMG (average iEMG): `TES` ▼ $6 %$ (▼ $34.7 %$ ); `LES`▼ $15.9 %$ (▼ $33 %$ ); `BF`▼ $27.4 %$ (▲ $7.1 %$ ) `ESI` ▼ $3.65 %$ (▼ $8.9 %$ ) `RF`▲ $33.7 %$ (▲ $40.1 %$ ) (Functional) Time for trunk extension ▼ $19.1 %$

Abbreviations: Fc, compression force; LD, local discomfort; LPD, local perceived discomfort; Mfe, flexion-extension moment; M-SFS, Modified Spinal Function Sort; PTD, perceived task difficulty; SFB, static forward bending; SUS, system usability scale; UMUX, Usability Metric for User Experience. Muscles: BF, biceps femoris; ES, erector spinae; ESI, erector spinae iliocostalis; ESL, erector spinae longissimus; GA, gastrocnemius; LES, lumbar erector spinae; QF, quadriceps femoris; RA, rectus abdominis; RF, rectus femoris; TA, trapezius pars ascendens; TES, thoracic erector spinae; VI, vastus intermedialis.