Table 2. Construct Validity measured by correlations between assessment tools.
| Assessment tool | Studies first author (year) | Correlation with other assessment tools | Measurement property quality (using 0.5) | Methodological quality (COSMIN) |
|---|---|---|---|---|
| 10 sec ST | Yukawa [2009] (23) | JOALEMF score (r=0.84) | + | Very good |
| Nakashima [2011] (31) | JOATotal score [r2=0.30 (pre-operative), 0.17 (post-operative)]; JOAMEQ-L [r2=0.40(pre-operative), 0.44 (post-operative)] | NA | Very good | |
| 30MWT | Bohm [2017] (32) | Nurick grade (r=0.49); mJOATotal score (r=−0.44) | − | Very good |
| Nakashima [2011] (31) | JOATotal score [r2=0.19 (pre-operative), 0.18 (post-operative)]; JOAMEQ-L [r2=0.32 (pre-operative), 0.31 (post-operative)] | NA | Very good | |
| Singh [1999] (28) | Pre-operative, post-operative Nurick grade (r=0.61, 0.69) | + | Doubtful | |
| Gait analysis (eGVI) | Kalsi-ryan [2020] (5) | mJOAMDLE score (r=0.57), Velocity & mJOAMDLE (r=0.46) | +; − | Doubtful |
| Extension of knee in stance phase | Maezawa [2001] (39) | JOATotal score (r=0.54) | + | Inadequate |
| Triangle ST | Mihara [2010] (40) | Pre-operative Nurick Score (significant correlation†); mJOAMDLE Score (significant correlation†) | NA | Adequate |
| FTT | Numasawa [2012] (34) | JOALEMF Score (r=0.70); JOATotal Score (r=0.66); postoperative gain & JOALEMF Score (r=0.43) | +; +; − | Adequate |
| Enoki [2019] (38) | Nurick grade (r=−0.57); JOALEMF score (r=0.52); 30MWTwalking time (r=−0.51); 30MWnumber of steps (r=−0.49) | +; +; +; − | Adequate | |
| PROMIS-PF | Owen [2018] (24) | Baseline, 6-month follow-up; mJOATotal Score (r=0.61, 0.72) | + | Adequate |
| JOA Score | Kato [2015] (25) | JOALEMF & mJOAMDLE (r=0.93) | + | Inadequate |
| Zheng [2016] (41) | Gait parameters: double support duration (ms) (r2=0.25); step duration (ms) (r2=0.21) | NA | Doubtful | |
| Singh [2001] (37) | Nurick grade: pre-operative (r=0.59); post-operative (r=0.51) | + | Adequate | |
| mJOA-IT Score | Longo [2016] (27) | mJOA-ITTotal score correlated with Nurick (r=−0.62), mJOA-ITMDLE score & Nurick grade (r=−0.65) | + | Adequate |
| mJOA Score | Kopjar [2015] (29) | mJOATotal Score & Nurick grade (r=−0.63); 30MWT (r=−0.38); mJOAMDLE Score & Nurick grade (r=−0.68); 30MWT (r=−0.43) | +; −; +; − | Very good |
| Whitemore [2013] (26) | Nurick grade (r=−0.73) | + | Adequate |
Measurement property quality was rated based on Terwee et al.’s quality criteria assessment. Correlation (r) ≥0.50 was rated as “+” whereas correlation (r) <0.5 was rated as “−”. “+” = sufficient; “−” = insufficient; “r” = Spearman’s or Pearson’s correlation coefficient; “r2” = squared correlation coefficient from linear regression. †, correlation value not specified in article. NA, not applicable; 10 sec ST, 10 second Step test; JOALEMF, Japanese Orthopaedic Association Lower Extremity Motor function; JOATotal, Total Japanese Orthopaedic Association; JOAMEQ-L, Japanese Orthopaedic Association Cervical Myelopathy Evaluation Questionnaire Lower Limb Function 30MWT, 30-Meter Walk Test; mJOATotal, total Modified Japanese Orthopaedic; eGVI, Enhanced Gait Variability Index; mJOAMDLE, modified Japanese Orthopaedic Association Motor dysfunction of the Lower Extremity; Triangle ST, Triangle Step test; FTT, Foot tapping test; PROMIS-PF, Patient Reported Outcome Measurement Information System-Physical Function; JOA, Japanese Orthopaedic association; ms, Millisecond; mJOA-IT, modified Japanese Orthopaedic Association (Italian Translation); mJOA-ITTotal, Total modified Japanese Orthopaedic Association Score (Italian Translation); mJOA-ITMDLE, modified Japanese Orthopaedic Association (Italian Translation) Motor dysfunction of the Lower Extremity.