# Reliability of a New Portable Dynamometer for Assessing Hip and Lower Limb Strength
## 3 Results
### Inter-Session Reliability  
Results of inter-session reliability analysis are shown in Table 4. Again, the peak torque values of all bilateral tests had very high inter-session reliability. Specifically, no systematic bias, very high to excellent test-retest reliability (ICC2,k > 0.85), and low within-individual variation (CV \(<\) 9%) was shown for bilateral HADD (ICC2,k = 0.96-0.97; CV = 1.9-2.3%), HABD (ICC2,k = 0.94; CV = 2.7%), HIR (ICC2,k = 0.86-0.87; CV = 5.5-6.7%), HER (ICC2,k = 0.94-0.95; CV = 2.2-2.4%). The exception was NHE, which also had very high test-retest reliability and low within-individual variation (ICC2,k = 0.86-0.88; CV = 5.4-5.9%) but with systematic bias present for average peak torque (\(d\) = 0.29).  
\begin{table}
\begin{tabular}{l c c c c c c c c c} \hline \hline \multirow{2}{*}{**Parameter**} & \multirow{2}{*}{**S1 Mean (SD)**} & \multirow{2}{*}{**S1 95\% CI**} & \multirow{2}{*}{**S2 Mean (SD)**} & \multirow{2}{*}{**S2 95\% CI**} & \multirow{2}{*}{**\% CV**} & \multirow{2}{*}{**ICC2,k**} & \multicolumn{3}{c}{**Bias**} \\ \cline{5-10}  & & & & & & & **F** & **sig** & \(d\)** \\ \hline ADD:ABD UNI R & 105.74 (24.58) & 95.91–115.57 & 110.29 (30) & 98.03–122.55 & 19.3 & 0.55 & 0.17 & 0.68 & 0.17 \\ ADD:ABD UNI L & 112.13 (24.5) & 102.33–121.93 & 114.39 (27.85) & 103.01–125.77 & 12.6 & 0.65 & 0.06 & 0.81 & 0.09 \\ ADD:ABD BI R & 102.03 (17.51) & 93.32–110.4 & 101.83 (15.74) & 94.09–108.94 & 9.4 & 0.71 & 0.00 & 0.95 & 0.01 \\ ADD:ABD BI L & 103.19 (19.66) & 92.89–111.99 & 102.63 (15.86) & 94.77–109.79 & 11.9 & 0.66 & 0.01 & 0.94 & 0.03 \\ I:RE UNI R & 97.08 (24.47) & 86.85–107.31 & 102.42 (25.74) & 92.1–112.7 & 22.5 & 0.39 & 1.08 & 0.31 & 0.21 \\ I:RE UNI L & 95.14 (28.38) & 83.79–106.49 & 108.36 (25.86) & 98.01–118.71 & 11.3 & 0.78 & 9.95 & 0.00 & 0.49 \\ I:RE BI R & 125.85 (32.20) & 109.87–138.97 & 128.15 (27.68) & 114.67–141.09 & 9.9 & 0.76 & 0.18 & 0.68 & 0.08 \\ I:RE BI L & 122.04 (26.94) & 109.79–133.06 & 123.44 (26.37) & 111.78–135.91 & 8.1 & 0.83 & 0.11 & 0.74 & 0.05 \\ FLEXT UNI R & 74.8 (15.67) & 68.25–81.35 & 78.53 (17.71) & 71.44–85.62 & 7.5 & 0.8 & 0.95 & 0.34 & 0.22 \\ FLX:EXT UNI L & 74.89 (14.43) & 68.86–80.92 & 81.1 (16.17) & 74.63–87.57 & 8.1 & 0.75 & 4.68 & 0.04 & 0.40 \\ \hline \hline ADD = addduction, ABD = abduction; IR = internal rotation; ER = external rotation; EXT = extension; FLX = flexion; UNI = ratio, calculated from unilateral contractions; BI = ratio, calculated from bilateral contractions; R = right leg; L = left leg; S1 = session 1; S2 = session 2; CI = confidence interval; CV = coefficient of variance; ICC = interclass coefficient; \(d\) = effect size—Cohen’s \(d\). & & & & & \\ \hline \hline \end{tabular}
\end{table}
Table 3: Intra-session reliability-peak torque hip agonist:antagonist ratio (%).  
ranging from 0.44 to 0.68, CVs ranging from 5.7% to 7.2%, and with significant systematic bias for one side (\(F\) = 5.51-5.84, p = 0.02-0.03; \(d\) = 0.46-0.51).  
The calculated agonist:antagonist ratios in bilateral strength tests had no systematic bias, with very high inter-session reliability for HADD:HABD ratios (ICC2,k = 0.89-0.92, CV = 3.2-4.4%) and good inter-session reliability for HIR:HER ratios (ICC2,k = 0.58-0.67; CV = 12.5-16.2%) (Table 5). For unilateral strength tests, the calculated agonist:antagonist ratios had lower inter-session reliability. Significant systematic bias was observed for unilateral left HFLX:HEXT ratios (\(d\) = 0.99), with ICC coefficients ranging from low (0.30 for the left HADD:HABD ratio) to high (0.78 for the right HIR:HER ratio) and CVs ranging from moderate (11.9% for the right HIR:HER ratio) to high (25.6% for the left HADD:HABD ratio).