Table 1.
Reproducibility in echocardiography among 18- and 28-month old mice
| r-Value | Mean ± SD | Mean ± SD Difference | Mean ± SD Difference, % | |||||
|---|---|---|---|---|---|---|---|---|
| Intraobserver Variability, n = 24 | ||||||||
| LVEDD, mm | 0.95 | 3.48±0.38 | −0.001±0.13 | 0.08±3.8 | ||||
| LVESD, mm | 0.90 | 1.50±0.29 | −0.02±0.14 | −1.93±9.9 | ||||
| PWTED, mm | 0.66 | 1.00±0.13 | 0.01±0.10 | 0.73±10.1 | ||||
| FS, % | 0.73 | 57.0±6.3 | 0.83±4.7 | 1.40±8.3 | ||||
| RWT, % | 0.72 | 28.1±4.6 | 0.15±3.5 | 0.65±12.3 | ||||
| HR, beats/min | 0.81 | 628±44 | 1.1±28 | 0.23±4.6 | ||||
| Interobserver Variability, n = 24 | ||||||||
| LVEDD, mm | 0.93 | 3.55±0.41 | −0.07±0.15 | −1.98±4.6 | ||||
| LVESD, mm | 0.91 | 1.53±0.34 | −0.02±0.15 | −1.22±9.4 | ||||
| PWTED, mm | 0.71 | 0.97±0.11 | 0.01±0.09 | 0.82±9.2 | ||||
| FS, % | 0.84 | 57.1±6.9 | −0.18±4.2 | 0.14±8.9 | ||||
| RWT, % | 0.79 | 27.7±4.2 | 0.90±2.9 | 2.79±10.0 | ||||
| HR, beats/min | 0.93 | 632±41 | −1.9±16 | −0.27±2.4 | ||||
| Test-Retest Variability, n = 15 | ||||||||
| LVEDD, mm | 0.99 | 3.51±0.24 | −0.002±0.03 | −0.03±0.9 | ||||
| LVESD, mm | 0.98 | 1.50±0.24 | −0.02±0.05 | −1.11±3.5 | ||||
| PWTED, mm | 0.96 | 0.97±0.09 | 0.004±0.03 | 0.37±2.9 | ||||
| FS, % | 0.98 | 57.5±6.1 | 0.67±1.4 | 1.25±2.4 | ||||
| RWT, % | 0.98 | 27.8±3.7 | 0.13±0.7 | 0.40±2.8 | ||||
| HR, beats/min | 0.20 | 632±25 | −20.2±30 | −3.23±4.8 | ||||
Data are means ± SD. The variability among the types of reproducibility tests was determined by averaging the differences between paired observations, and by dividing the differences by the average of the paired observations expressed as a percentage. LVEDD, left ventricular end-diastolic diameter; LVESD, left ventricular end-systolic diameter; PWTED, posterior wall thickness at end diastole; FS, fractional shortening; RWT, relative wall thickness; HR, heart rate.