Table 2.
Comparison of dial and digital scale absolute value of weight imprecision at various test loads
|
Calibration weight
|
n
|
Mean |
SD |
*P
|
|---|---|---|---|---|
| Scale | (kg) | (kg) | ||
|
10 kg |
|
|
|
|
| All scales |
55 |
0.2 |
0.3 |
|
| Dial |
18 |
0.4 |
0.3 |
<0.001 |
| Digital |
37 |
0.1 |
0.2 |
|
|
25 kg |
|
|
|
|
| All scales |
60 |
0.4 |
0.5 |
|
| Dial |
18 |
0.7 |
0.5 |
<0.001 |
| Digital |
42 |
0.2 |
0.3 |
|
|
50 kg |
|
|
|
|
| All scales |
61 |
0.4 |
0.4 |
|
| Dial |
18 |
0.7 |
0.5 |
0.004 |
| Digital |
43 |
0.3 |
0.3 |
|
|
75 kg |
|
|
|
|
| All scales |
61 |
0.6 |
0.6 |
|
| Dial |
18 |
1.0 |
0.7 |
<0.001 |
| Digital |
43 |
0.4 |
0.4 |
|
|
100 kg |
|
|
|
|
| All scales |
60 |
0.7 |
0.7 |
|
| Dial |
18 |
1.2 |
0.9 |
0.001 |
| Digital |
42 |
0.54 |
0.5 |
|
|
110 kg |
|
|
|
|
| All scales |
59 |
0.8 |
0.8 |
|
| Dial |
18 |
1.2 |
1.0 |
0.007 |
| Digital | 41 | 0.6 | 0.6 |
SD = standard deviation, CW = calibration weight.
*Data are from unpaired t-tests comparing the absolute values of imprecision at each test load registered by dial versus digital HBS.