A side-by-side comparison was conducted using the AMP One Step Amphetamine Test Device and a leading commercially available AMP rapid test. Testing was performed on 300 clinical specimens. Ten percent of the specimens employed were either at -25% or +25% level of the cutoff concentration of 1,000 ng/ml Amphetamine. Presumptive positive results were confirmed by GC/MS. The following results were tabulated:
| Method | Other AMP Rapid Test | Total Results | ||
|---|---|---|---|---|
| AMP One Step Test Device | Results | Positive | Negative | |
| Positive | 141 | 0 | 141 | |
| Negative | 5 | 154 | 159 | |
| Total Results | 146 | 154 | 300 | |
| % Agreement With Commercial Kit | 97% | >99% | 98% | |
When compared to the GC/MS lab testing method at the cutoff concentration of 1,000 ng/ml, the following results were tabulated:
| Method | GC/MS | Total Results | ||
|---|---|---|---|---|
| AMP One Step Test Device | Results | Positive | Negative | |
| Positive | 132 | 9 | 141 | |
| Negative | 4 | 155 | 159 | |
| Total Results | 136 | 164 | 300 | |
| % Agreement With GC/MS Analysis | 97% | 95% | 96% | |
Eighty (80) of these samples were also run using the AMP One Step Amphetamine Test Device by an untrained operator at a different site. Based on GC/MS data, the operator obtained a statistically similar Positive Agreement, Negative Agreement and Overall Agreement rate as the laboratory personnel.
A drug-free urine pool was spiked with Amphetamine at the following concentrations: 0 ng/ml, 500 ng/ml, 750 ng/ml, 1,000 ng/ml, 1,250 ng/ml and 1,500 ng/ml. The result demonstrates >99% accuracy at 50% above and 50% below the cutoff concentration. The data are summarized below:
| Amphetamine Concentration (ng/ml) | Percent of Cutoff | n | Visual Result | |
|---|---|---|---|---|
| Negative | Positive | |||
| 0 | 0% | 30 | 30 | 0 |
| 500 | -50% | 30 | 30 | 0 |
| 750 | -25% | 30 | 22 | 8 |
| 1,000 | Cutoff | 30 | 12 | 18 |
| 1,250 | +25% | 30 | 2 | 28 |
| 1,500 | +50% | 30 | 0 | 30 |
A study was conducted at 3 physician's offices by untrained operators using 3 different lots of product to demonstrate the within run, between run and between operator precision. An identical panel of coded specimens containing no Amphetamine, 25% Amphetamine above and below the cutoff and 50% Amphetamine above and below the 1,000 ng/ml cutoff was provided to each site. The results are given below:
| Amphetamine Concentration (ng/ml) | n | Site A | Site B | Site C | |||
|---|---|---|---|---|---|---|---|
| - | + | - | + | - | + | ||
| 0 | 15 | 15 | 0 | 15 | 0 | 15 | 0 |
| 500 | 15 | 15 | 0 | 15 | 0 | 14 | 1 |
| 750 | 15 | 13 | 2 | 11 | 4 | 11 | 4 |
| 1,250 | 15 | 6 | 9 | 4 | 11 | 4 | 11 |
| 1,500 | 15 | 2 | 13 | 1 | 14 | 1 | 14 |
Fifteen (15) urine samples of normal, high, and low specific gravity ranges were spiked with 500 ng/ml and 1,500 ng/ml of Amphetamine respectively. The AMP One Step Amphetamine Test Device was tested in duplicate using the fifteen neat and spiked urine samples. The results demonstrate that varying ranges of urinary specific gravity does not affect the test results.
The pH of an aliquoted negative urine pool was adjusted to a pH range of 5 to 9 in 1 pH unit increments and spiked with Amphetamine to 500 ng/ml and 1,500 ng/ml. The spiked, pH-adjusted urine was tested with the AMP One Step Amphetamine Test Device in duplicate. The results demonstrate that varying ranges of pH does not interfere with the performance of the test.