Stability of urinary biomarkers at prolonged storage at −20°C
| Collection and Processing | Mean Percentage Difference (95% confidence interval of mean % difference) | ||
|---|---|---|---|
| KIM-1, n = 32 | NAG, n = 32 | NGAL, n = 32 | |
| Prolonged storage at −20 and −80°C | |||
| 2 yr with 3 repeat freeze and thaw cycles (−20 versus −80°C) | −15.08 (−21.26 to −8.91) | −8.88 (−16.03 to −1.74) | −40.24 (−52.67 to −27.82) |
| compared with initial biomarker levels 2 yr before at −20°C | −6.75 (−16.99 to 3.49) | −6.11 (−14.44 to 2.22) | NA |