Table 2.

Analytes most affected (cells highlighted with bold) by storage temperature defined as |${\mathrm{S}}_{\mathrm{d}}$| > 1.5 or by storage time in different temperatures defined as storage time associated with ${\log }_2\left({\mathrm{fc}}_{\mathrm{bm}}\right)$ at a Bonferroni corrected significance threshold of p < 2.6 × 10^–4.

Analyte	Storage temperature			Storage time
	${\mathrm{\mu }}_{\mathrm{d}}$	${\mathrm{S}}_{\mathrm{d}}$	${\mathrm{P}}_{\mathrm{paired}}$	${\mathrm{fc}}_{\mathrm{time}}$	${\mathrm{P}}_{\mathrm{time}}$
Kallistatin (643.4/971.6)	281.8	4.32	2.6 × 10–11 t	0.90	2.4 × 10–01
Neutrophil gelatinase-associated lipocalin	169.9	2.91	6.6 × 10–09 t	1.06	8.2 × 10–02
Methionine	22.3	2.69	1.9 × 10–08 t	1.29	4.8 × 10–03
Free cystine	55.9	2.51	3.1 × 10–05 w	1.25	1.0 × 10–04
Glutamine	336.8	2.36	1.1 × 10–07 t	1.31	1.8 × 10–04
Glutamate	− 201.1	− 2.09	5.0 × 10–07 t	0.88	2.7 × 10–04
Free carnitine	− 5.3	− 2.05	3.1 × 10–05 w	0.99	2.0 × 10–02
C4 carnitine	76.2	1.98	1.0 × 10–06 t	1.08	5.7 × 10–06
Interleukin-1 receptor type 2	− 2.1	− 1.79	3.2 × 10–06 t	0.99	4.4 × 10–01
Interleukin-1 receptor type 1	− 379.6	− 1.71	5.6 × 10–06 t	0.93	5.9 × 10–02
C2 Carnitine	4.1	1.65	8.4 × 10–06 t	1.41	4.1 × 10–08
Sulphocysteine	1034.7	1.60	3.1 × 10–05 w	1.28	4.3 × 10–05
C6 carnitine	12.6	1.02	4.8 × 10–04 w	1.10	1.7 × 10–04
C3 CARNITINE	151.2	1.01	4.8 × 10–04 w	1.14	7.7 × 10–06
Glutamate/glutamine	− 3.4	− 0.63	3.1 × 10–05 w	0.67	1.0 × 10–04

$f{c}_{\mathit{bm}}$ is the ratio of analyte levels for the paired samples at − 80 °C and − 20 °C, ${\mu }_d$ is the mean of the difference between paired − 80 °C and − 20 °C samples, $S_d$ is the score for difference between paired − 80 °C and − 20 °C samples, $S_d={\mu }_d/{\sigma }_d$, where ${\sigma }_d$ is the standard deviation of the difference between paired − 80 °C and − 20 °C samples, $P_{\mathit{paired}}$ is the paired t-test or Wilcoxon signed rank test p-value for the difference between − 80 and − 20 °C samples, $f{c}_{\mathit{time}}$ is the linear model estimate for the fold change per 1 year of storage, $P_{\mathit{time}}$ is the linear model p-value for the $f{c}_{\mathit{time}}$ estimate, ^t paired t-test, ^w paired Wilcoxon signed rank test.