Table 3 Regressions between the measured variables. Regressions between the measured variables using the general model (second column) and the dummy variable method (third column). ns = not significant. Cond. = Conductivity, Vol. = Volume. r = Pearson's correlation coefficient; p = significance of r; A: intercept with Y-axis (±SD is also expressed); B: Slope of the regression line (±SD is also expressed); p (B): significance of B. The correlations refer to the concentrations of H₂O₂ and MDA. E_i = dummy variable. Its value is 1 for the i-th subject, -1 for the last subject, 0 elsewhere.

H₂O₂ vs Vol.

Log (H₂O₂) = A + B*Volume

r

P

A

B

p (B)

A

B

p (B)

-0.29

<0.01

-0.73 ± 0.08

(-2.7 ± 0.9)*10^-5

<0.01

-0.88 ± 0.08

(-8.5 ± 5.2)*10^-5

ns

MDA vs Vol.

Log (MDA) = A + B*Volume

Log (MDA) = A + B*Volume + Σ _i C _i E _i

r

P

A

B

p (B)

A

B

p (B)

-0.54

<0.01

1.01 ± 0.04

(-2.4 ± 0.4)*10^-4

<0.01

1.00 ± 0.04

(-2.3 ± 0.4)*10^-4

<0.01

Cond. vs Vol.

Log (Cond.) = A + B*Volume

Log (Cond.) = A + B*Volume + Σ _i C _i E _i

r

P

A

B

p (B)

A

B

p (B)

-0.34

<0.01

0.94 ± 0.13

(-5.2 ± 1.5)*10^-4

<0.01

1.05 ± 0.13

(-6.5 ± 1.4)*10^-4

<0.01

MDA vs H ₂ O ₂

Log (MDA) = A + B*Log (H ₂ O ₂ )

Log (MDA) = A + B*Log (H ₂ O ₂ ) + Σ _i C _i E _i

r

P

A

B

p (B)

A

B

p (B)

0.53

<0.01

1.05 ± 0.04

0.25 ± 0.04

<0.01

1.16 ± 0.09

0.37 ± 0.10

<0.01

H ₂ O ₂ vs Cond.

Log (H ₂ O ₂ ) = A + B*Log (Cond.)

Log (H ₂ O ₂ ) = A + B*Log (Cond.) + Σ _i C _i E _i

r

P

A

B

p (B)

A

B

p (B)

0.12

Ns

Ns

ns

MDA vs. Cond.

Log (MDA) = A + B*Log (Cond.)

Log (MDA) = A + B*Log (Cond.) + Σ _i C _i E _i

r

P

A

B

p (B)

A

B

p (B)

0.21

<0.05

0.78 ± 0.02

0.06 ± 0.03

<0.05

0.76 ± 0.02

0.10 ± 0.03

<0.01