Table 1 Mixed effects models predicting the levels of six different measures of instability using age, the number of SBS2 and SBS13 mutations, accounting for the effects of tumour type as a random variable. The number of SBS2 and SBS13 mutations was log transformed using the natural logarithm. These models correspond to models 3-9, detailed in Additional file 1: Supplementary Note 1. SV structural variant, CN copy number, PGA Proportion of the Genome Altered, INDELs Insertions and Deletions, ID8 INDEL signature 8, ID6 INDEL signature 6, LMM linear mixed effects model, NB negative binomial, ZINB zero inflated negative binomial, AIC Akaike Information Criterion)

Count model: (Intercept)

Coefficient

3.62

4.42

0.397

1.36

0.514

5.46

95% CI

(−9.49,16.7)

(4.01,4.83)

(−1.26,2.05)

(0.257,2.46)

(−1.52,2.55)

(1.30,9.63)

p value

0.589

3.62x10^{−99∗∗∗}

0.638

0.0157^∗

0.620

0.0102^∗

Count model: Age

Coefficient

0.0634

−0.000362

0.0323

0.0393

0.0250

−0.0562

95% CI

(−0.0731,0.200)

(−0.00370,0.00298)

(0.00624,0.0583)

(0.0219,0.0567)

(−0.00703,0.0570)

(−0.121,0.0083)

p value

0.363

0.832

0.0151^∗

9.61x10^{−6∗∗∗}

0.126

0.0877

Count model:

Coefficient

6.50

0.247

0.684

0.725

0.589

0.0191

log (SBS2/13)

95% CI

(4.99,8.01)

(0.206,0.289)

(0.442,0.927)

(0.562,0.888)

(0.281,0.897)

(−0.578,0.616)

p value

2.51×10^{−16∗∗∗}

5.66×10^{−32∗∗∗}

3.14×10^{−8∗∗∗}

3.43×10^{−18∗∗∗}

1.77×10^{−4∗∗∗}

0.950

Count model:

Coefficient

−0.00515

−0.00552

−0.00372

0.00738

Age:log (SBS2/13)

95% CI

(-0.00904,-0.00126)

(−0.00812,−0.00292)

(−0.00854,0.00110)

(−0.0019,0.0166)

p value

0.00942^∗∗

3.14×10^{−5∗∗∗}

0.130

0.118

Zero model: (Intercept)

Coefficient

−0.684

1.07

95% CI

(−0.839,−0.530)

(0.903,1.24)

p value

4.20×10^{−18∗∗∗}

3.85×10^{−36∗∗∗}

AIC

6738.4

10,064.1

8701.2

10,444.3

6357.3

3270.9

Log likelihood

−3364.2

−5027.1

−4344.6

−5216.1

−3171.6

−1628.5

Num. obs.

725

725

717

725

725

725

Num. tumour type:

26

26

26

26

26

26