Table 2 Results of the logistic multilevel analysis

 Intercept

0.82

.94

0.01–101.70

  Sex

Female

Male

0.32

<.001

0.16–0.64

  Age

Younger than 35 years

1.30

.46

0.64–2.63

35–44 years

1.09

.63

0.77–1.54

45–54 years

1.15

.22

0.92–1.45

55–64 years

65–74 years

1.25

.05

1.00–1.56

75–84 years

1.01

.93

0.81–1.27

Older than 84 years

0.57

.002

0.40–0.81

  Prior cancer diagnosis

Yes

0.71

.10

0.47–1.07

No

  T-staging

TIS/DCIS

0.47

<.001

0.28–0.49

Invasive breast cancer

TX

1.31

.63

0.44–3.93

  N-staging

N0

> N0

1.07

.47

0.90–1.28

NX

0.78

.13

0.56–1.08

  M-staging

M0

M1

0.98

.89

0.70–1.35

  Both breasts affected (metachronous and synchronous)

No

Yes

1.48

.03

1.03–2.11

  Therapy type

Surgery with recommendation for chemotherapy

1.12

.25

0.92–1.36

Surgery without recommendation for chemotherapy

No surgery

0.08

<.001

0.06–0.11

  Date of diagnosis

2015

1.56

<.001

1.31–1.85

2016

2017

2.81

<.001

2.33–3.41

  Municipality

<  20,000 population

1.94

.53

0.25–14.96

20,000–100,000 population

>  100,000 population

1.51

.56

0.38–6.10

  Teaching status

None

0.26

.24

0.03–2.38

Academic

University

0.28

.42

0.01–6.30

  Ownership

Not-for-profit

Private

2.47

.50

0.18–33.22

  Number of primary cases

Continuous

1.02

.12

1.00–1.04

  Years since first certification

Continuous

0.91

.46

0.72–1.16

  N patients

6339

  N centers

13

  ICC (nullmodel)

0.20 (0.24)