Table 4 Univariate and multivariate associations between explanatory variables and the odds of SDB failure. Odds ratios (ORs) below 1 indicate lower odds than the reference category, and vice versa

Distal level factors

 Age of the decedent

  18 to 59 years

[1.00]

-

[1.00]

-

  0 years

0.93

0.83 to 1.03

0.172

0.91

0.79 to 1.05

0.203

  1 to 4 years

0.83

0.71 to 0.97

0.016

0.73

0.60 to 0.89

0.002

  5 to 17 years

1.02

0.88 to 1.19

0.786

0.91

0.75 to 1.11

0.345

  ≥ 60 years

1.18

1.06 to 1.31

0.002

1.04

0.92 to 1.19

0.531

 Gender of the decedent

  Male

[1.00]

-

[1.00]

-

  Female

0.92

0.85 to 1.00

0.047

0.93

0.84 to 1.03

0.158

 Number of health facilities per 100,000 population within the health zone

  ≥ 50.0

[1.00]

-

[1.00]

-

  25.0 to 49.9

1.26

1.09 to 1.44

0.001

1.21

0.98 to 1.49

0.070

  < 25.0

2.33

2.11 to 2.58

< 0.001

1.57

1.07 to 2.30

0.021

 Road length per 100,000 population within the health zone

  ≥ 400 km

[1.00]

-

  200 to 399 km

0.89

0.66 to 1.19

0.427

  < 200 km

0.36

0.27 to 0.48

< 0.001

 Mining activity within the health zone

  No mining

[1.00]

-

  Some mining

0.43

0.38 to 0.49

< 0.001

Intermediate level factors

 Stage in the epidemic within the health zone

  No confirmed cases yet

[1.00]

-

[1.00]

-

  During epidemic

0.95

0.71 to 1.27

0.737

2.14

1.35 to 3.38

0.001

  Post-epidemic

1.29

0.98 to 1.69

0.069

3.60

2.32 to 5.58

< 0.001

 Any confirmed EVD cases during the previous 6 weeks within the health zone

  No

[1.00]

-

[1.00]

-

  Yes

0.59

0.52 to 0.67

< 0.001

0.49

0.40 to 0.60

< 0.001

 Attacks against the EVD response during the previous 6 weeks within the health zone

  No

[1.00]

-

  Yes

1.01

0.92 to 1.11

0.798

 Any suspension of EVD response activities during the previous 6 weeks within the health zone

  No

[1.00]

-

[1.00]

-

  Yes

0.78

0.72 to 0.85

< 0.001

1.61

1.43 to 1.82

< 0.001

 Number of deaths due to insecurity events per 100,000 population occurring during the previous 2 weeks within the district (territoire)

  0

[1.00]

-

[1.00]

-

  > 0

1.53

1.38 to 1.71

< 0.001

1.73

1.47 to 2.03

< 0.001

 Presence of an operational EVD treatment centre or transit/isolation centre within the health zone

  Yes

[1.00]

-

[1.00]

-

  No

2.30

2.09 to 2.52

< 0.001

3.59

2.92 to 4.42

< 0.001

 Number of mobile phone networks with reception within the health zone

  < 4

[1.00]

-

[1.00]

-

  4

0.43

0.39 to 0.47

< 0.001

1.53

1.10 to 2.12

0.011

 Number of radio frequencies with reception within the health zone

  < 10

[1.00]

-

[1.00]

-

  10 to 19

0.44

0.38 to 0.52

< 0.001

3.61

2.51 to 5.21

< 0.001

  ≥ 20

0.87

0.76 to 0.99

0.032

7.43

5.77 to 9.58

< 0.001

Proximal level factors

 SDB team type

  Red Cross mobile

[1.00]

-

[1.00]

-

  static CEHRB, Red Cross supported

0.68

0.55 to 0.85

< 0.001

0.25

0.18 to 0.35

< 0.001

  Civil Protection (mobile or static CEHRB)

1.22

1.11 to 1.33

< 0.001

0.61

0.54 to 0.70

< 0.001

 Community and/or family nonacceptance of the SDB

  No

[1.00]

-

[1.00]

-

  Yes

37.64

31.19 to 45.42

< 0.001

40.20

32.06 to 50.39

< 0.001

 Setting in which the death occurred

  EVD treatment centre or transit/isolation centre

[1.00]

-

[1.00]

-

  Hospital

7.68

5.83 to 10.12

< 0.001

7.84

5.73 to 10.73

< 0.001

  Community

12.16

9.22 to 16.03

< 0.001

11.18

8.15 to 15.34

< 0.001