. 2019 Mar 2;28(7):1849–1861. doi: 10.1007/s11136-019-02152-6

Table 4.

Regression analysis of the impact of clinical, functional and demographic characteristics of patients and outcome scores for patients and caregivers

	Patient outcomes
N	983	970	158	944	980
Adjusted R²	0.3727	0.2639	0.1752	0.2148	0.1769
ECOG-PS: 1 (Reference group = 0)	− 0.053* (− 0.097, − 0.009)	− 5.748*** (− 8.537, − 2.959)	8.169 (− 0.083, 16.420)	7.539*** (3.099, 11.980)	− 3.908* (− 7.125, − 0.691)
ECOG-PS: 2 (Reference group = 0)	− 0.194*** (− 0.244, − 0.144)	− 12.381*** (− 15.524, − 9.238)	11.106 (− 1.258, 23.471)	18.784*** (13.795, 23.772)	− 11.028*** (− 14.650, − 7.405)
ECOG-PS: 3/4 (Reference group = 0)	− 0.513*** (− 0.580, − 0.447)	− 24.238*** (− 28.359, − 20.117)	50.769*** (21.976, 79.563)	31.110*** (24.486, 37.734)	− 19.480*** (− 24.247, − 14.712)
Histology: squamous (Reference group: non-squamous)	− 0.003 (− 0.038, 0.033)	1.572 (− 0.652, 3.797)	− 0.345 (− 8.840, 8.149)	− 0.870 (− 4.416, 2.675)	0.628 (− 1.940, 3.196)
Current stage: stage IV (Reference group: stage IIIb)	− 0.081** (− 0.131, − 0.032)	− 1.342 (− 4.489, 1.805)	9.599 (− 1.933, 21.131)	7.070** (2.084, 12.056)	− 5.973** (− 9.576, − 2.369)
Disease duration (weeks)	− 0.001** (− 0.001, − 0.000)	− 0.067*** (− 0.090, − 0.045)	0.024 (− 0.074, 0.123)	0.067*** (0.031, 0.104)	− 0.067*** (− 0.094, − 0.041)
Current chemotherapy treatment: yes (Reference group: no)	0.036 (− 0.004, 0.076)	1.631 (− 0.866, 4.128)	10.977* (0.660, 21.295)	− 4.110* (− 8.105, − 0.115)	− 0.170 (− 3.047, 2.707)
Brain metastases: yes (Reference group: no)	0.001 (− 0.052, 0.054)	− 1.160 (− 4.475, 2.155)	6.278 (− 6.121, 18.677)	4.100 (− 1.213, 9.414)	− 2.285 (− 6.092, 1.521)
Age: 65 years or older (Reference group: <65 years)	− 0.051** (− 0.085, − 0.017)	− 4.342*** (− 6.463, − 2.220)	− 11.468 (− 27.005, 4.068)	4.212* (0.827, 7.597)	− 5.646*** (− 8.091, − 3.201)
Sex: male (Reference group: female)	0.024 (− 0.011, 0.059)	1.892 (− 0.298, 4.082)	− 4.922 (− 13.433, 3.588)	− 1.702 (− 5.218, 1.814)	1.909 (− 0.616, 4.435)
Smoking status: current/ex-smoker (Reference group: never smoked)	− 0.005 (− 0.045, 0.036)	− 5.001*** (− 7.561, − 2.441)	7.081 (− 1.166, 15.328)	7.961*** (3.849, 12.074)	− 3.968** (− 6.917, − 1.020)
Country: Germany (Reference group: France)	0.176*** (0.136, 0.216)	4.442*** (1.956, 6.929)	− 15.309** (− 26.217, − 4.401)	− 5.888** (− 9.889, − 1.888)	− 3.780** (− 6.647, − 0.914)
Country: Italy (Reference group: France)	0.257*** (0.217, 0.298)	1.003 (− 1.518, 3.524)	− 9.619 (− 20.889, 1.651)	− 10.646*** (− 14.694, − 6.597)	1.724 (− 1.173, 4.622)

Patient outcomes

EQ-5D-3L

EQ VAS

WPAI-GH: overall work impairment

WPAI-GH: activity impairment

EORTC-QLQ-C30: global health status

983

970

158

944

980

Adjusted R²

0.3727

0.2639

0.1752

0.2148

0.1769

ECOG-PS: 1

(Reference group = 0)

− 0.053*

(− 0.097, − 0.009)

− 5.748***

(− 8.537, − 2.959)

8.169

(− 0.083, 16.420)

7.539***

(3.099, 11.980)

− 3.908*

(− 7.125, − 0.691)

ECOG-PS: 2

(Reference group = 0)

− 0.194***

(− 0.244, − 0.144)

− 12.381***

(− 15.524, − 9.238)

11.106

(− 1.258, 23.471)

18.784***

(13.795, 23.772)

− 11.028***

(− 14.650, − 7.405)

ECOG-PS: 3/4

(Reference group = 0)

− 0.513***

(− 0.580, − 0.447)

− 24.238***

(− 28.359, − 20.117)

50.769***

(21.976, 79.563)

31.110***

(24.486, 37.734)

− 19.480***

(− 24.247, − 14.712)

Histology: squamous

(Reference group: non-squamous)

− 0.003

(− 0.038, 0.033)

1.572

(− 0.652, 3.797)

− 0.345

(− 8.840, 8.149)

− 0.870

(− 4.416, 2.675)

0.628

(− 1.940, 3.196)

Current stage: stage IV

(Reference group: stage IIIb)

− 0.081**

(− 0.131, − 0.032)

− 1.342

(− 4.489, 1.805)

9.599

(− 1.933, 21.131)

7.070**

(2.084, 12.056)

− 5.973**

(− 9.576, − 2.369)

Disease duration (weeks)

− 0.001**

(− 0.001, − 0.000)

− 0.067***

(− 0.090, − 0.045)

0.024

(− 0.074, 0.123)

0.067***

(0.031, 0.104)

− 0.067***

(− 0.094, − 0.041)

Current chemotherapy treatment: yes

(Reference group: no)

0.036

(− 0.004, 0.076)

1.631

(− 0.866, 4.128)

10.977*

(0.660, 21.295)

− 4.110*

(− 8.105, − 0.115)

− 0.170

(− 3.047, 2.707)

Brain metastases: yes

(Reference group: no)

0.001

(− 0.052, 0.054)

− 1.160

(− 4.475, 2.155)

6.278

(− 6.121, 18.677)

4.100

(− 1.213, 9.414)

− 2.285

(− 6.092, 1.521)

Age: 65 years or older

(Reference group: <65 years)

− 0.051**

(− 0.085, − 0.017)

− 4.342***

(− 6.463, − 2.220)

− 11.468

(− 27.005, 4.068)

4.212*

(0.827, 7.597)

− 5.646***

(− 8.091, − 3.201)

Sex: male

(Reference group: female)

0.024

(− 0.011, 0.059)

1.892

(− 0.298, 4.082)

− 4.922

(− 13.433, 3.588)

− 1.702

(− 5.218, 1.814)

1.909

(− 0.616, 4.435)

Smoking status: current/ex-smoker

(Reference group: never smoked)

− 0.005

(− 0.045, 0.036)

− 5.001***

(− 7.561, − 2.441)

7.081

(− 1.166, 15.328)

7.961***

(3.849, 12.074)

− 3.968**

(− 6.917, − 1.020)

Country: Germany

(Reference group: France)

0.176***

(0.136, 0.216)

4.442***

(1.956, 6.929)

− 15.309**

(− 26.217, − 4.401)

− 5.888**

(− 9.889, − 1.888)

− 3.780**

(− 6.647, − 0.914)

Country: Italy

(Reference group: France)

0.257***

(0.217, 0.298)

1.003

(− 1.518, 3.524)

− 9.619

(− 20.889, 1.651)

− 10.646***

(− 14.694, − 6.597)

1.724

(− 1.173, 4.622)

	Caregiver outcomes
N	391	389	153	393	396
Adjusted R²	0.0695	0.1192	0.0107	0.1964	0.0828
ECOG-PS: 1 (Reference group = 0)	0.022 (− 0.030, 0.075)	− 2.082 (− 6.922, 2.759)	13.566* (0.609, 26.524)	11.156** (4.159, 18.152)	5.071* (0.735, 9.408)
ECOG-PS: 2 (Reference group = 0)	− 0.025 (− 0.083, 0.032)	− 3.776 (− 9.063, 1.512)	1.265 (− 13.145, 15.676)	8.846* (1.155, 16.537)	7.620** (2.869, 12.371)
ECOG-PS: 3/4 (Reference group = 0)	− 0.068 (− 0.144, 0.008)	− 7.178* (− 14.167, − 0.189)	3.669 (− 14.829, 22.166)	26.375*** (16.827, 35.923)	15.662*** (9.780, 21.544)
Histology: squamous (Reference group: non-squamous)	0.005 (− 0.036, 0.045)	− 0.029 (− 3.706, 3.648)	− 8.511 (− 19.060, 2.037)	− 1.649 (− 6.971, 3.673)	− 1.156 (− 4.405, 2.093)
Current stage: stage IV (Reference group: stage IIIb)	− 0.029 (− 0.106, 0.049)	− 2.052 (− 9.084, 4.980)	6.470 (− 13.696, 26.637)	− 0.298 (− 9.558, 8.963)	2.063 (− 3.756, 7.882)
Disease duration (weeks)	0.000 (− 0.000, 0.000)	− 0.002 (− 0.040, 0.036)	0.035 (− 0.049, 0.119)	0.083** (0.026, 0.139)	0.006 (− 0.028, 0.039)
Current chemotherapy treatment: yes (Reference group: no)	0.017 (− 0.029, 0.062)	− 0.744 (− 4.914, 3.427)	0.184 (− 11.101, 11.470)	0.689 (− 5.328, 6.706)	− 1.793 (− 5.471, 1.885)
Brain metastases: yes (Reference group: no)	− 0.014 (− 0.067, 0.038)	− 1.002 (− 5.814, 3.810)	3.970 (− 9.180, 17.121)	2.842 (− 4.102, 9.786)	0.563 (− 3.783, 4.908)
Age: 65 years or older (Reference group: <65 years)	0.026 (− 0.015, 0.066)	3.040 (− 0.653, 6.733)	2.349 (− 7.327, 12.024)	− 3.772 (− 9.117, 1.573)	− 1.609 (− 4.905, 1.688)
Sex: male (Reference group: female)	− 0.043* (− 0.085, − 0.000)	− 1.571 (− 5.401, 2.260)	− 1.128 (− 10.435, 8.178)	− 2.203 (− 7.727, 3.321)	0.363 (− 3.044, 3.771)
Smoking status: Current/ex-smoker (Reference group: never smoked)	− 0.001 (− 0.049, 0.047)	− 2.976 (− 7.368, 1.416)	5.845 (− 5.750, 17.440)	8.446** (2.068, 14.823)	4.985* (1.026, 8.945)
Country: Germany (Reference group: France)	0.047* (0.002, 0.092)	2.243 (− 1.894, 6.380)	− 11.663* (− 22.825, − 0.501)	− 12.747*** (− 18.769, − 6.726)	− 0.740 (− 4.445, 2.965)
Country: Italy (Reference group: France)	0.054* (0.008, 0.101)	− 7.737*** (− 12.026, − 3.448)	4.861 (− 9.050, 18.772)	− 0.429 (− 6.559, 5.701)	0.989 (− 2.768, 4.746)
Caregiver’s age (years)	− 0.002* (− 0.003, − 0.000)	− 0.343*** (− 0.478, − 0.208)	0.033 (− 0.440, 0.506)	0.299** (0.100, 0.497)	− 0.009 (− 0.131, 0.112)
Caregiver’s sex: male (Reference group: female)	0.033 (− 0.009, 0.074)	0.031 (− 3.783, 3.844)	− 2.447 (− 11.933, 7.038)	− 2.849 (− 8.483, 2.786)	− 2.350 (− 5.754, 1.055)

Caregiver outcomes

EQ-5D-3L

EQ VAS

WPAI-GH: overall work impairment

WPAI-GH: activity impairment

Zarit burden index

391

389

153

393

396

Adjusted R²

0.0695

0.1192

0.0107

0.1964

0.0828

ECOG-PS: 1

(Reference group = 0)

0.022

(− 0.030, 0.075)

− 2.082

(− 6.922, 2.759)

13.566*

(0.609, 26.524)

11.156**

(4.159, 18.152)

5.071*

(0.735, 9.408)

ECOG-PS: 2

(Reference group = 0)

− 0.025

(− 0.083, 0.032)

− 3.776

(− 9.063, 1.512)

1.265

(− 13.145, 15.676)

8.846*

(1.155, 16.537)

7.620**

(2.869, 12.371)

ECOG-PS: 3/4

(Reference group = 0)

− 0.068

(− 0.144, 0.008)

− 7.178*

(− 14.167, − 0.189)

3.669

(− 14.829, 22.166)

26.375***

(16.827, 35.923)

15.662***

(9.780, 21.544)

Histology: squamous

(Reference group: non-squamous)

0.005

(− 0.036, 0.045)

− 0.029

(− 3.706, 3.648)

− 8.511

(− 19.060, 2.037)

− 1.649

(− 6.971, 3.673)

− 1.156

(− 4.405, 2.093)

Current stage: stage IV

(Reference group: stage IIIb)

− 0.029

(− 0.106, 0.049)

− 2.052

(− 9.084, 4.980)

6.470

(− 13.696, 26.637)

− 0.298

(− 9.558, 8.963)

2.063

(− 3.756, 7.882)

Disease duration (weeks)

0.000

(− 0.000, 0.000)

− 0.002

(− 0.040, 0.036)

0.035

(− 0.049, 0.119)

0.083**

(0.026, 0.139)

0.006

(− 0.028, 0.039)

Current chemotherapy treatment: yes

(Reference group: no)

0.017

(− 0.029, 0.062)

− 0.744

(− 4.914, 3.427)

0.184

(− 11.101, 11.470)

0.689

(− 5.328, 6.706)

− 1.793

(− 5.471, 1.885)

Brain metastases: yes

(Reference group: no)

− 0.014

(− 0.067, 0.038)

− 1.002

(− 5.814, 3.810)

3.970

(− 9.180, 17.121)

2.842

(− 4.102, 9.786)

0.563

(− 3.783, 4.908)

Age: 65 years or older

(Reference group: <65 years)

0.026

(− 0.015, 0.066)

3.040

(− 0.653, 6.733)

2.349

(− 7.327, 12.024)

− 3.772

(− 9.117, 1.573)

− 1.609

(− 4.905, 1.688)

Sex: male

(Reference group: female)

− 0.043*

(− 0.085, − 0.000)

− 1.571

(− 5.401, 2.260)

− 1.128

(− 10.435, 8.178)

− 2.203

(− 7.727, 3.321)

0.363

(− 3.044, 3.771)

Smoking status: Current/ex-smoker

(Reference group: never smoked)

− 0.001

(− 0.049, 0.047)

− 2.976

(− 7.368, 1.416)

5.845

(− 5.750, 17.440)

8.446**

(2.068, 14.823)

4.985*

(1.026, 8.945)

Country: Germany

(Reference group: France)

0.047*

(0.002, 0.092)

2.243

(− 1.894, 6.380)

− 11.663*

(− 22.825, − 0.501)

− 12.747***

(− 18.769, − 6.726)

− 0.740

(− 4.445, 2.965)

Country: Italy

(Reference group: France)

0.054*

(0.008, 0.101)

− 7.737***

(− 12.026, − 3.448)

4.861

(− 9.050, 18.772)

− 0.429

(− 6.559, 5.701)

0.989

(− 2.768, 4.746)

Caregiver’s age (years)

− 0.002*

(− 0.003, − 0.000)

− 0.343***

(− 0.478, − 0.208)

0.033

(− 0.440, 0.506)

0.299**

(0.100, 0.497)

− 0.009

(− 0.131, 0.112)

Caregiver’s sex: male

(Reference group: female)

0.033

(− 0.009, 0.074)

0.031

(− 3.783, 3.844)

− 2.447

(− 11.933, 7.038)

− 2.849

(− 8.483, 2.786)

− 2.350

(− 5.754, 1.055)

All covariates relate to the patient unless otherwise specified

ECOG-PS Eastern Cooperative Oncology Group Performance Status, EORTC QLQ-C30 European Organization for the Research and Treatment of Cancer Quality of Life Questionnaire-Core 30, EQ-5D-3L EuroQol 5-Dimension 3-Level, VAS visual analogue scale, WPAI-GH work productivity and activity impairment: general health, ZBI Zarit burden interview

* p < 0.05, ** p < 0.01, *** p < 0.001; data presented are coefficient (95% confidence interval)