Table 1 Missing data by country, and how it was handled in imputation models

Total N

323

180

323

274

289

323

237

323

323

Gender

0

0

0

0

0

0

0

0

0

1 binary item

Single item

Age

0

0

0

0

0

0

0

0

0

1 continuous item

Single item

Education

3

0

1

0

2

1

0

0

0

1 categorical item

Single item

Marital status

2

0

0

1

1

1

0

1

0

1 binary item

Single item

Employment

2

0

0

1

1

1

0

2

0

1 binary item

Single item

Number of

 Medical conditions

1

3

0

1

1

0

0

3

0

1 continuous item

Single item

 Medicines

1

1

0

2

1

1

2

6

1

1 continuous item

Single item

 Tablets

3

3

1

3

1

1

3

12

1

1 continuous item

Single item

 Items prescribed

9

6

3

3

1

8

7

26

6

1 continuous item

Single item

Dosage frequency

1

2

0

0

1

0

1

0

0

1 ordered categorical item

Single item

Morisky adherence

0

0

0

0

0

0

0

0

0

4 binary items

Binary item

Medication adherence rating scale

2

3

1

2

1

2

1

4

0

5 ordinal items

Scale

Prescription payment

1

2

0

1

1

1

*

1

*

1 categorical item

Single item

Affordability problem

1

3

2

1

1

3

1

0

*

1 binary item

Single item

Cost coping strategies

2

7

8

3

2

1

*

8

*

6 ordered categorical items

6 single items

Income

 Source

11

23

22

28

12

8

37

46

15

1 categorical item

Single item

 Perception

8

25

20

28

12

7

37

46

14

2 items: ordered categorical item conditional on binary item

2 items

 Ease of borrowing

9

23

20

28

12

7

38

48

14

2 items: ordered categorical item conditional on binary item

2 items

 Total

9

24

21

28

12

6

38

46

14

2 items: ordered categorical item conditional on binary item

2 items

Health status

1

1

0

0

0

0

1

0

0

1 ordered categorical item

Single item

Practitioner

 Type

7

16

17

23

6

7

29

32

10

1 categorical item

Single item

 Gender

10

17

18

22

14

6

29

38

12

1 binary item

Single item

Satisfaction with

 Practitioner

11

18

18

28

2

3

30

35

7

17 ordered categorical items

Scale

 Practice

11

23

18

23

6

3

30

34

11

6 ordered categorical items

Scale

Optimism

6

15

16

20

5

2

26

26

10

6 ordered categorical items

Scale

Illness perception questionnaire: analysed as 8 individual items

9

19

19

25

7

4

31

37

11

8 ordered categorical items

Scale

Necessities

6

15

16

20

5

2

27

27

10

5 ordered categorical items

Scale

Medicine concerns

6

15

16

20

5

2

27

27

10

6 ordered categorical items

Scale

Attitude

9

17

16

24

7

4

30

35

10

7 ordered categorical items

Scale

Barriers (theory of planned behaviour)

10

17

16

23

7

3

30

33

11

1 ordered categorical item

Single item

Facilitators

11

18

16

24

8

5

30

34

11

3 ordered categorical items

Scale

Intention

10

18

17

24

8

4

30

33

10

2 ordered categorical items

Scale

Self efficacy

7

1

16

23

6

3

30

31

10

2 ordered categorical items

Scale

Normative beliefs

10

20

17

24

7

4

30

33

11

3 ordered categorical items

Scale

Barriers

21

22

22

38

18

6

35

35

9

15 ordered categorical items

Scale

Social support

10

19

19

23

20

4

31

43

11

7 ordered categorical items

Scale

Time preference

14

25

23

23

7

21

32

34

19

4 ordered categorical items

4 single items

Discrete choice experiment: not included in analysis

2

5

7

6

2

1

7

12

2

9 binary items

9 single items