Table 2 Coding scheme with three levels.

Documented and practical training objectives

8

8

The training model

Training model

Learning environment

Development opportunity

Doctoral motivation

Cognitive tendency

Relationship network

Professional identity

Emotional experience

The admission process

7

7

The level of teachers

2

2

The curriculum system of Ed.D

11

12

Teaching and learning in real situations

5

5

Thesis requirements for Ed.D

7

8

Physical learning environment at home and in school

5

6

Different learning environment

Independent and group learning environment

3

4

Competitions are easier to win

2

2

The development opportunity brought by the status of Ed.D in education

Rich learning and teaching resources

3

4

More opportunities to attend conferences as a Ed.D candidate

2

2

The status of the unit is imperceptibly improved

10

10

You have the choice to move up after graduation

8

9

Awards and promotions

3

4

The motivation of doctoral study is utilitarian

14

15

Motivation to get a Ed.D

Come with an ideal and a sense of mission

12

14

Ed.D on the presupposition of graduation outcomes

7

8

Expectations for academic outcomes

The position of Ed.D on their own roles

4

4

Assumptions about the input of Ed.D

5

5

Classmates encourage and learn from each other

3

3

The relationship supervisors, teachers, peers, and classmates

Regular and irregular groups communicate

9

10

Conduct academic discussions with tutors and teachers

11

11

Share reports at academic conferences at home and abroad

2

2

To Ed.D on their professional cognition

4

4

To understand their profession

The degree of match between personal preference and major

2

2

Comply with and violate professional regulations

2

3

The process of studying was smooth and enjoyable

4

4

Aware of their emotional states

Always in a state of anxiety and insecurity

6

7