Table 2 Cumulative summation score and slope score of the learning curve in single-port thoracoscopic lobectomy for senior thoracic surgeon

1

 − 0.3

0.8

21

11.7

0.2

41

14.7

 − 0.2

2

0.4

0.8

22

11.4

0.2

42

14.4

 − 0.2

3

1.1

0.7

23

11.1

0.1

43

15.1

 − 0.2

4

2.8

0.7

24

11.8

0.1

44

14.8

 − 0.2

5

4.5

0.7

25

11.5

0.1

45

14.5

 − 0.2

6

5.2

0.6

26

11.2

0.1

46

14.2

 − 0.2

7

5.9

0.6

27

11.9

0.1

47

13.9

 − 0.2

8

5.6

0.6

28

11.6

0.0

48

13.6

 − 0.2

9

6.3

0.5

29

11.3

0.0

49

13.3

 − 0.2

10

7

0.5

30

12

0.0

50

14

 − 0.3

11

8.7

0.5

31

12.7

0.0

51

14.7

 − 0.3

12

9.4

0.4

32

13.4

0.0

52

14.4

 − 0.3

13

9.1

0.4

33

13.1

 − 0.1*

53

14.1

 − 0.3

14

9.8

0.4

34

12.8

 − 0.1

54

13.8

 − 0.3

15

9.5

0.4

35

12.5

 − 0.1

55

13.5

 − 0.3

16

10.2

0.3

36

13.2

 − 0.1

56

13.2

 − 0.3

17

10.9

0.3

37

12.9

 − 0.1

57

12.9

 − 0.3

18

10.6

0.3

38

13.6

 − 0.1

58

12.6

 − 0.3

19

12.3

0.2

39

14.3

 − 0.1

59

12.3

 − 0.3

20

12

0.2

40

14

 − 0.2

60

12

 − 0.3