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ATOSS Tasks & Scoring

 

During formal assessment, each task will be timed and assigned a numeric score based on a set of specific micro-skills that is relevant for that task. These will serve as the basis for an overall performance score for the task.

  • Time: Learners will be timed (in seconds) on their performance of each task from start to finish of the task. There will be a cutoff time associated with each task; the cutoff times were determined as 4 standard deviations away from the mean of benchmark scores.

  • Score: Numeric scores will be determined based on the sum of individual scores for each micro-skill for a given task. Maximum possible score is 30 or 35, depending on the number of micro-skills associated with a task. Each micro-skill will receive a score from 1-5:

Score:

1

2

3

4

5

Description:

Unable to complete task

Completed task w/ major errors

Completed task w/ minor errors

Proficient, no errors, some awkward moves

Expert, no errors, smooth and efficient
  • Overall performance score: Times (in seconds) and scores for each task may be converted to a single overall performance score (0-50) using a formula that incorporates expert performance and a relative time/score weighting. Expert participants were defined as those who had performed 50+ cases per year where advanced open skills were employed.
    • A template score calculator is provided (can access via Google doc or by downloading excel file); time/score weightings can be adjusted based on institution’s preference.
    • A score of 50 (or higher) represents performance at the expert level; for every 10 points below 50, the score is 1 standard deviation away from expert performance.
    • Scoring formulas are derived from the following expert data (n=14):

Task

Score (Points)

Time (Seconds)

Example Scoring Formula

Using 25% Time/75% Score Weightings

Mean

SD

Mean

SD

1

28.57

1.45

36.86

13.64

([(Total score - 28.57) / 1.45 ]*0.75 - [(Time - 36.86) / 13.64]*0.25) *10 + 50

2

33.86

1.17

41.14

11.61

([(Total score - 33.86) / 1.17 ]*0.75 - [(Time - 41.14) / 11.61]*0.25) *10 + 50

3

33.71

2.52

75.71

17.87

([(Total score - 33.71) / 2.52 ]*0.75 - [(Time - 75.71) / 17.87]*0.25) *10 + 50

4

27.57

2.56

113.07

23.33

([(Total score - 27.57) / 2.56 ]*0.75 - [(Time - 113.07) / 23.33]*0.25) *10 + 50

5

32.07

3.20

87.50

23.30

([(Total score - 32.07) / 3.20 ]*0.75 - [(Time - 87.50) / 23.30]*0.25) *10 + 50

6

28.50

2.41

126.79

34.24

([(Total score - 28.50) / 2.41 ]*0.75 - [(Time - 126.79) / 34.24]*0.25) *10 + 50
  • Tasks:
    • Task 1: Suture tying without needle, at depth
    • Task 2: Suture tying with needle, at depth
    • Task 3: Continuous suturing, pitch and catch, superficial
    • Task 4: Continuous suturing, push-push-pull, superficial
    • Task 5: Continuous suturing, pitch and catch, at depth
    • Task 6: Continuous suturing, push-push-pull, at depth
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