Usability testing of stapler

Test background

To evaluate the human-computer interaction interface design of the equipment and instructions, a certain manufacturer conducted a study on one of their electric devicesstaplerusability testingThe test focuses on the safety and operational efficiency of this product, evaluating its overall usability based on the ability of trained participants to use the product and their clinical knowledge and skills to meet the requirements of medical device IEC 62366.

Sound: Quiet, maintaining decibels similar to the actual surgical scene

Lighting: Use surgical shadowless lamps to simulate the lighting intensity of surgical scenes

Simulated surgical workbench: laparoscopic simulator, simulated tissue (foam), puncture device, surgical clamp, ventilator and other surgical scene equipment

Test Overview

•Testing equipment: A certain brand of surgical electric equipmentstapler, matching nail box, user manual

Test location: A simulated operating room in Shanghai

• Lead testers: one moderator, one observation recorder, and one trainer

• Subject users: 20 frontline clinical doctors

Test Process
1. Training

2. Complete manual testing and manual satisfaction questionnaire

3. Complete routine usage scenario tasks

4. Post test interview

5. Complete tasks related to hazardous usage scenarios
6. Post test interview

Test task design
Usage scenarios and corresponding testing tasks:


Human factors research equipment used for testing
•Behavior Observation Analysis System (The Observer XT)

•Audio and Video Recording System (Media Recorder)

•Facial expression analysis system (FaceReader)

•Wearable eye tracker (Tobii Glasses)

•Portable Lab

Behavior Observation Analysis System (The Observer XT)It is a professional behavior event recording software and data integration platform. Encoding, decomposing event sequences, and integrating different data patterns of behavior on a timeline through computer software systems and video cameras.

cooperate, coordinate, collaborateAudio and Video Recording System (Media Recorder)andWearable eye trackerReal time recording of doctors' operational processes from multiple perspectives, and annotation of key tasks and usage issues. outputNumber of usage issuesandOperation task time.


Facial expression analysis system（FaceReader）

Analyze through the FaceReader facial expression analysis system during doctor training and instruction manual testing

negative emotionsThe困惑度Wait for the psychological state, explore the unreasonable design/unclear description that doctors feel during training, instruction reading, and use.


Portable Lab

The portable usability test box can store a complete set of hardware observation devices such as voice, video, eye tracking, etc., and can quickly set up temporary behavior observation rooms in hospitals or simulated scenarios.

Usability issues and improvement suggestions (partial)

In scenario A, the operation time for each doctor to exit the puncture device step is:

In the step of closing the jaws to remove the instrument, 7 doctors (7/20) had difficulty in exiting the puncture device. Among them, the operation time of 5 doctors was * the average time of the participants, and 1 doctor was close to the average time. The difficulty in exiting the puncture device would significantly affect the efficiency of completing the overall anastomosis task.

Design issue: Inconsistent angle between the bending handle and the jaw in the closed state

Due to the safety design of avoiding tearing of organs after the jaws are closed, the jaw bending function fails when the jaws are closed. But the curved handle can still rotate, and the inconsistent angle between the two causes the doctor to misjudge that the jaw angle has returned to the correct position through the already returned curved handle, which makes it difficult to exit the puncture device and cannot receive prompt and effective feedback in a timely manner.

It is worth noting that the 7 doctors (7/20) who had difficulty exiting the puncture device during the first anastomosis operation did not experience (0/20) exit difficulties during the second anastomosis operation after realizing the problem, and the negative emotional intensity of the users also decreased significantly compared to the first time they exited the puncture device. Therefore, if emphasized during product training, the probability and risk of related operational problems can be significantly reduced.

Design suggestion:

1. Improve the inherent safety design, the handle should not be able to bend in the closed state, and should be consistent with the angle of the jaws.

2. Emphasize in product training and instructions the need to open the jaws before adjusting the jaw angle.

If you are interested in the usability testing case of the stapler, please follow the QR code below for more product information and updates!