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Novel design of a usable and accurate anthropometric caliper.

BACKGROUND
Anthropometric kits are extensively used in workstation and product design projects, and with the advancement of technology, they have turned into highly complex and effective instruments. However, there are still many challenging problems in usability and reliability of application of these kits in real-world settings.


OBJECTIVE
To identify the usability and accuracy issues with a conventional anthropometric caliper, and to propose measurable design features to enhance the functionality of the caliper.


METHODS
The measurement process using a conventional anthropometric caliper was systematically analyzed through detailed hierarchical task analyses. Also, six qualified anthropometry specialists performed heuristic evaluations to gain valuable insights into major usability issues in relation to the existing body measurement devices. Based on the resulting concepts, a mock-up was developed and evaluated against the desired specifications.


RESULTS
Incorrect positioning angle of the caliper, as well as applying various amounts of force by different investigators to push the caliper branches against body parts, appeared to be the main factors introducing inaccuracy to anthropometric data. Installing a spirit level on caliper, and also a pre-programmed microprocessor for real-time saving of the obtained data, facilitated the measurement process for both investigators and subjects.


CONCLUSION
Accuracy, followed by usability is the primary concern in designing anthropometric instruments. However, expectations would vary from one specialist to another. Therefore, trade-offs should be made when incorporating innovative features in novel designed body measurement kits.