Key measurement principles to strengthen the reliability of loading device technologies: Implications to health care practice
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Physiotherapy Program, School of Rehabilitation, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
Faculty of Health Sciences, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
Department of ECE, Bharathiyar College of Engineering and Technology, Pondicherry University, Tamilnadu, India
Leonard H. Joseph   

Physiotherapy Program, School of Rehabilitation Sciences, Faculty of Health Sciences, Universiti Kebangsaan Malaysia, 5th Floor, Bangunan Yayasan Selangor, Jalan Raja Muda Abdul Aziz, 50300 Kuala Lumpur, Malaysia. Tel.: +60 196 781 935.
Submission date: 2015-06-24
Acceptance date: 2016-01-23
Online publication date: 2016-03-09
Publication date: 2020-03-24
Pol. Ann. Med. 2016;23(2):123–128
In practice, reliability of the load measurement device is carried out as a standard practice prior to data collection to eliminate errors in measurement. However, reliability alone cannot confirm the goodness of a measurement device. The other key measurement variables such as accuracy, hysteresis, eccentricity error, uncertainty could affect the device output. This study highlights the importance of several key measurement principles to strengthen the reliability of loading device technologies in health care practice.

To describes a method of testing the key measurement principles necessary to test the goodness of a load measurement technology at clinical or research setting.

Material and methods:
A customized load measurement device was used to elucidate the calibration procedure. To determine the accuracy and hysteresis, a series of ten equally spaced standard loads ranging 10–100 kg was applied from no load to maximum load over device platform. The applied loads were removed in the same order as initially placed. In addition, the repeatability was tested with a load of 20 kg for five trials. Furthermore, the eccentricity error was determined by applying loads over five different quadrants.

Results and discussion:
The result of the method demonstrated that the device has excellent accuracy and repeatability, with no errors in hysteresis, uncertainty, eccentricity.

In addition to reliability, the other proposed key measurement variables are proven essential to test the goodness of a loading device in research and clinical practice.

No authors had any financial or personal relationships with other people or organizations that could have influenced this study.
This study was supported by FRGS/1/2013/SKK10/UKM/03/1. The grant funding had no role in the study design, data collection, analysis, or with writing of this manuscript.
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