1：Experimental Design and Method Selection:

A cross-sectional study design was used to evaluate and compare the Australian and Saudi Arabian radiographers’ knowledge and attitude of paediatric DR. The study was approved by Institutional Review Board (IRB) of the Imam Abdulrahman Bin Faisal University (IRB-2015-04-068). The requirement for ethics approval was waived in Australia by the University of Canberra Human Ethics Committee due to IRB approval of an international survey and as such covering Australia.

2：8). The requirement for ethics approval was waived in Australia by the University of Canberra Human Ethics Committee due to IRB approval of an international survey and as such covering Australia. Sample Selection and Data Sources:

2. Sample Selection and Data Sources: Participants were radiographers from Australia and Saudi Arabia. In Australia, survey information and recruitment of participants was sent via the Australian Society of Medical Imaging and Radiation Therapy (ASMIRT) email system to all members. In Saudi Arabia, participants were contacted through the heads of radiological departments in hospitals.

3：List of Experimental Equipment and Materials:

Not explicitly mentioned.

4：Experimental Procedures and Operational Workflow:

The survey was opened to participants in the first half of 2016 for online completion in Australia, and data were collected electronically. In Saudi Arabia, hard copy surveys were distributed to radiographers in four hospitals.

5：Data Analysis Methods:

Saudi Arabian and Australian radiographers’ knowledge and attitudes about paediatric DR were analysed and compared by using t-test, chi-squared test in SPSS (version 18 – SPSS Inc., Chicago, USA). P-value was calculated using t-test: two samples assuming unequal variances in Microsoft Office Excel to judge if there were significant differences between radiographers’ responses.