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Quality control in ultrasound studies on atherosclerosis

This review discusses the quality control of equipment and technician performance in long term, multicentre trials using ultrasound detection and quantification of atherosclerosis. Examples on how such quality control measures could be implemented are given. Based on our own experience and that of other groups we suggest the following items as being important when planning for quality control in this type of study. 1. Write down the specifications demanded with regard to the ultrasound equipment and reading stations. 2. Compare the commercially available equipment on those characteristics by means of in-vitro and/or in-vivo testing. 3. Select the most suitable equipment for all centres and check it before shipping. 4. Sign a full maintenance agreement for all centres. 5. Evaluate the ultrasound devices and reading stations regularly during the study using phantoms. 6. Train sonographer and readers thoroughly before the start of the study. Certify those who successfully complete the training programme and demonstrate proficiency in scanning or reading. 7. Determine each sonographer's/reader's variability before and repeatedly during the study. Give feedback on performance to the sonographer/reader. 8. Create a regular retraining programme for all sonographers/readers and extend for those with poor performance. 9. Feed all the above information to a Data Quality Control Committee, having the ultimate responsibility for the quality control in the study.