Successful novice's training in obtaining accurate assessment of carotid IMT using an automated ultrasound system

The aim of this study was to assess the feasibility and learning curve of training novice operators in using automated ultrasound to achieve satisfactory carotid intima-media thickness (CIMT) measurements.

Four novices underwent 4 weeks carotid ultrasound training using a newly developed automated ultrasonograph. A longitudinal B-mode image of the distal right common carotid artery (CCA) was acquired in 96 patients. The interoperator CIMT reproducibility was analysed by the coefficient of variation (CV) and intraclass correlation coefficient (ICC) for every week and compared with that from an expert operator. The weekly mean CV of the measurements on the 24 patients made by all novices was consistently reduced: 0.06, 0.05, 0.03, and 0.02, respectively. For the expert, the mean CV was 0.02, 0.02, 0.03, and 0.02, respectively. The novices' standard deviation (SD) of CVs also reduced weekly from 0.04 in the first week to 0.01 in the last week (P < 0.05). The corresponding weekly variation in the SD for the expert was 0.02 for the first week to 0.01 in the last week (P = 0.27). The agreement between measurements made by the novices was expressed by the ICC being 0.97 (P < 0.001) in the first week and increased to 0.99 (P < 0.001) in the fourth week.

CIMT assessment by novices using an automated ultrasound could be reliably achievable after a short training period. These results may have encouraging implications when designing screening programmes for primary prevention in community health service.