The impact of retraining on medium-term (4-month) skill retention among PGY− 1 and − 2 residents in a cardiac point-of-care ultrasound curriculum: a pilot study

Background Medium- and long-term skill decline following a single cardiac point-of-care ultrasound (POCUS) training session remains an educational challenge. Spaced practice may address this issue. This pilot study investigated whether retraining 2 months after initial training mitigated medium-term skill decline. Methods This was a prospective, pre-post educational intervention study conducted between June 2021 and September 2022. We recruited postgraduate year (PGY)−​ 1 and − 2 residents at a tertiary teaching hospital in Japan. The curriculum included an initial 2-h hands-on training to obtain five cardiac POCUS views, followed by 10-min supervised retraining 2 months later. Participants completed 5‑view image acquisition skill assessments at baseline, immediately post-training, 2-month post-training, and 4-month post-training, using a healthy volunteer. The 2-month assessment was performed immediately before the retraining. Three blinded assessors rated the image quality using a previously developed 10-point scoring system. Participants used a hand-held ultrasound (Butterfly iQ). In post-hoc subgroup analyses, we classified participants into three subgroups by baseline skill score regardless of PGY level: low (< 5), intermediate (5 to < 8), and high (≥ 8) to examine variation in skill retention. Results All 26 eligible residents participated in the study. Mean skill scores of the entire cohort were 6.03 (intermediate level) at baseline, 8.69 (high level) at immediate post-training, 7.78 (intermediate level) at 2-month post-training, and 8.05 (high level) at 4-month post-training. The mean score differences were + 2.67 points (95% CI, 1.87 to 3.47) from baseline to immediate post-training, − 0.93 points (95% CI, − 1.63 to − 0.24) from immediate post-training to 2-month post-training, and + 0.20 points (95% CI, − 0.59 to 0.99) from 2- to 4-month post-training. These differences were estimated using a mixed-effects model. In the post-hoc subgroup analyses, the intermediate baseline skill subgroup ( n = 11) achieved a high skill level at 4 months, whereas the low baseline skill subgroup ( n = 9) did not. The high baseline skill subgroup ( n = 6) maintained a high skill level across all three post-training assessments. Conclusions Spaced practice with retraining may mitigate medium-term decline in cardiac POCUS image acquisition skills in a simulated setting. Participants with an intermediate baseline skill level may benefit most from this single retraining curriculum. Clinical Trial Registration International Clinical Trials Registry Platform; JPRN-jRCT1032220488; registered on December 4, 2022.