Assessment of retention of training in improving the accuracy of needle penetration depth

[Purpose] This study aimed to assess whether the effects of training in fine motor skills, such as improving the accuracy of acupuncture depth, persisted after the training was completed. [Participants and Methods] Fifteen students (age, 28.0 ± 8.4 years) participated in the study. A 0.2 × 50 mm needle was inserted, as precisely as possible, against an acupuncture training gel at a depth of 15 mm. After explaining how to check the distance using their fingers as indicators and how to use a guide piece to check for depth, the students were instructed to train independently for two weeks. Error distance of the acupuncture depth was evaluated before the training (beginning of the training) and at training 1 (training for 7 days), training 2 (training for 14 days/end of training), and post-training (28 days after training 2). [Results] The error distance (absolute value) from 15 mm in training 1, training 2, and post-training decreased significantly compared with those before the training. The error distance was not significantly different between post-training and training 2. [Conclusion] After two weeks of acupuncture training, the error distance decreased significantly, suggesting that this technique was retained after 28 days of completing the training.