ESAT, Center for Processing Speech and Images, KU Leuven, Leuven, Belgium.
Department of Diagnostic Sciences and Radiology, Ghent University, Ghent, Belgium.
J Forensic Sci. 2024 May;69(3):919-931. doi: 10.1111/1556-4029.15473. Epub 2024 Jan 30.
Dental age estimation, a cornerstone in forensic age assessment, has been extensively tried and tested, yet manual methods are impeded by tedium and interobserver variability. Automated approaches using deep transfer learning encounter challenges like data scarcity, suboptimal training, and fine-tuning complexities, necessitating robust training methods. This study explores the impact of convolutional neural network hyperparameters, model complexity, training batch size, and sample quantity on age estimation. EfficientNet-B4, DenseNet-201, and MobileNet V3 models underwent cross-validation on a dataset of 3896 orthopantomograms (OPGs) with batch sizes escalating from 10 to 160 in a doubling progression, as well as random subsets of this training dataset. Results demonstrate the EfficientNet-B4 model, trained on the complete dataset with a batch size of 160, as the top performer with a mean absolute error of 0.562 years on the test set, notably surpassing the MAE of 1.01 at a batch size of 10. Increasing batch size consistently improved performance for EfficientNet-B4 and DenseNet-201, whereas MobileNet V3 performance peaked at batch size 40. Similar trends emerged in training with reduced sample sizes, though they were outperformed by the complete models. This underscores the critical role of hyperparameter optimization in adopting deep learning for age estimation from complete OPGs. The findings not only highlight the nuanced interplay of hyperparameters and performance but also underscore the potential for accurate age estimation models through optimization. This study contributes to advancing the application of deep learning in forensic age estimation, emphasizing the significance of tailored training methodologies for optimal outcomes.
牙龄评估是法医学年龄评估的基石,已经得到了广泛的尝试和验证,但手动方法受到繁琐和观察者间变异性的限制。使用深度迁移学习的自动方法面临数据稀缺、训练不佳和微调复杂性等挑战,因此需要强大的训练方法。本研究探讨了卷积神经网络超参数、模型复杂度、训练批次大小和样本数量对年龄估计的影响。在一个包含 3896 张全景片(OPG)的数据集上,对 EfficientNet-B4、DenseNet-201 和 MobileNet V3 模型进行了交叉验证,训练批次大小从 10 增加到 160,以 2 的倍数递增,以及此训练数据集的随机子集。结果表明,在完整数据集上使用批量大小为 160 训练的 EfficientNet-B4 模型表现最佳,在测试集上的平均绝对误差为 0.562 岁,明显优于批量大小为 10 时的 1.01 的 MAE。增加批量大小可显著提高 EfficientNet-B4 和 DenseNet-201 的性能,而 MobileNet V3 的性能在批量大小为 40 时达到峰值。在训练中使用较小的样本量也出现了类似的趋势,但它们不如完整模型表现出色。这突显了在使用完整 OPG 进行年龄估计时,超参数优化在采用深度学习方面的关键作用。研究结果不仅突出了超参数和性能之间的细微相互作用,还强调了通过优化实现准确年龄估计模型的潜力。本研究为推进深度学习在法医年龄估计中的应用做出了贡献,强调了为获得最佳结果而定制训练方法的重要性。