According to an embodiment of the present disclosure, a computer program stored in a computer readable storage medium is disclosed. The computer program includes instructions for causing one or more processors to estimate bone age from a bone image, and the instructions include: estimating a RUS score for each of one or more partial bone images using a partial bone RUS score estimation model comprising one or more layers, and wherein the one or more partial bone images are generated from a whole bone image; and estimating bone age corresponding to the whole bone image using one or more RUS scores estimated for each of the one or more partial bone images, in which the partial bone RUS score estimation model is trained by using a labeled partial bone image as training data, and is trained by adjusting feature values calculated from the one or more layers.