Ren Kawamura, Yukinori Harada, Yudai Suzuki, Yumi Otaka, Shogo Hanai, Shinichi Katsukura, Masashi Yokose, Tetsu Sakamoto, Taro Shimizu
Abstract Background Consultations between the General Internal Medicine (GIM) and specialty departments are becoming increasingly crucial to achieving team-based diagnosis and diagnostic excellence; however, there are limited studies on the appropriateness of GIM consultations with specialties. This study aimed to evaluate the proportion of diagnostic consultations from GIM to specialty departments that fulfilled pre-specified, outcome-based criteria for contributing to the establishment of a correct final diagnosis and to identify factors associated with consultations not meeting these criteria. Methods This retrospective, single-center observational study was conducted at a university hospital in Japan. Consultations from the GIM to specialty departments involving patients aged 15 years and older between January 1, 2021 and December 31, 2021 were analysed. The primary outcome was the proportion of diagnostic consultations fulfilling these pre-specified, outcome-based criteria. Factors associated with consultations not meeting these criteria were also analysed. Results In total, 610 consultations for 454 patients were included. Diagnostic consultations accounted for 352 cases (57.7%), among which 229 cases (65.1%) fulfilled these criteria, while 123 cases (34.9%) did not. Consultations not meeting these criteria were associated with the following factors: difficulty in diagnosis at the time of consultation because of undifferentiated symptoms and findings in 41 cases (33.3%), inadequate test implementation and interpretation in 39 cases (31.7%), and insufficient patient information in 12 cases (9.8%). Conclusion Approximately 30% of diagnostic consultations from GIM to specialty departments did not fulfill these pre-specified, outcome-based criteria. Among consultations not meeting these criteria, potentially modifiable factors included inadequate diagnostic test implementation or interpretation and insufficient patient information, whereas approximately one-third involved diagnostic difficulty at the time of consultation because of undifferentiated symptoms and findings. Future efforts should focus on improving diagnostic test implementation and interpretation and on identifying diagnostically difficult cases that can be safely managed by GIM with continued assessment before immediate specialist consultation.