Identification and evaluation of radiographic interpretation errors among undergraduate dental students

Radiographic interpretation among dental students remains prone to errors due to its subjective nature between individuals. This study aimed to identify types of errors in dental radiograph interpretation and explore their underlying causes. A mixed-methods design was employed, involving fifth- and sixth-year undergraduate dental students from Mahidol University. In the quantitative phase, students completed an online radiographic interpretation test via Cisco Webex Meetings. Errors that occurred during radiographic interpretation were recorded and categorized as incorrect diagnosis, false-positive, and false-negative types. Comparisons were made between the two student groups. In the qualitative phase, students participated in individual Webex interviews, during which they explained their interpretation processes and identifying errors across six radiographs. Thematic analysis was used to explore specific error types and contributing factors. The quantitative phase showed false-negative errors were the most frequent. Fifth-year students made 206 errors (7.92 ± 2.86), while sixth-year students made 172 errors (6.62 ± 3.50). A statistically significant difference was found only in incorrect diagnoses (<i>p</i> = 0.041), with fifth-year students making more such errors. The qualitative phase revealed six types of interpretation errors. Overlooking, inattentional blindness (IAB), and satisfaction of search (SOS) were associated with ineffective visual scanning. Recognition errors arose when abnormalities were detected but not correctly recognized. Prevalence effect and decision-making errors reflected flaws in diagnostic reasoning processes. Contributing factors included external elements (time pressure, clinical information availability, and radiographic indications) and internal elements (knowledge and experience), which affected students' interpretation performance. Interpretation errors occurred throughout different stages and were influenced by individual and contextual factors. Addressing these issues requires explicit teaching of common interpretation errors, promoting systematic search strategies, and fostering cognitive awareness. Integrating didactic content, case discussions, longitudinal training, and reflective exercises can enhance students' clinical reasoning, metacognitive skills, and diagnostic accuracy in radiographic interpretation.