Feedback is one of the most important tools to improve teaching in medical education. Our aim was to develop an instrument for performance assessment of clinical postgraduate teachers in medical specialties; Medicina Universidad Católica-Postgraduate-14-items (MEDUC-PG14).

Mixed methodology was employed, with a qualitative methodology (interview/focus group) followed by quantitative methodology to arise consensus. After the instrument was generated, psychometrics tests were performed to assess the construct validity by factor analysis and reliability using Cronbach's alpha.

Interviews and focus groups were performed, including experts in medical education, teachers and residents of Postgraduate programs in Medicine, at the Pontificia Universidad Católica de Chile Medical School (PUCMS). From this information, 26 categories were obtained, of which 79 items were proposed. Subsequently, a panel of experts in medical education and postgraduate committee members of PUCMS assessed the degree of importance of each item. A definitive instrument with 14 items was achieved.123 surveys were answered by residents from different programs of medical specialties. Construct validity was carried out. Factor analysis showed three domains present: 1. Teaching and evaluation, 2. Respectful behavior to patients & healthcare team, 3. Providing feedback. The global score was 4.46 ± 0.94 (89% maximum). Based on the results, one of the strengths of the teachers evaluated by their residents was "respectful behaviour" with 4.85 ± 0.42 (97% maximum) and there was room for improvement in aspects related to "providing feedback" with 4.09 ± 1.0 (81.8% maximum). MEDUC-PG14 is highly reliable with an overall Cronbach's alpha coefficient 0.947.

MEDUC-PG14 is a useful and reliable guide for teacher evaluation in programs of medical specialties. Also provides feedback to improve teaching quality of postgraduate clinical teachers and is the first instrument in this field in Latin America.

MEDUC-PG14 is a validated instrument for assessment of clinical postgraduate teachers.

Grant 1120652 from Fondo Nacional de Desarrollo Científico y Tecnológico