Background: Three medical schools in Indonesia have been collaborating in evaluating the learning process in the current curriculum by administering a collaborative progress test (cPT). The 120 multiple choice questions for cPT was developed by the three schools. This study aimed to assess the validity and reliability of the cPT as a part of curriculum evaluation. Method: The cPT was administered to year 1-5 students. A stratified random sampling based on the student Grade Point Average (GPA) was performed. The construct validity was established by assessing the accordant increase of mean score of cPT to the student year level. Finally, the reliability of the cPT was calculated using Cronbach Alpha coefficient. Result and discussion: A total of 223, 219 and 161 year 1 to 5 students completed the cPT in FM UI, FM UNAND, and FM UNS, respectively. The content and construct validity of the cPT re evident. There was an increase of the mean score from year 1 to 5, either in the pooled data (one way ANOVA F 174.7(4), p<0.001) and in each school (one way ANOVA FMUI F 102.5 (4) p<0.001, FM UNAND F 83.0 (4) p<0.001, FM UNS 28.28(4) p<0.001). The internal consistency of the cPT was very good in the three institutions. Conclusion: The cPT was proven to be a valid and reliable test to measure the increase of knowledge of medical students and was also useful to provide feedback for curriculum evaluation in the three medical schools. Further improvement is required in assuring the test blueprint and the content of the test items.