Objective　To explore the effects of 2+1 PAD class based on online course in medical statistics undergraduate teaching. Methods A total of 326 clinical undergraduates who took medical statistics in the spring term of 2017 were randomly divided into experimental group (n=186) and control group (n=140). Students in the experimental group were taught by 2+1 teaching method

which included self-study on line

classroom teaching

discussion and so on. While students in the control group were taught traditionally. Feedbacks about the teaching progress and effects from the students in the two groups were compared. SAS 9.4 was used for quantitative data description

t-test and rank sum test. Results　according to the students

the online-based 2+1 teaching method paid more attention to interdisciplinarity than traditional method (P＜0.01)

and the new teaching method was more beneficial for the improvement of students' capacity (P=0.008) and more conducive for students to engaging in scientific research (P=0.012). Students in the experimental group had higher overall satisfaction scores (P＜0.01) and better ability for solving comprehensive problems (P＜0.01). Conclusion　The 2+1 PAD class teaching model based on online courses has more advantages than traditional teaching methods does

which should be recommended and adopted in undergraduate teaching.