Fig. 1

Mutual transition of the seven Markov states in the natural development of cervical cancer. A Markov cycle (one year) of mutual transition is described in the figure. The squares represent the seven different Markov health states. The arrows represent the direction of transition. The Markov state “CANCER” and “DEAD” cannot reverse transfer, and “DEAD” is the absorbing state, it cannot transfer to other states. HPV: HPV infection