Ziping Ye is a postdoctoral researcher at the Prevention Policy Modeling Lab in the Department of Health Policy at Stanford. Her research focuses on the development of decision making models for disease prevention programs.
Previously, Dr Ye served as an assistant professor at the School of Public Administration at Hainan University, where she conducted research on cost-effectiveness thresholds, health outcomes studies, and health burden surveys. Dr Ye received her Ph.D. in Pharmacy Administration from Shenyang Pharmaceutical University with a specialization in Pharmacoeconomics. She is also a self-taught R programmer.

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All Publications

  • Willingness to Pay for One Additional Quality Adjusted Life Year: A Population Based Survey from China. Applied health economics and health policy Ye, Z., Abduhilil, R., Huang, J., Sun, L. 2022; 20 (6): 893-904


    The aim of this study was to estimate the population's willingness to pay (WTP) for an additional quality-adjusted life-year (QALY) in China.The WTP for an additional QALY (WTP/Q) was estimated using a contingent valuation survey with quota sampling and snowball sampling, using a pre-designed questionnaire with 18 hypothetical scenarios. The change in health state was depicted by the EQ-5D-5L. The questionnaires were completed by telephone and face-to-face interviews. Two-part regression models were used to test validity and how different factors affect WTP/Q.A total of 2008 people participated in this survey and provided 3265 WTP responses for further analysis. The average WTP/Q for the entire sample is 113,120 Renminbi (RMB) (USD 16,884), which is 1.75 times the gross domestic product (GDP) per capita. For the quality-of-life improvement scenarios, the mean WTP/Q is RMB 78,907 (USD 11,777, 1.22 times GDP per capita), which is significantly lower than the life extension scenarios (RMB 177,761, USD 26,531, 2.76 times GDP per capita). Age was found to be negatively related to positive WTP. Educational level was positively related to the probability of reporting positive WTP and the level of WTP/Q. Although the EQ-5D-5L utility scores of respondents did not prove to be statistically significant determinants of WTP/Q, the two dimensions of EQ-5D-5L, pain/discomfort and anxiety/depression, had an impact on WTP/Q. In addition, WTP/Q was higher when the health outcome had a 50% probability of occurring than when the health outcome was 100% certain. WTP/Q was higher when a lower health gain was presented to the respondent.This study provides empirical evidence of the monetary value of an additional QALY from a sample of the Chinese population. In addition, a higher threshold for end-of-life therapies should be considered.

    View details for DOI 10.1007/s40258-022-00750-z

    View details for PubMedID 35934772

    View details for PubMedCentralID PMC9358064

  • A systematic review and meta-regression of studies eliciting willingness-to-pay per quality-adjusted life year in the general population. Expert review of pharmacoeconomics & outcomes research Ye, Z., Ma, J., Liu, F., Wang, C., Zhou, Z., Sun, L. 2022; 22 (1): 53-61


    From the demand-side perspective, the monetary value of one additional quality-adjusted life year (QALY) is estimated as willingness-to-pay per QALY (WTPQ). This study aims to summarize the methods and contexts of elicitation of willingness-to-pay per quality-adjusted life year (WTPQ) in the general population and to investigate the heterogeneity of WTPQ estimates.Meta-regression analysis was conducted using Comprehensive Meta-Analysis Software. Sensitivity analyses were undertaken by replacing the lowest and highest 5% and 2.5% of WTPQ by percentiles.33 studies with 102 WTPQ estimates were included. The overall mean and median WTPQ estimates are $1,280,002 and $44,072, respectively. The meta-regressions demonstrated that types of health gain (quality of life or life length) and certainty of health outcomes are statistically significant factors. Furthermore, compared with online interviews, face-to-face interviews tend to yield lower WTPQ. Moreover, the declining trend of QALY gains and positive effect with statistical significance of the sample age were also noticed.For valid and representative values of WTPQ, future researchers should therefore take into consideration various scenarios and investigate both health gain with certainty and uncertainty, health gain from both life length and quality of life, and different size of QALY gains.

    View details for DOI 10.1080/14737167.2021.1878881

    View details for PubMedID 33464926

  • Release and impact of China's "Second List of Rare Diseases". Intractable & rare diseases research Tang, M., Yang, Y., Ye, Z., Song, P., Jin, C., Kang, Q., He, J. 2023; 12 (4): 251-256


    On September 18, 2023, the National Health Commission of China officially announced the "Second List of Rare Diseases". This list of 86 rare diseases, drafted in accordance with the "Working Procedures for Drafting the List of Rare Diseases", marks the second release of a rare disease list since the initial list was issued in May 2018. Following the release of the first batch, the Chinese Government introduced various policies to enhance the diagnosis and treatment of rare diseases, to promote the research on, development of, production of, and availability of rare disease medications in China, and to improve medication access for patients with rare diseases. Consequently, this has elevated the level of rare disease diagnosis and treatment, ensuring greater accessibility to treatment for affected individuals. The expansion of the rare disease list through the release of the "Second List of Rare Diseases" will further enhance rare disease management, increase awareness, improve diagnosis and treatment, facilitate the development and availability of more rare disease medications, establish a comprehensive support system for patients with rare diseases, and ultimately benefit a larger number of individuals affected by rare diseases. The definition of rare diseases in China should be refined by explicitly establishing corresponding criteria based on incidence, prevalence, or the number of affected individuals. Additionally, the mechanism for removal of diseases from rare disease lists should be enhanced, and prompt adjustments should be made regarding diseases that do not align with the selection principles of the list, taking into consideration environmental changes.

    View details for DOI 10.5582/irdr.2023.01086

    View details for PubMedID 38024584

    View details for PubMedCentralID PMC10680157

  • The initiation, exploration, and development of hospital-based health technology assessment in China: 2005 ‒ 2022. Bioscience trends Tang, M., Zhang, X., Ye, Z., Feng, L., Yang, Y., Hou, Z., Bai, F., Lin, X., Liu, X., Yang, H., Hu, S., Song, P., He, J. 2023; 17 (1): 1-13


    A hospital-based health technology assessment (HB-HTA) can provide the evidence needed to inform clinical decisions at the administrative level. With the implementation of a new round of medical and health care system reforms in China, such as the abolition of medical mark-ups, adoption of modern hospital management systems, reform of diagnosis related groups (DRGs) payment, and performance evaluations for public hospitals, medical institutions increasingly need HB-HTA. The development of HB-HTA in China can be divided into three phases: An initiation phase (2005-2014), a preliminary exploratory phase (2015-2017), and a rapid development phase (2018-present). HB-HTA has been used to manage medical consumables, medical devices, and medicines, but there are still problems and challenges in terms of concept recognition, the mode of development, and limited professionals and data. To promote and use HB-HTA in developing countries, we have identifies the development paths and recommendations for implementation based on a case study in China, which can be summarized as follows: enhancing the top-level design of HB-HTA, formulating HB-HTA guidelines, further promoting the main ideas of HB-HTA, concentrating on the training of evaluation personnel, establishing an HB-HTA network and paying attention to the flexibility of HB-HTA in the application process, and multi- stakeholder participation.

    View details for DOI 10.5582/bst.2023.01013

    View details for PubMedID 36775343

  • Comparing the monetary value of a quality-adjusted life year from the payment card and the open-ended format. Cost effectiveness and resource allocation : C/E Ye, Z., Liu, F., Ma, J., Zhou, Z., Wang, C., Sun, L. 2021; 19 (1): 45


    The payment card (PC) format and the open-ended (OE) format are common methods in eliciting willingness-to-pay (WTP) of one additional quality-adjusted life year (QALY). The aim of this research is to compare these two formats in eliciting the monetary value of a QALY.A contingent valuation survey was carried out using a pre-designed questionnaire with various hypothetical scenarios. The difference between the PC and the OE formats was evaluated by a two-sample equality test. Furthermore, generalized linear models were carried out to control observed heterogeneity and to test theoretical validity.In total, 461 individuals were involved, among whom 235 (51%) answered the PC question, while 226 (49%) answered the OE question. Excluding zero response, the mean WTP values of these two formats for different scenarios varied dramatically, which was from 13,278 to 280,177 RMB for the PC, 18,119 to 620,913 RMB for the OE. The OE format tended to elicit lower values for less serious condition and higher values for more serious condition. However, equality test of mean and median demonstrated insignificant difference of these two formats for all scenarios. For both OE and PC format, most variables were found to have significant effect on the value of WTP/QALY. Moreover, joint estimation indicated a statistically significant positive effect on the OE results. Further analysis demonstrated that the imbalanced zero response distribution caused the main difference of these two formats.This research indicated insignificantly different WTP/QALY estimates of the PC format and OE format with the grouped data whereas significantly higher estimates of the OE format from the pooled data. These two formats were found to be valid. More research about the difference and the validity of various WTP eliciting methods would be recommended for a robust estimation of WTP/QALY.

    View details for DOI 10.1186/s12962-021-00298-0

    View details for PubMedID 34281574

    View details for PubMedCentralID PMC8287741

  • A head-to-head comparison of EQ-5D-5 L and SF-6D in Chinese patients with low back pain. Health and quality of life outcomes Ye, Z., Sun, L., Wang, Q. 2019; 17 (1): 57


    The comparative performance of the 3-level EuroQol 5-dimension and Short Form 6-dimension (SF-6D) has been investigated in patients with low back pain (LBP). The aim of this study was to explore the performance including agreement, convergent validity as well as known-groups validity of the 5-level EuroQol 5-dimension (EQ-5D-5 L) and SF-6D in Chinese patients with LBP.Individuals with LBP were recruited from a large tertiary hospital in China. All subjects were interviewed using a standardized questionnaire including the EQ-5D-5 L, 36-item Short Form Health Survey (SF-36), the Oswestry questionnaire and socio-demographic questions from June 2017 to October 2017. Agreement was evaluated by intra-class correlation coefficients (ICCs) and Bland-Altman plots. Spearman's rank correlation coefficients were applied to assess convergent validity. For known-groups validity, the Mann-Whitney U test or Kruskal-Wallis H test were used, effect size (ES) and relative efficiency (RE) were also reported. The efficiency of detecting clinically relevant differences was measured by receiver operating characteristic (ROC) curves between pre-specified groups based on Oswestry disability index (ODI), ES and RE statistics were also reported.Two hundred seventy-two LBP patients (age 38.1, 38% female) took part in the study. Agreement between the EQ-5D-5 L and the SF-6D was good (ICC 0.661) but with systematic discrepancy in the Bland-Altman plots. In terms of convergent validity, most priori assumptions were more related to EQ-5D-5 L than SF-6D, but MCS derived from SF-36 was more associated with SF-6D. EQ-5D-5 L demonstrated better performance for most groups except location and general health grouped by the general assessment of health item from SF-36. Furthermore, when we applied ODI as external indicator of health status, the area under the ROC curve for EQ-5D-5 L was larger than that for the SF-6D (0.892, 95% CI 0.853 to 0.931 versus 0.822, 95% CI 0.771 to 0.873), the effect size was 0.63 for EQ-5D-5 L and 0.44 for SF-6D, and it was proved that EQ-5D-5 L was 42% more efficient than SF-6D at detecting differences measured by ODI.Both EQ-5D-5 L and SF-6D are valid measures for LBP patients. Even though these two measures had good agreement, they cannot be used interchangeably. The EQ-5D-5 L was superior to the SF-6D in Chinese low back pain patients in this research, with stronger correlation to ODI and better known-groups validity. Further study needs to evaluate other factors, such as responsiveness and reliability.

    View details for DOI 10.1186/s12955-019-1137-6

    View details for PubMedID 30971265

    View details for PubMedCentralID PMC6458837

  • China issues the National Essential Medicines List (2018 edition): Background, differences from previous editions, and potential issues. Bioscience trends He, J., Tang, M., Ye, Z., Jiang, X., Chen, D., Song, P., Jin, C. 2018; 12 (5): 445-449


    On October 25, 2018, the National Health Commission of China issued the National Essential Medicines List (2018 edition) [NEML (2018)]. The NEML (2018) contains 685 drugs, which consist of 417 chemicals and biological products and 268 Chinese patent medicines. Compared to the 2012 version of the NEML, a total number of 165 drugs were added, representing an increase of 31.7%. The biggest increase (90.9%) is in Chinese patent medicines for surgical use. The NEML (2018) set up the category of pediatric medications for the first time, and 11 cancer drugs were added. The NEML (2018) is characterized by: "basic" to "comprehensive" coverage, it includes both Chinese and Western medicines, it now includes pediatric drugs, and more cancer drugs have been added. There are several issues with the new NEML such as the link between the essential medicines system and the medical insurance system and establishment of firm support for implementation.

    View details for DOI 10.5582/bst.2018.01265

    View details for PubMedID 30473550

  • Comparison of effectiveness of premixed insulin with long-acting insulin in diabetes: evidence from real-world cohort studiessystematic review and meta-analyses INTERNATIONAL JOURNAL OF DIABETES IN DEVELOPING COUNTRIES Ye, Z., Xin, Q., Jiang, X., Sun, L. 2018; 38 (4): 366-374