Wu et al. BMC Pregnancy and Childbirth (2020) 20:604 https://doi.org/10.1186/s12884-020-03270-7 RESEARCH ARTICLE Open Access Eliciting women’s preference for prenatal testing in China: a discrete choice experiment Liangzhi Wu1,2†, Yanxin Wu3†, Shiqian Zou3,4†, Cong Sun5, Junyu Chen6, Xueyan Li4, Zihang Lin6, Lizhi Guan6, Qing Zeng6, Sihan Zhao6, Jingtong Liang6, Rui Chen5, Zhiwen Hu6, Kingyan Au6, Daipeng Xie6, Xiaomin Xiao1 and Wai-kit Ming1,3,4,7* Abstract Background: Pregnancy tests can be used for the early diagnosis of fetal problems and can prevent abnormal birth in pregnancies. Yet, testing preferences among Chinese women are poorly investigated. Methods: We developed a Discrete Choice Experiment with 5 attributes: test procedure, detection rate, miscarriage rate, time to wait for result, and test cost. By studying the choices that the women make in the hypothetical scenarios and comparing the attributes and levels, we can analyze the women’s preference of prenatal testing in China. Results: Ninety-two women completed the study. Respondents considered the test procedure as the most important attribute, followed by detection rate, miscarriage rate, wait time for result, and test cost, respectively. The estimated preference weight for the non-invasive procedure was 0.928 (P < 0.0001). All other attributes being equal, the odds of choosing a non-invasive testing procedure over an invasive one was 2.53 (95% confidence interval, 2.42–2.64; P < 0.001). Participants were willing to pay up to RMB$28,810 (approximately US$4610) for a non-invasive test, RMB$6061(US$970) to reduce the miscarriage rate by 1% and up to RMB$3356 (US$537) to increase the detection rate by 1%. Compared to other DCE (Discrete Choice Experiment) studies regarding Down’s syndrome screening, women in our study place relatively less emphasis on test safety. Conclusions: The present study has shown that Chinese women place more emphasis on detection rate than test safety. Chinese women place great preference on noninvasive prenatal testing, which indicate a popular need of incorporating noninvasive prenatal testing into the health insurance coverage in China. This study provided valuable evidence for the decision makers in the Chinese government. Keywords: Choice behavior, Women, Discrete choice experiment, Prenatal diagnosis * Correspondence: [email protected] †Liangzhi Wu, Yanxin Wu and Shiqian Zou are joint first authors. 1The Department of Obstetrics and Gynecology, First Affiliated Hospital of Jinan University, Guangzhou, Guangdong, China 3Department of Obstetrics and Gynecology, The First Affiliated Hospital of Sun Yat-sen University, Guangzhou, Guangdong, China Full list of author information is available at the end of the article © The Author(s). 2020 Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated in a credit line to the data. Wu et al. BMC Pregnancy and Childbirth (2020) 20:604 Page 2 of 8 Background the process for shared decision making for the choice of Prenatal testing can be used for early detection of fetal best diagnostic strategy in high-risk pregnancies. abnormalities such as Down syndrome. In China, when Recently, DCE has been widely used in health-care re- a diagnosis of fetal Down syndrome is made, the parents search to understand the patients’ preferences for medi- can opt for continuation or termination of pregnancy. cations and health services [12]. Lean Beulen, et al. Indeed, there’re some areas where termination of preg- applied DCE to estimate the preference of women and nancy complicated with Down syndrome is not allowed, healthcare professionals for prenatal testing in the option maybe different, hence the doctor’s consider- Netherlands [13]. But to our knowledge, no investiga- ation is even more important [1]. Several types of pre- tions has been performed about women’s preferences for natal tests are currently used for this purpose that varies prenatal testing in China. regarding diagnostic performance, invasiveness, and cost. Chorionic villus sampling that involves obtaining a sam- ple from the placenta and amniocentesis test that re- Objectives quires sampling of amniotic fluid by using a hollow To investigate the relative importance of attributes of needle inserted into the uterus are examples of invasive prenatal testing among Chinese women. testing that often provides an accurate diagnosis of po- tential developmental abnormalities in a fetus. Non- Methods invasive prenatal testing (NIPT) that usually rely on a Study population simple blood test from the mother are generally safe and The study was conducted at a university hospital in less costly than invasive prenatal testing but are associ- South China (The First Affiliated Hospital of Sun Yat- ated with higher false negative rates. The research found sen University, Guangzhou, China). We recruited our that the costs are similar as current Down’s screening at sample from women with relatively high-risk pregnancy the cost of £500 per NIPT in the United Kingdom and, who visited the outpatient clinic for prenatal consult- compared with the first trimester combined screening ation between 18 January 2018 and 2 April 2018. Inclu- (measurement of serum markers PAPP-A and β-hCG as sion criteria: 1. At least 18-years-old; 2. Attending the well as first-trimester ultrasound) and integrated screen- first visit for prenatal diagnostic consultation; 3. Gesta- ing (first trimester combined screening and Quad tional period no more than 20 weeks; 4. Ability to com- screening of serum markers (AFP, estriol, hCG, Inhibin ply with the protocol procedures. Exclusion criteria: 1. A)), NIPT have a better Trisomy 21 detection and re- Women with obstetrics related medical history; 2. Those duce euploid fetal loss with a lower total healthcare cost who has gestational period more than 20 weeks. Because in the United States [2, 3]. Women at high risk of having they had previously received a prenatal diagnostic con- babies with genetic abnormalities, usually are offered in- sultation and are not representative for the overall vasive prenatal diagnosis, to ensure higher detection women in China. rates. However, in approximately 1–2% of cases, invasive prenatal testing might result in miscarriage, even when the baby is healthy [4, 5]. Recently, non-invasive test, Discrete choice experiment which is based on the technology to investigate the Cell- The DCE methodology is grounded in multi-attribute free DNA inside a maternal blood sample, has become utility theory in economics. The technique is based on one of the major alternatives of invasive tests and is also the assumption that any commodity (e.g., prenatal diag- available in China, and the accuracy of NIPT was re- nosis test) can be characterized by several key attributes ported with a > 99% for trisomy 21 in both sensitivity and their levels (e.g., test procedure, detection rate, test – and specificity [6 8]. However, in the past decade, it is cost). Therefore, individuals choose among their options not included in the universal coverage, patient have to (e.g., different prenatal testing) by comparing those attri- pay for themselves, and the services are mainly provided butes and levels in hypothetical scenarios. by the private laboratories. NIPT has been introduced for a self-payment option in a national health screening programme for pregnancy Attribute and attribute levels in some jurisdictions in China [9]. However, there is still Possible attributes were identified from a panel of expe- a debate about the optimal choices, considering the rienced directors of gynaecology and obstetrics depart- trade-offs that need to be made among different attri- ment in the First Affiliated Hospital of Sun Yat-sen butes of various prenatal tests, including detection rate, University. And the five attributes are finally selected as the risk of miscarriage, invasiveness, and cost [10, 11]. test procedure, time to wait for results, detection rate, Understanding women’s preferences for different attri- miscarriage and test cost with their different levels. butes of prenatal tests can help physicians to enhance (Table 1). Wu et al. BMC Pregnancy and Childbirth (2020) 20:604 Page 3 of 8 Table 1 Attributes and Levels The test profiles presented in choice questions were cre- Attributes Levels of attributes (regression coding) ated by generating permutations of attribute levels. There Test procedure L1 Invasive: requires collecting samples from are total 360 combinations we could generate based on the amniotic fluid or placenta. level of each attribute. We then created a fractional factorial L2 Non-invasive: only requires a sample of design using Sawtooth that met balance and orthogonality mother’s blood. properties [16]. Balance (i.e., each attribute level appears Time to wait for L1 1 week equally often within an attribute) and orthogonality (i.e., results L2 2 weeks each pair of levels appears equally often across all pairs of L3 3 weeks attributes) ensures minimizing the bias and improves the precision of estimated preferences. We generated 100 ver- Detection rate L1 94% sions of the questionnaire and assigned each respondent to L2 96% a version in a random manner to facilitate achieving bal- L3 98% ance and orthogonality.