Reliability and Validity of the Contingent Valuation Method for Estimating Willingness to Pay: A Case of In Vitro Fertilisation.

BACKGROUND: The contingent valuation (CV) method is an alternative approach to typical health economic methods for valuing interventions that have both health and non-health outcomes. Fertility treatment, such as in vitro fertilisation (IVF), fall into this category because of the significant non-health outcomes associated with having children. AIM: To estimate the general population's willingness to pay (WTP) for one cycle of IVF and one year of IVF treatment, and to test the reliability and validity of a CV instrument. METHODS: Three online CV surveys were administered to a total of 1870 participants from the Australian general population using an ex-post perspective, that is, they assumed they were infertile and needed IVF to conceive a child. Participants answered questions with starting point WTP bids of 2018 Australian dollars (AU$) 4000 or $10,000 for the cost of one IVF cycle, and treatment success rates of 10%, 20% and 50% per IVF cycle. Tests for reliability, internal construct validity, starting point bias, and external validity were performed. RESULTS: Depending on the success rate and the starting point WTP bid, the mean WTP for one IVF cycle ranged from $6135 to $13,561, while the mean WTP for one year of IVF treatment varied from $17,080 to $31,006. The CV method was reliable and satisfied internal construct and external criterion validity. However strong starting point bias was evident, rendering the mean WTP values highly imprecise. CONCLUSION: The CV method holds promise for eliciting the value of interventions, such as fertility treatment, that have significant health and non-health outcomes. Survey instruments that prevent starting point bias are essential. Comparing the results of CV methods to other value elicitation methods is needed to confirm convergent validity.

Assisted reproductive technology (ART) cumulative live birth rates following preimplantation genetic diagnosis for aneuploidy (PGD-A) or morphological assessment of embryos: A cohort analysis.

BACKGROUND: Preimplantation genetic diagnosis for aneuploidy (PGD-A) for all 24 chromosomes improves implantation and clinical pregnancy rates per single assisted reproductive technology (ART) cycle. However, there is limited data on the live-birth rate of PGD-A over repeated cycles. AIM: To assess the cumulative live-birth rates (CLBR) of PGD-A compared with morphological assessment of embryos of up to three 'complete ART cycles' (fresh plus frozen/thaw cycles) in women aged 37 years or older. MATERIALS AND METHODS: A retrospective cohort study of ART treatments undertaken by ART-naïve women at a large Australian fertility clinic between 2011 and 2014. Cohorts were assigned based on the embryo selection method used in their first fresh cycle [PGD-A, n = 110 women (PGD-A group); morphological assessment of embryos, n = 1983 women (control group)]. CLBR, time to clinical pregnancy and cycles needed to achieve a live birth were measured over multiple cycles. RESULTS: Compared to the control group, the PGD-A group achieved a higher per cycle live-birth rate (14.47% vs 9.12%, P < 0.01), took a shorter mean time to reach a clinical pregnancy leading to a live-birth (104.8 days vs 140.6 days, P < 0.05) and required fewer cycles to achieve a live-birth (6.91 cycles vs 10.96 cycles, P < 0.01). However, after three 'complete ART cycles', the CLBR was comparable for the two groups (30.90% vs 26.77%, P = 0.34). CONCLUSION: This is the first study to assess the effectiveness of PGD-A over multiple ART cycles. These real-world findings suggest that PGD-A leads to better outcomes than using morphological assessment alone in women of advanced maternal age.

Socio-economic disparities in access to assisted reproductive technologies in Australia.

Women from disadvantaged socio-economic groups access assisted reproductive technology treatment less than women from more advantaged groups. However, women from disadvantaged groups tend to start families younger, making them less likely to suffer from age-related subfertility and potentially have less need for fertility treatment. Whether socio-economic disparities in access to assisted reproductive technology treatment persist after controlling for the need for treatment, has not been previously explored. This population based study demonstrates that socio-economic disparities in access to assisted reproductive technology treatment persist after adjusting for several confounding factors, including age at first birth (used as a measure of delayed childbearing, hence a proxy for need for fertility treatment), geographic remoteness and Australian jurisdiction. Assisted reproductive technology access progressively decreased as socio-economic quintiles became more disadvantaged, with a 15.8% decrease in access in the most disadvantaged quintile compared with the most advantaged quintile after controlling for confounding factors. The adjusted rate of access to assisted reproductive technology treatment also decreased by 12.3% for women living in regional and remote areas compared with those in major cities. These findings indicate that financial and sociocultural barriers to assisted reproductive technology treatment remain in disadvantaged groups after adjusting for need.

The clinical effectiveness of preimplantation genetic diagnosis for aneuploidy in all 24 chromosomes (PGD-A): systematic review.

STUDY QUESTION: Is preimplantation genetic diagnosis for aneuploidy (PGD-A) with analysis of all chromosomes during assisted reproductive technology (ART) clinically and cost effective? SUMMARY ANSWER: The majority of published studies comparing a strategy of PGD-A with morphologically assessed embryos have reported a higher implantation rate per embryo using PGD-A, but insufficient data has been presented to evaluate the clinical and cost-effectiveness of PGD-A in the clinical setting. WHAT IS KNOWN ALREADY: Aneuploidy is a leading cause of implantation failure, miscarriage and congenital abnormalities in humans, and a significant cause of ART failure. Preclinical evidence of PGD-A indicates that the selection and transfer of euploid embryos during ART should improve clinical outcomes. STUDY DESIGN, SIZE AND DURATION: A systematic review of the literature was performed for full text English language articles using MEDLINE, EMBASE, SCOPUS, Cochrane Library databases, NHS Economic Evaluation Database and EconLit. The Downs and Black scoring checklist was used to assess the quality of studies. Clinical effectiveness was measured in terms of pregnancy, live birth and miscarriage rates. PARTICIPANTS/MATERIALS, SETTINGS, METHODS: Nineteen articles meeting the inclusion criteria, comprising three RCTs in young and good prognosis patients and 16 observation studies were identified. Five of the observational studies included a control group of patients where embryos were selected based on morphological criteria (matched cohort studies). MAIN RESULTS AND ROLE OF CHANCE: Of the five studies that included a control group and reported implantation rates, four studies (including two RCTs) demonstrated improved implantation rates in the PGD-A group. Of the eight studies that included a control group, six studies (including two RCTs) reported significantly higher pregnancy rates in the PGD-A group, and in the remaining two studies, equivalent pregnancies rates were reported despite fewer embryos being transferred in the PGD-A group. The three RCTs demonstrated benefit in young and good prognosis patients in terms of clinical pregnancy rates and the use of single embryo transfer. However, studies relating to patients of advanced maternal age, recurrent miscarriage and implantation failure were restricted to matched cohort studies, limiting the ability to draw meaningful conclusions. LIMITATIONS, REASONS FOR CAUTION: Relevant studies may have been missed and findings from RCTs currently being undertaken could not be included. WIDER IMPLICATIONS OF THE FINDINGS: Given the uncertain role of PGD-A techniques, high-quality experimental studies using intention-to-treat analysis and cumulative live birth rates including the comparative outcomes from remaining cryopreserved embryos are needed to evaluate the overall role of PGD-A in the clinical setting. It is only in this way that the true contribution of PGD-A to ART can be understood.