FormalPara Key Points for Decision Makers

The observation of a lack of voluntary quality disclosure can reflect suboptimal quality standards in healthcare.

Legislation requiring mandatory disclosure relating to treatment quality could be a non-market solution to the problem of inadequate quality standards in some segments of the healthcare sector where patients are responsive to such disclosure.

Care must be taken when designing such measures to avoid adverse incentives.

The role of patients in verifying and improving the accountability of disclosure should be promoted, especially with the increasing availability of digital platforms for quality review and information sharing.

1 Introduction

The role of evidence-based medicine (EBM) in modern medical professions remains controversial. Growing concerns relating to the quality of evidence along with growing practices of EBM (for example, Djulbegovic and Guyatt [1] summarised the progress in EBM during the last quarter century) raise a valid question as to whether the practice of EBM ultimately improves the quality of patient care (see, for example, a recent debate by Djulbegovic et al. [2, 3] and Mondoux and Shojania [4]). This paper aims to provide an economic perspective when evaluating the role of EBM in delivering treatment quality. I highlight that economic incentives in the context of a particular type of market failure—asymmetric information (which takes place when information relating to treatment quality is not available to patients before purchasing the treatment)—are highly relevant to the observation and understanding of the lack of clinics’ disclosure of reliable evidence (relating to treatment quality) in the practice of EBM.

A market with low transparency of pre-purchase quality information available to buyers may discourage high-quality sellers from serving in this market. This is because the presence of low-quality sellers (taking the advantage of pooling with high-quality sellers) adversely affects uninformed buyers’ perception of the ‘average’ quality for which they are or would be willing to pay. The ultimate result could be that there are a large number of low-quality sellers who have the incentive to withhold evidence/information relating to their own quality; in other words, low-quality provision associated with a lack of reliable evidence.

In the paper, the above and related economic incentives are illustrated in detail based on a case study of the UK fertility sector. I focus on the UK fertility sector because there are growing concerns relating to the observation that certain treatments, especially add-on treatments,Footnote 1 in the sector are not always based on reliable evidence (see, for example, discussions by Heneghan et al. [5]). Concerned that certain in vitro fertilisation (IVF) clinic practices may be preventing or inhibiting patients from making informed choices, the Competition and Markets Authority (CMA), the UK’s primary competition and consumer authority, published in November 2020 a draft guidance [6] for UK fertility clinics on consumer law with the purpose of helping fertility clinics understand and comply with their existing obligations under consumer law. At the time of writing, the CMA has not yet ruled out possible law enforcement actions against fertility clinics. The case therefore allows us to better understand possible reasons for the lack of reliable evidence in practice (Sects. 2 and 3) and possible ways to address it (Sect. 4).

Following Lambert [7], I consider EBM as “a set of techniques and practices squarely to the deployment of statistical measurements of outcome derived from population research”.Footnote 2 For the purpose of the paper (relating to quality incentives and outcomes), evidence when referred to as EBM is used to specifically focus on measured quality outcomes relating to treatment effectiveness and safety.

2 A Review of Economic Evidence Relating to Quality Provision and Voluntary Quality Disclosure in the Context of Asymmetric Information

As consumers, we often have to purchase products/services without necessarily having the information to judge their quality prior to purchase. Examples would be healthcare services or durable goods. Sellers may know the quality of the item they sell but it may be in their interest to withhold that information. It is a well-established principle of economics that such markets associated with the market failure of asymmetric information (e.g. sellers have more information than buyers relating to quality), could suffer from the consequence of low-quality provision [8, 9]. This is explained as follows using the example of healthcare clinics.

Patients do not know the quality of a treatment provided by a clinic before they undergo the treatment. They have a general idea about the expected quality (such as the average success rate) of the clinic as well as that of the sector. Based on such an expectation, they will decide how much they are willing to pay for such a perceived ‘average’ treatment. If we have a lot of low-quality clinics providing treatments with relatively low success rates, it will lower the patients’ expectation of success rates and therefore their willingness to pay. If patients’ willingness to pay is sufficiently lowered, high-quality clinics that incur more costs and investments to provide more successful treatments may decide not to provide their service in this market as the expected price is not high enough to cover their costs. Therefore, high-quality clinics are driven out of the market by the presence of a large number of low-quality clinics in the market who find it in their interest to hide quality. This results in lower average quality provision associated with a lack of quality-related evidence available to patients.

The above simplified illustration of an Akerlof-type of market failure explains intuitively why quality is likely to be underprovided in markets with asymmetric information. However the scenario described above is not representative of the real-world cases where buyers do not know the average quality of the goods/services ex ante and they may not even be able to observe or assess the quality ex post. Indeed, there is a large body of literature focusing on a specific type of goods whose quality cannot be evaluated in normal use.Footnote 3 In particular, consider an expert (e.g. a doctor) who knows more about the type of good or service the buyer (e.g. the patient) needs than the buyer themselves.Footnote 4 The expert seller is able to identify the treatment that fits a buyer’s need best by performing a diagnosis (hence this type of market is also referred to as treatment and diagnosis markets). They can then provide the right quality and charge for it, or they can exploit the informational asymmetry by defrauding the buyer. The literature (see comprehensive reviews provided by Dulleck and Kerschbamer [12] and Balafoutas and Kerschbamer [13]) establishes that dishonest seller behaviour can arise in several dimensions (rather than just the under provision of quality mentioned above), including (1) buyers being overcharged for the actual treatment they receive but cannot observe; (2) buyers being overtreated with unnecessary treatment, which buyers do not know if they need; and (3) buyers being undertreated with an inadequate treatment (the underprovision of quality mentioned above), the outcome of which buyers cannot observe or verify to hold the seller accountable.Footnote 5

In addition, diagnoses are often imprecise and require a certain amount of effort invested by the expert (with healthcare services being a prime example of such a situation). Diagnosis effort is often not observable to the buyers. These facts could further worsen the problem of asymmetric information illustrated here. For instance, how can the expert be induced to perform the costly but unobservable diagnosis, and how can the expert be induced to reveal the diagnosis outcome truthfully?Footnote 6

In the healthcare setting, it is clear that to assess the quality of the treatment, patients need to have information regarding what treatment they need, what treatment they receive, and the treatment outcome. The above economic evidence indicates clinics have a clear lack of incentives to acquire and disclose such information.

Incentives for quality disclosure require further explanation. Consider a seller with private (but verifiable) information about the quality of their product. Economic theory predicts sellers do have incentives to voluntarily disclose such quality information, even if it is unfavourable information, if certain conditions are satisfied [17,18,19]. The intuition behind this is as follows.

For sellers, voluntary disclosure has the benefit of correcting buyers’ perception of the product quality. If the seller does not disclose their private information about the product quality, the most they can charge is the value of an average-quality product. Thus, if the actual value of the product is higher than that of an average product, the seller would choose to disclose quality. The consumers, in turn, revise downwards their estimate of the quality of products whose quality is not disclosed by sellers. This causes more types of sellers to disclose, and the process repeats itself until all types disclose (‘unravelling’). It follows that all sellers (high- or low-quality type) will voluntarily disclose quality, implying that costly government-mandated disclosure is inefficient and unnecessary.

The above ‘unravelling’ should in principle resolve the quality problem associated with asymmetric information. However, a number of strong assumptions are required for the ideal result to hold. One could view those factors that violate the assumptions as forming a quality threshold. If firms’ quality level (even though above average) is below the threshold, they may decide not to voluntarily disclose quality unilaterally. Such factors may be the cost of acquiring or verifying quality information [17, 20], or whether consumers understand or perceive nondisclosure as a signal of the lowest quality [21, 22], how many firms there are in the market [23, 24], how firms compete with each other [25] and how competitive they are at setting their prices [26].

To understand whether a lack of voluntary evidence disclosure is likely to occur in practice and how that is associated with clinics’ incentives relating to quality improvement, I look at a case study of the UK IVF sector. I first document some stylised observations based on the reported results from interviews and a survey conducted by the CMA [27] and the sector regulator Human Fertilisation and Embryology Authority (HFEA) [28]. Based on the stylised observations, I then illustrate the economic evidence reviewed above in the context of the UK IVF sector to understand the practical implications of lack of evidence disclosure on treatment quality. I focus on two very important dimensions of quality, i.e. the effectiveness and safety of treatments, as they are confirmed to be the most important quality attributes of IVF treatment by the response data reported by the CMA [27] and HFEA [28].

3 A Case Study: The UK In Vitro Fertilisation Sector

Every year around 70,000 cycles of IVF treatment take place in the UK [29]. The UK fertility market is worth around £320 million annually and has enjoyed steady growth over recent years [6, 30]. Treatment in the private sector continues to grow. The share of IVF cycles funded by the NHS has declined across most English regions over recent years, with 65% of treatment cycles in 2018 in England being self-funded [29]. I focus the following analysis on private fertility clinics that provide IVF treatment to self-funded patients.

3.1 Stylised Observations

The stylised observations in the UK fertility sector are based on the reported results from the national patient survey data collected in 2018 by the HFEA [28] and findings reported in the CMA’s research report [27] when developing the draft guidance [6] for fertility clinics and patients mentioned above. Further details relating to the two sources of information are explained in Appendix 1, with an overview of patient responses to treatment quality in Table 1 of the Appendix 1.

3.1.1 Observation 1: Incomplete and Sometimes Misleading Evidence Disclosure of Success Rates

UK IVF clinics often advertise the headline success rates by using the measure that gives them the highest success rate. With the revised code of conduct issued by the HFEA [31], the reporting of success rates has become more comprehensive. However, as reported by the CMA [27], a small group of respondents stressed the difficulties they experienced when comparing success rates for different clinics due to a perceived lack of consistency in how success rates were reported. Another small group questioned the accuracy of success rates, based on greater experience of IVF treatment and/or a more informed perspective on statistics. Many objected to clinics presenting success rates based on pregnancies, as respondents were more interested in those based on live births.

One prominent response relating to the information disclosure of success rates emerging from the survey conducted by the HFEA [28] is the lack of information on personalised chance of success. The CMA [27] confirms that many respondents reported that success rates of IVF treatment were generally discussed in generic rather than personalised terms. Although a few reported discussing their personal chance of success, most did not, and the specific basis for the individual discussions reported (i.e. whether test results, scans, age and previous history of IVF and any specific fertility issues) is unclear. For those with unsuccessful experiences, the HFEA [28] responses point out that overestimated personal success rates are misleading (see quoted responses in Figs. 1 and 2 in Appendix 1).

3.1.2 Observation 2: Incomplete Evidence Disclosure of Effectiveness or Safety of Add-On Treatments and Fertility Drugs

The CMA [27] recognises that there is a lack of consistency with respect to conveying information about the evidence for the effectiveness of add-on treatments to patients, that is, informing them there is little or no robust evidence, and of the risks where appropriate. Meanwhile, patient responses documented by both the CMA [27] and HFEA [28] indicate that some patients demand more evidence-based estimates of the effectiveness of certain treatments (see quoted responses in Fig. 3 in Appendix 1).

Respondents (interviewed by the CMA [27]) who were interested in what they described as ‘medication-light IVF’ treatment sometimes felt their choice was limited and that they had to work harder to find suitable clinics. It is worth pointing out that clinics’ incentives are not typically aligned with those of the patients. If heavy use of drugs can increase the number of eggs retrieved, it means treatment is more likely to continue. In addition, the phenomenon of expensive fertility drugs in the UK provided by clinics that are often linked with dedicated distributors is consistently reported among respondents interviewed by the CMA [27]. High profit margins associated with these fertility drugs could drive overprescription of such drugs. The result is that some patients may end up being overprescribed with such drugs, incurring high costs, possible adverse effects or long-term health risks (imposed on the mother, children, or both).

3.2 Incomplete Evidence Disclosure in the UK Fertility Sector May Well Reflect Inadequate Quality Provision

If there were clinics providing distinctively high-quality treatments in this sector, there should be great incentives for them to unilaterally and voluntarily reveal more treatment evidence, such as personalised success rate, to demonstrate their distinctively high quality. Linking to the economic evidence discussed earlier, I provide a number of reasons for this.

First, patients in this sector are largely responsive to quality information. Treatment effectiveness of a given location is the top determining factor considered by patients when choosing a clinic, whereas cost as a determining factor is quite far down the list in comparison (confirmed both by the HFEA [28] and CMA [27]; also see Table 2 in Appendix 1). In fact, as some of the responses quoted above indicate (see Figs. 1, 2 and 3 in Appendix 1), patients indeed demand to know their personal chance of success as a measure of treatment quality. This is consistent with existing evidence provided by Bundorf et al. [32] that suggests patients are responsive to quality report cards when choosing among providers in the fertility sector in the US.

Second, cost associated with acquiring and verifying quality-related evidence is not prohibitively high. Whereas randomised clinical trials could be time-consuming, routinely collected data by clinics could also reveal useful information about the treatment quality at a given clinic. It may incur some cost to analyse such data to assess, at least to some extent, the effectiveness or safety of the existing treatments and drugs, but overall the cost of a more complete quality disclosure (than what is currently disclosed) is not prohibitively high. Based on patients’ responses documented by the CMA [27] and HFEA [28], even evidence based on routinely collected data is not typically provided to inform patients of potential effectiveness or risk associated with treatments.

One may argue that, even if clinics are not directly disclosing evidence, they could indirectly signal high-quality services (especially if such evidence is difficult to verify), for instance through warranty, pricing, advertisement or research and development [33, 34]. A quick search of the UK IVF clinics’ websites reveals that little to no information is available to indicate that these IVF clinics are investing competitively in R&D to differentiate their treatments. The author is not aware of any clinics in the UK that provide any warranty related to treatment outcomes or safety. There is also very little evidence to suggest that price differences among clinics are signalling distinctive quality levelsFootnote 7.

Therefore, a plausible explanation for incomplete evidence disclosure observed in the sector is that it reflects a relatively low or inadequate level of quality provision in terms of treatment effectiveness and safety. Indeed, the reported live birth rate data strongly indicates there is great room for improvement in terms of treatment effectiveness, especially considering the relatively high cost associated with private IVF treatments in the UK. Note that for every 10 embryos transferred, on average in the UK in 2018, about 2.3 embryos survive and develop into live birth [29].

Given that clinics fail to disclose reliable evidence fully and voluntarily in practice, especially if the quality of treatment is not sufficiently high, a question that naturally arises is ‘Could it be a possible mechanism to facilitate the acquisition and revelation of more evidence if clinics are required by law to disclose such evidence unilaterally, in the absence of sufficient economic incentives on clinics to voluntarily disclose such evidence?’ I aim to address this question next.

In the CMA’s draft guidance [6], various standards of mandatory information disclosure have been established for this sector. The information disclosure standards are primarily concerned about transparency, comparability and consistency of the information relating to clinics’ treatment costs. The draft guidance makes a much less explicit requirement for fertility clinics to disclose quality-related information, including evidence on effectiveness and risk associated with add-on treatments.

4 Legislating Mandatory Evidence Disclosure

4.1 A Review of Economic Evidence Relating to the Effect of Mandatory Quality Disclosure on Firms’ Quality Provision

Mandatory quality disclosure is extensively examined in the economics literature as a non-market solution to problems associated with quality provision in the context of asymmetric information. Theoretical evidence of the impact of mandatory quality disclosure on quality provision is not clear-cut and suggests that the impact depends on the reason for incomplete disclosure as mentioned earlier. For instance, when non-disclosure is innocent and due solely to disclosure costs, mandatory disclosure is socially excessive [35]. Mandatory disclosure of information, but not acquisition of information, may motivate sellers to reduce information acquisition [36, 37].

It should be noted studies in this body of theoretical literature typically maintain the assumption that firms’ quality is given, overlooking the possibility that quality disclosure can incentivise firms to choose high-quality product. Therefore, the benefit of mandatory quality disclosure could be underestimated in the evidence mentioned above. Taking into account quality incentives, Fishman and Hagerty [21] show that firms’ incentives to improve quality could be higher under the law, even if very few consumers understand the disclosure. However, limited attention of buyers means greater disclosures of multiple dimensions could reduce the average accuracy of buyers’ perception and that a complex balance of considerations of discourse of different dimensions is needed [23].

There is fairly strong empirical evidence from a variety of markets, indicating that mandatory disclosure could improve quality standards (e.g. Mathios [38] provides evidence in the food sector, while Bennear and Olmstead [39] provide evidence relating to drinking-water suppliers). In the healthcare sector, consistent with the theoretical evidence mentioned above, the empirical evidence demonstrates that consumers have different receptiveness to mandatory quality reports [40,41,42], implying the effect on quality provision may vary depending on consumers’ responsiveness.

Another potential benefit of mandatory disclosure that is less studied (theoretically or empirically) is the longer-term effects associated with better consumer selection and matching of products with more complete information [43], especially with the rapid development of information and communication technology (ICT) and digital platforms to dissipate information among consumers. Barriers to search or switch clinics could hinder patients from finding the best-quality clinic and make patients captive to a certain degree, creating little incentives on clinics with respect to exercising the amount of effort expected by the patient to deliver the individual outcome. By breaking down such barriers, quality disclosure may drive out low-quality  clinics, encourage entry by high-quality competitors, or incentivise existing clinics to improve quality. Such an effect may be achieved with the presence of a proportion of consumers who are empowered by pre-purchase quality information to improve matching and quality selection, generating positive externality on consumers who ignore quality disclosure.

Illustrated in the case of the UK fertility sector, if quality provision is indeed a problem in the context of asymmetric information as established earlier, and considering patients are responsive to and engaging with evidence disclosure, legislation requiring mandatory evidence disclosure is likely to improve the standard of quality provision. In addition, quality information disclosure may help break down any barriers patients face to search and switch clinics (e.g. initial consultation fees typically cost around £200 in London, paid by patients to find a match; clinic locations as identified by the CMA [27] and Table 2 in Appendix 1).

However, the literature in economics suggests that inappropriate measures of mandatory information disclosure could create adverse incentives on the firms, resulting in not only no improvement in quality but even harm to consumers. Therefore, care must be taken when designing such measures. An extensive list of examples in the healthcare and education sector are reviewed by Dranove and Jin [44]. Based on the evidence presented in this body of literature, in the following I explain, in the context of the UK fertility sector, the implications of implementing mandatory evidence disclosure on the practice of EBM. In particular, I highlight the role of regulators in setting the standards of disclosed evidence to improve interpretability, and patients’ role in engaging with clinics and verifying such evidence to improve accountability.

5 The Implications of Implementing Mandatory Evidence Disclosure for the Practice of Evidence-Based Medicine in the UK Fertility Sector

Mandatory disclosure may fail to achieve any desired impact on treatment quality if the evidence disclosed is very difficult for patients to interpret or if the information is simply irrelevant. Take success rate in the fertility sector as an example. The success rate for a female patient aged 30 years with male infertility factors may have little relevance to another female patient aged 40 years with a completely different infertility issue. How can the success rate inferred from a sample of patients be easily interpreted by and applicable to individual patients?

This is not an insurmountable problem. Each clinic has access to the treatment data routinely collected by the clinic. Such data can be used to form estimations of personalised success rates of IVF treatment. Example 1 in Appendix 2 illustrates in greater detail how this could be done based on an established statistical model adopted by NHS England for a different purpose (which is to compare risk-adjusted hospital-level mortality rates). I illustrate in the example how the relevant statistical model can be used to estimate with a certain degree of precision the expected rate of success of a given patient with certain characteristics, which can then be compared with the observed rate of success in the clinic for such patients.

Whatever quality measures are used, they are unlikely to be perfect. In the fertility sector, reported evidence depends on the characteristics of the patients (such as underlying causes of infertility, any pre-existing conditions, and age, etc.), as well as the performance of the clinic. Clinics can improve performance rating by strategically selling to the ‘right’ patients and refusing complex cases. Such adverse incentives are highlighted by Dranove et al. [45] in the empirical case of mandated ‘cardiac surgery report cards’ in the US. This stresses the importance of reporting the success rate adjusted for patient mix of a given clinic as a measure to help patients effectively review and verify clinics’ performance. Example 2 in Appendix 2 illustrates in further detail how this could be achieved based on NHS’s established practice of comparing and reporting risk-adjusted mortality rates (for different diagnoses) across hospitals.

To increase the reliability of the evidence disclosed by clinics, it is important that such evidence is verifiable, at least to some extent. Buyers’ willingness to pay is influenced not only by the availability of the evidence but also by their perceived reliability of the available evidence. Even though value judgement is ultimately unavoidable when determining the reliability of evidence, in practice, developing standards/practical guidelines to assist with the assessment of reliability of available evidenceFootnote 8 could allow less distorted elicitation of values and preferences about management options presented to the end users. Example 3 in Appendix 2 illustrates how data and methods for producing the evidence could be assessed in the case of IVF success rates to ensure the reliability of evidence to some extent.

Mandatory disclosure may fail to achieve any desired impact on treatment quality if a large number of patients decide not to engage with the disclosed evidence. In the UK fertility sector, for instance, HFEA survey evidence (see Table 3 in Appendix 1) indicates that patients make use of online information when searching for clinics and would like to be more engaged with clinics to improve treatment outcome.

Mandatory quality disclosure could lower the barriers to patients’ pre-purchase search for clinics. The regulator could also play a more prominent role to encourage patients to review their experiences and advertise such an information-sharing platform to the public. Such platforms can also be used to facilitate independent quality (especially in relation to treatment effectiveness and safety) review based on patients’ feedback. This will help patients to increase their chances of selecting good-quality clinics. Example 3 in Appendix 2 further illustrates this point. Unfortunately, not many patients in the selected sample documented by the CMA [27] and HFEA [28] (see Tables 2 and 3 in Appendix 1) are aware of the existing HFEA webpage that allows patients to review their experiences, provide ratings, and access success rates (but not personalised, or adjusted for patient mix) across clinics.

Since the quality of treatments is not only reflected in the dimension of effectiveness but also in the dimension of safety, mandatory disclosure may harm patients if clinics only focus on boosting the reported success rate at the expense of unreported long-term safety. This explains why regulators play a very important role in verifying the long-term safety of treatments and drugs. For instance, the sector regulator could prioritise resources to commission independent research into the understanding of the long-term risk of the commonly used fertility drugs/treatments facing both patients and children conceived as a result of the relevant IVF treatments by doing long-term follow-up studies with IVF patients/children.

Given the challenges mentioned above in implementing mandatory disclosure, a point worth discussing is whether there might be better alternatives. There are other possible institutional solutions discussed in the literature, especially relating to treatment and diagnosis markets (see a review by Balafoutas et al. [13]). One potential remedy extensively discussed is the use of liability clauses (by e.g. Fong et al. [48] and Dulleck et al. [49]) to mitigate the issue of underprovision of quality (and other adverse incentives mentioned in Sect. 2). Whereas it is in theory a potentially powerful mechanism, the implementation of liability rules in practice requires that the success of a service is not only observable by the patient but also verifiable. In many cases, the success of services cannot be easily observed or verified. For instance, in the IVF sector, success is in part random. Thus, a failing treatment is no perfect signal of undertreatment. The effectiveness of liability clauses therefore necessarily requires the disclosure of reliable evidence relating to treatment effectiveness and safety.

Even though liability clauses may be difficult to implement without quality disclosure, some studies dating back to 1963 (Arrow [9]) discuss the implications of the possibility that physicians have ethical obligations for the patients’ welfare. If so, one should expect such ethical concerns to reduce the adverse effects on treatment quality arising from the informational asymmetry between patients and physicians.

There is some evidence from experiment laboratories to indicate that financial incentives are not the only motivating factor for physicians who may exhibit some degree of altruism and concerns for patients’ needs (see, for example, evidence provided by Hennig-Schmidt et al. [50] and Hennig-Schmidt and Wiesen [51]) and that experts who have made a non-binding promise to a consumer are indeed less likely to engage in fraud [52]. However, given that the degree of ethical concerns for patients may well differ from one physician to another (see, for example, evidence provided by Godager and Wiesen [53]),Footnote 9 the overall impact on seller behaviour remains unclear.Footnote 10 In addition, the above observations in the IVF sector suggest that clinics as a collective organisation, as well as individual physicians, may not always have compatible incentives. For instance, IVF patients have a tendency to avoid regret and are therefore likely to be less sceptical about the effectiveness of add-on treatments (see patient quotes in Fig. 3 in Appendix 1). As a result, clinics as an institution may have little incentives to invest in diagnosis efforts to better understand (and ultimately improve) the effectiveness and safety of treatments. In this case, even though individual physicians (facing a lack of available evidence) may have ethical concerns for patient welfare, what they can do individually to improve the quality of care for patients is likely to be limited.

6 Conclusions

Using the UK IVF sector as a case study, and based on economic evidence, I illustrate, that inadequate quality provision in terms of treatment effectiveness and safety can be associated with a lack of reliable evidence. To address the issue of suboptimal quality associated with clinics failing to disclose reliable evidence fully and voluntarily, I then assess the rationale for possible legislative intervention of mandating evidence disclosure. The discussion of mandatory evidence disclosure is extended to demonstrate that care must be taken when designing such measures to avoid adverse incentives.

The discussions above do not go much beyond the economic principles that could be applied to the understanding and design of mandatory quality disclosure, and the illustrative examples in Appendix 2 cannot fully capture adverse incentives associated with misrepresentation of evidence in all cases or segments of the healthcare sector. Similarly any general framework/standards to assess the reliability of evidence are unlikely to completely capture the misrepresentation of evidence in all cases.

However there are reasons to be optimistic. Our observations in the context of the IVF sector in the UK point to the important potential for patients to improve quality provision. Thanks to the rapid development of information technology, patients have better access to online information than ever. Patients also have means to share experiences and learn about the service provision of different clinics using online platforms or social media. Therefore, there is still plenty of room to further engage patients with clinics’ service provision and evidence disclosure. Therefore, in my opinion, patients’ role in evidence disclosure, assessment and verification, with the purpose to improve healthcare quality in the context of information asymmetry, is to be better understood and more fully explored in the new digital era.

It is important to note that the conclusions drawn from this study should be applied with caution to other segments within the healthcare sector. For instance, other areas of the healthcare sector may be characterised by patients who are more (or less) engaged/responsive to reliable evidence. The nature of the treatment may also determine how straightforward it is to construct objective measures of treatment effectiveness and safety. In publicly funded healthcare sectors, the provision of treatment quality depends in part on the government’s willingness to pay, which is influenced by various government budget constraints and other factors which are not considered in this study.