Intended for healthcare professionals


Use of adherence monitoring in drug contracts tied to outcomes: put patients first

BMJ 2022; 376 doi: (Published 07 March 2022) Cite this as: BMJ 2022;376:e062188
  1. Theodore Bartholomew, GP specialty registrar1,
  2. Huseyin Naci, associate professor2,
  3. Emma Robertson, patient advocate3,
  4. Harald Schmidt, assistant professor4
  1. 1Royal Surrey County Hospital NHS Foundation Trust, Guildford, UK
  2. 2Department of Health Policy, London School of Economics, UK
  3. 3London, UK
  4. 4Department of Medical Ethics and Health Policy, University of Pennsylvania, USA
  1. Correspondence to: T Bartholomew tb.public{at}

Theodore Bartholomew and colleagues examine how contracts linking drug payments to effectiveness may affect patient trust and autonomy

Healthcare payers, including NHS England,1 are making increasing use of outcomes based contracts for new drugs.12 Under these contracts payment for drugs is tied to real world effectiveness instead of a fixed price per unit.3 A typical agreement might entail a manufacturer either wholly or partially refunding drug costs if the agreed outcome threshold (cure, reduction in mortality, biochemical outcome) is not met. Although these contracts can facilitate access to new drugs when cost effectiveness is unclear, they present challenges with measuring outcomes and have potential for political and commercial conflict of interests.345

Patients’ adherence to drugs attains new importance in outcomes based contracts. Manufacturers may argue that suboptimal adherence is responsible for a poor outcome rather than ineffectiveness whereas payers may argue the opposite. Medication non-adherence is widespread with rates of up to 50% reported in hypertension, diabetes, asthma and cancer, and the reasons for it are complex and poorly understood.678 One way to help assess whether outcomes reflect effectiveness is to include a requirement for adherence monitoring in outcomes based contracts. This has clear measurement advantages for both manufacturer and payer, but whether it is in the interests of patients is unclear. We consider how outcomes based contracts and adherence monitoring might affect patients within a nationalised health system such as the NHS.

Use of outcomes based contracts

The confidential manner in which drug contracts are negotiated9 has obscured the emergence of outcomes based contracts globally. The first publicly disclosed contracts were in the US in the mid-1990s.2 In one example, Merck refunded up to six months of prescription costs (to both patient and payer) if simvastatin plus diet did not lower cholesterol to target levels.5 In England, North Staffordshire Health Authority agreed a similar contract with Parke-Davis (Pfizer) in 2000.10

The first national outcomes based contract in the UK was for four multiple sclerosis drugs. Patients were monitored using a clinical disability score and the price was adjusted to achieve a cost per quality adjusted life year (QALY) of £36 000 or less, effectively leveraging the contracts to close data gaps.11 More recently, NHS England has implemented a “pay per cure” contract for drugs to treat hepatitis C in which the manufacturer is paid only if the patient has a sustained viral response (table 1).13 NHS England has stated that a “series” of outcomes based contracts have been agreed in recent years, although few have been publicly disclosed.1 Greater Manchester Health and Social Care Partnership has also said it intends to introduce them for cancer drugs when the NHS and manufacturers struggle to agree a price.14 Use of outcomes based contracts across Europe and the US is expected to increase as the contracts have potential benefits for both payers and drug companies.215

Table 1

Examples of outcomes based contracts in the UK

View this table:

Payers such as NHS England are primarily interested in using outcomes based contracts to more tightly control a drug’s costs relative to its outcomes, and to provide access to expensive drugs when there is uncertainty about effectiveness and affordability.914 In theory, the contracts allow additional outcomes data to be gathered so that the drug can be priced according to its real world value.14

For manufacturers, one attraction of these contracts is that they can help show their product’s effectiveness over competitors.9 There are concerns, however, about being held accountable for outcomes given manufacturers lack of control over how a medication is prescribed or taken.9 In one publicly disclosed US contract, a payer was given additional discounts if administrative data showed that diabetes patients had been adherent, although specific stipulations were not disclosed.3 As contracts are usually confidential, it is difficult to determine how often adherence is tied to payment, but this is unlikely to be the only example.

Adherence monitoring

Adherence has previously been defined as “the extent to which patients take medications as prescribed.”16 Newer conceptualisations of adherence, however, recognise its complexity by appreciating the need to consider both multilevel (regimen, patient, provider, health system) and multidimensional (initiation, implementation, and persistence) factors.71617 There is no single ideal measure of adherence, and no universally accepted threshold for defining adherence.1618 However, it is important to capture subjective measures (those that evaluate a patient’s beliefs and explanations) alongside objective measures (those that capture a record of medication use) in any assessment.18

Health systems routinely record many metrics (eg, blood pressure, obesity),19 yet adherence is not recorded and may only be informally checked by clinicians. Recently, multiple technologies have emerged that monitor adherence remotely (box 1).20 Evidence on the acceptability of adherence monitoring technologies and their ability to improve patient outcomes is typically poor.2122232425 The effectiveness of different methods to improve adherence varies and depends on disease area studied and the resources allocated.2122232425 Although their utility and cost effectiveness remain unclear, these technologies are of particular relevance to outcomes based contracts.2627 Remote monitoring may provide greater accuracy than, for example, pharmacy dispensing reports, which the NHS currently uses to monitor treatment completion in patients with hepatitis C.28

Box 1

Remote adherence monitoring technologies

Text messages/electronic diary

  • Provider prompts patient by text message or electronic diary

  • Patient reports adherence by text message or electronic diary

Signalling bottle

  • Pill bottle flashes light when pill should be taken

  • Pill bottle automatically sends a message to a computer/smartphone each time the cap is removed

  • Computer or smartphone records whether or when pill bottle was opened

Video check (with healthcare professional)

  • Professional observes patient taking pill using video platform

  • Professional records whether or when pill was taken

Video check (automated)

  • App with facial and pill recognition capability analyses patient through smartphone camera

  • App records whether or when pill was taken

Signalling pill

  • Sensor is embedded within a pill

  • Smartphone app reminds patient when pill should be taken

  • When pill reaches stomach, signal is sent to a receiver which relays information to a smartphone recording when pill was taken

Measurement of physiological or biochemical marker

  • Measurement of physiological markers (eg, heart rate or blood pressure)

  • Measurement of biochemical markers (eg, blood glucose monitoring)


Implications for patients

Patients have a clear interest in their health. Whether a patient wishes or is able to be adherent depends on numerous complex factors, many of which are grounded in the relationships they have built with their medical teams and the communication between those teams.717 Patients, however, often cite forgetfulness as a factor, and find adherence more challenging the more frequently a medication has to be taken.726 Typically, adherence is high for patients with acute conditions but drops steeply for chronic conditions after six months of treatment.26 Consequently, if patients choose to use adherence monitoring as part of a shared decision making process, it may support them to act autonomously.29 Conversely, monitoring (particularly objective monitoring alone, which simplistically measures adherence as a number without understanding the barriers a patient may face to being adherent) may increase responsibility on patients in ways that offer no or marginal additional benefit and undermine, rather than support, their interests.

Patients have many reasons for not taking their medications.717 Side effects, for example, are a major predictor of non-adherence because they reduce quality of life.26 Adherence may also depend on the drug’s perceived benefit. While adherence monitoring may help improve clinicians’ understanding of side effects,30 patients may feel uncomfortable if monitoring causes them to be labelled in an unqualified manner as “non-adherent.”

Concerns also exist about whether adherence monitoring may unduly restrict patient liberty and autonomy.2931 Expectations to use adherence monitoring could undermine voluntariness or even become coercive if, for example, a patient is concerned that non-use will harm the relationship with their physician. Another concern stems from tying financial rewards or penalties to adherence. The NHS does not presently allow financial penalties, but incentives have been trialled, for example, in smoking cessation and weight loss programmes.3233 Providing financial incentives to patients could compromise consent, particularly for patients from marginalised groups for which incentives could have disproportionate leverage.34 Others may have concerns that their confidential information might be sold to third parties and potentially linked back to them.30 Further testing in clinical practice is required to understand fully the acceptability of adherence monitoring, but patients have already raised concerns about how it may affect face-to-face contact time, confidentiality, and difficulties using the technologies.3536

Societal perspective can influence personal responsibility

An important consideration from the societal perspective is the patient’s moral (and in some cases, legal37) obligations to consider how non-adherence may affect the health of others. Public health risk, for example, is the justification for using directly observed therapy in some patients with tuberculosis.37 The international response to the covid-19 pandemic shows that public health can motivate obligations that go far beyond the individual.38 In principle, the case for using adherence monitoring on public interest grounds strengthens as risk of harm to others increases. Yet, it also increases healthcare professionals’ obligations to communicate with patients about the reasons why adherence may be important, which is difficult to do properly with limited consultation time.

Within a nationalised health system such as the NHS, there is a societal expectation that the public should use collective resources responsibly, such as by keeping their appointments.3940 In England, these responsibilities are set out in the NHS Constitution, which states: “Please follow the course of treatment which you have agreed, and talk to your clinician if you find this difficult.”39 Yet, this appeal also extends the other way, leading citizens to hold expectations about their treatment and how, for example, their data should not be used for profit. Societal expectation could extend to medication non-adherence, given its opportunity cost (health gains forgone) is estimated to be more than £500m annually in the UK.41 This, however, must be considered carefully alongside the wide ranging and legitimate reasons that patients may have for not taking their medications.717

Risks to patient-provider relationship and health system

Critically, adherence monitoring seems likely to affect one of the fundamental tenets of healthcare: the patient-provider relationship. The interactions between professionals and patients are already highly variable, and trust can be eroded if medications do not have desired consequences, if professionals fail to communicate effectively, and if the patients have concerns about being taken advantage of.42

Combining outcomes based contracts with adherence monitoring is likely to have unpredictable consequences. Physicians, for example, may exert implicit or explicit pressure on patients to use adherence monitoring to gain insights into how they take their medications. Behaviours may also be influenced by the amount of public information available for each contract, including knowledge of the potential financial implications of non-adherence. Both the UK National Institute for Health and Care Excellence (NICE) and the Association of the British Pharmaceutical Industry (ABPI) acknowledge that all relevant information about drugs being appraised should be put in the public domain.43 However, clinical and economic data of importance to patients, clinicians, and researchers are often redacted.44 Contractual stipulations relating to adherence monitoring and the effect of non-adherence on reimbursement are of direct relevance to patients, the public, and health system and should therefore be in the public domain.

Patient centred approach

Use of outcomes based contracts is likely to continue to increase, driven by the commercial interests of manufacturers and the economic interests of payers to limit the budgetary impact of high cost drugs. Patients, society, and health providers—particularly in a nationalised system using collective resources such as the NHS—have a right to greater involvement in how these contracts develop and are negotiated. This process should begin with the creation of a new transparency agreement between ABPI and NICE that is co-developed with patients. Additionally, we echo calls for the regulation of data transparency in drug appraisals.44

The importance of using both subjective and objective adherence monitoring must be recognised, as well as a more nuanced appreciation of the multilevel and multidimensional nature of non-adherence. The effect on patients who are reluctant to use adherence monitoring must also be considered.

The effects on behaviour and patient-provider relationships are likely to vary considerably according to disease characteristics, patient population, and the transparency with which contracts have been negotiated. Patient and public expectations will also be different across nationalised, privatised, and insurance based health systems, and will vary according to cultural and societal contexts.

Wider debate and more qualitative research needs to be undertaken with patients, healthcare professionals, and policy makers on outcomes based contracts and adherence monitoring to understand acceptability and feasibility. Both adherence monitoring technologies and the contracts they are meant to support will fail if they are not created in partnership with patients and with patient centredness as the overarching goal.

Key messages

  • Outcomes based contracts seek to align payments for drugs with their real world outcomes and are gaining traction worldwide, including in the UK

  • The contracts raise novel issues for patients as medication adherence may affect the revenues of manufacturers and costs to the health system

  • Adherence is a complex issue, and monitoring technologies may exacerbate tensions created by the contracts between patients and financial outcomes

  • Patient centredness and transparency must be prioritised in the development of contracts and any use of adherence monitoring technologies


  • Contributors and sources: TB has a special interest in medical ethics and health policy. HN conducts research and teaches on pharmaceutical policy and has written extensively on pharmaceutical economics, policy, and regulation. ER is a metastatic breast cancer patient and campaigner who has worked on patient and public involvement work with Cancer Research UK, the Professional Record Standards Body, and Imperial Cancer Research. She is a trustee for the grassroots cancer charity Mission Remission. HS’s research focuses on reducing disadvantage and improving opportunity for vulnerable populations in health promotion and priority setting. The idea for the article was conceived by HS. TB wrote the first draft and led all subsequent revisions. TB, HN, and HS contributed to all subsequent drafts. ER contributed to later drafts, providing critical patient perspective. All have read and agreed to the final version. TB is the guarantor.

  • Competing interests: We have read and understood BMJ policy on declaration of interests and have no interests to declare.

  • Provenance and peer review: Not commissioned; externally peer reviewed.