House of Commons - National Health Screening - Science and Technology Committee

National Health Screening - Science and Technology Committee Contents

4 Communicating the risks and benefits of health screening

49. As Chapter 1 highlighted, screening—like any clinical intervention—has the potential to do harm as well as good. Exploring how effectively the possible risks and benefits of screening are communicated to, and understood by, the public formed a substantial part of this inquiry. Professor David Walker, Chair, UK National Screening Committee (UK NSC), identified "two big" communication "problems": "one is what information we should be trying to pass on and what the messages are that we need to be giving. Secondly, how good are the processes for transmitting that information?"[134] This chapter examines the content of the message and its delivery. Particular consideration is given to where responsibility for communication lies and whether consistent communication across programmes is possible.

Public perceptions

50. Witnesses repeatedly told us that the overall public perception of screening was positive. In the case of cancer screening programmes, Professor Jane Wardle, Academy of Medical Sciences, suggested that "enthusiasm" for the programmes arose, "at least partly," because they signalled that "something is being done […] to help".[135] According to Public Health England, the generally positive attitude towards screening can make it a "challenge" to explain to the public "that there is a balance of risk and benefit".[136] Public Health Wales stated it had "found a resistance amongst [the public] to information regarding risks of screening"[137] adding that, in its opinion, the risks and benefits of screening remain "poorly understood by both professionals and the public, with benefits typically being over-estimated, and risks under-estimated".[138] Other witnesses indicated that such positive perceptions of screening led to high, and perhaps unrealistic, expectations. According to Síle Lane, Sense about Science, the "expectations people have about screening are not matched by what screening programmes can deliver".[139]

Delivering information

51. There was some suggestion that, in the past, clinicians may have actively avoided publicly discussing, and documenting in public information materials, the possible risks of screening. Recounting his time as "a director of public health in a primary care trust", Dr John Middleton, UK Faculty of Public Health, identified "the complicit idea", which he and "many" of his "colleagues may have had", that "if you tell people the whole truth, getting them into the screening programme will somehow be jeopardised".[140] He added that providing people with a "much more sophisticated, honest and open set of information" was necessary in order "to enable them to make informed choices".[141] The concept of "informed choice" was highlighted throughout the inquiry as the goal which information on screening should strive to achieve. Rather than encourage a "blanket promotion"[142] of screening, witnesses explained that informed choice materials were designed to provide potential participants with "clear, unbiased information"[143] to enable them to "assess the offer of screening"[144] and decide "whether to accept or decline" it.[145] Recognising that choices may be influenced by personal circumstances and values, and that "some people will choose one particular set of risks compared with another", Public Health England noted that informed choice materials should also make "it clear that not taking it [the screening test] may be a reasonable choice".[146]

52. Information on the risks and benefits of taking part in a screening programme is provided to potential participants via a number of routes and media. The method of delivery, and its timing, appears to be largely dependent on the programme in question and its point of engagement with the individual. As the Minister explained:

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In the case of bringing people into the health service for cancer screening, written evidence indicated a reliance on enclosing information materials, particularly leaflets, with the letter inviting the individual to attend.[148] In the case of newborn screening, by contrast, we received evidence that engagement with parents began during the antenatal period.[149] For example, Robert Meadowcroft, Muscular Dystrophy Campaign, told the Committee that there was "no reason why one would not start a dialogue at [the first antenatal visit] to make sure there is ongoing discussion about newborn screening and what it might mean for the parent".[150] However, he added that, in the case of Duchenne muscular dystrophy, 82% of parents surveyed:

151

53. Enabling informed choice is not a new approach. As early as 2000, the UK NSC stated that it had:

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Item 20 of the UK NSC criteria for appraising the viability, effectiveness and appropriateness of a screening programme also states that "evidence-based information, explaining the consequences of testing, investigation and treatment, should be made available to potential participants to assist them in making an informed choice".[153] We were not, however, provided with a clear definition of "informed choice" or what it means to be "informed". When asked how the Government defined informed choice, and how it measured if someone was informed enough to make a choice about screening, the Minister responded that it was "a challenge".[154] Without a clear definition, or metrics, it will be difficult to know if people are making informed choices. The Academy of Medical Sciences noted that the UK NSC "does not provide information on […] rates of informed choice for those offered the programmes they manage and there does not seem to be a systematic review of the topic available in the scientific literature".[155]

54. We support the principle of enabling informed choices to be made about participation in a screening programme. However, we are struck by the lack of clarity over what is meant by "informed choice", how it should be measured and the corresponding dearth of information on whether it is being achieved in practice. We recommend that a definition of "informed choice" is agreed by the UK National Screening Committee, in conjunction with its stakeholders, as soon as possible. The definition should have regard to the legal rights set out in the NHS Constitution, particularly those rights that make reference to consent and informed choice. We also recommend that this definition is subsequently used as a starting point to evaluate, and compare across screening programmes, whether individuals are being supported to make an informed choice about participating.

Designing and producing information

55. Communications about screening for breast cancer have recently been overhauled. Jessica Kirby, Cancer Research UK, identified the revised leaflet on breast cancer screening as "probably the first example within the national screening programme of a piece of information material that is explicitly on informed choice".[156] Several witnesses told us that they had been members of the "expert panel" that was involved in producing those "new resources" on breast cancer screening.[157] Capturing the full range of benefits and harms, and presenting them in a concise, accessible fashion was identified by witnesses as a one of the key challenges facing the panel. Professor Jane Wardle, Academy of Medical Sciences, described "a constant trade?off between giving people so much material that they would be overwhelmed by it and including all the caveats and information you wanted".[158] Professor David Walker, Chair, UK NSC, agreed, adding:

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Explaining over-diagnosis was identified by Professor Wardle as particularly demanding. Recounting her experience of focus group work, she stated that the public "find it extraordinarily difficult to understand both how there could be a cancer that might not have done you harm, and how it could possibly be that, if there is such a thing, we do not already know".[160]

56. Noting that the leaflet development process "involved a citizens jury of women, […] a public consultation with over 1,000 people and 50 professional groups", Professor Walker was of the view that continually "involving all of our stakeholders, particularly […] the people who are going to be using the services" was essential in order to make the leaflet "as good as we can".[161] Witnesses concurred that public and patient involvement in the production of all screening information materials was vital. Speaking in the context of newborn screening, Robert Meadowcroft, Muscular Dystrophy Campaign, suggested that patient groups "would have credibility in adding to information and making sure the language was accessible".[162]

57. Citing "early anecdotal" feedback, Cancer Research UK reported that the new information materials on breast cancer were "helping women appreciate the existence of benefits and risks" but raised concerns that there were "no public plans for the update or review of the […] materials over time".[163] Others disagreed that the new leaflet represented an improvement. Dr Margaret McCartney stated that the leaflet "still does not fully explain the hazards of false positive diagnosis, i.e. mastectomy and radiotherapy being given unnecessarily"[164] while Professor Susan Bewley, King's College, London, commented that the "risks [of breast cancer screening] are not being communicated fairly".[165]

58. Our attention was also drawn to inconsistencies in the content and production of information materials, both within and across programmes. Sense About Science noted that NHS patient information on breast cancer screening for "those over the age of 70 […] does not mention risks, false positives/negatives or overdiagnosis".[166] Cancer Research UK suggested that "the overall positioning of NHS communications about screening [appeared] somewhat disjointed and inconsistent", since the principles guiding the production of the breast cancer screening leaflet for the 50-70 age group had "not been applied to the information about all screening programmes, in all UK nations".[167]

59. Submissions to the inquiry also highlighted that the information needs of screening programme participants varied. The Academy of Medical Sciences noted that "some patients want simple messages, while others seek more comprehensive information" and questioned whether "routinely provided information" was "adequately meeting the needs of the less advantaged".[168] Delivering "meaningful information […] to groups with low levels of health literacy" was cited by Public Health Wales as posing a particular challenge, while the Royal National Institute of Blind People (RNIB) stated that "health information is not usually provided to blind and partially sighted people in a format that they can access".[169] To cater for different information requirements, Cancer Research UK suggested providing information "at a number of levels of detail", such as "a brief overview with options to move on to more in-depth explanations".[170]

60. Dr Anne Mackie, Director of Programmes, UK NSC, told us that "almost all of the leaflets" were "being updated in one way or another", though it was not clear if the updates were following the same process used to revise the breast cancer screening leaflet.[171] When asked if a set of best practice guidelines was being developed to direct the production of consistent materials across all screening programmes, Professor David Walker, Chair, UK NSC, replied that "it is done in each individual programme. We do not necessarily do that at a national level over all the programmes".[172] The Minister added that she did "not see" what independent oversight across all the programmes "would bring" but stated that she was "open-minded about looking at it".[173]

61. Although there are differences between the screening programmes, we are concerned about inconsistencies in the method of developing public information, both within and across programmes. Producing accurate, concise and accessible public information on screening will always be challenging. However, we were surprised that there was no mechanism to share best practice across all programmes and that there was no UK-wide oversight of all NHS screening information materials.

62. We encourage the UK National Screening Committee and NHS to develop, pilot and evaluate approaches to providing screening information that can be accessed at the level of detail desired by individual patients and practitioners.

63. To avoid inconsistencies in the information provided across programmes, we recommend that the UK National Screening Committee devises and implements a standard process, underpinned by a publicly available set of criteria, for producing information that facilitates an informed choice to be made about participating in a screening programme. The production process should consult with a wide range of stakeholders and should subject information materials to extensive user testing, both before and after implementation. Information materials for all NHS screening programmes should subsequently be revised according to the process and be reviewed at regular intervals.

EXPRESSING THE OUTCOMES OF SCREENING: SCREENING STATISTICS

64. The statistics used to express the outcomes of screening to the public were a source of confusion and disagreement among witnesses. Concerns focused on the uncertainty surrounding the numbers needed to treat (NNT) to save a life from screening and the risk of "over-diagnosis". Evidence relating to these concerns was put to us primarily in the context of screening for breast cancer. Professor Michael Baum, Advocates for Honesty and Transparency in Breast Screening, told us that the most recent leaflet on breast cancer screening claimed that "screening saves about 1 life from breast cancer for every 200 women who are screened. This adds up to 1,300 lives saved".[174] Professor Baum stated that this figure was "based on mathematical models that are simply not true".[175] Dr John Middleton, UK Faculty of Public Health, noted that he had seen "only 84" as the NNT to save one life "in an American journal".[176] HealthWatch cited different figures from the "Cochrane Library website"[177] while Breakthrough Breast Cancer highlighted the Independent UK Panel on Breast Cancer Screening ("the Panel") and its 2012 review of the Benefits and Harms of Breast Cancer Screening which, it stated, "was established to evaluate the available evidence" and provide "an up-to-date estimate of the likely benefits and risks associated with routine screening".[178]

65. According to the Panel, variation between estimates arises from "the age of women screened and the durations of screening and follow-up".[179] The Panel also noted that differing views of the evidence had arisen, in part, "from disagreements over the validity and applicability of the available randomised controlled trials of breast screening, and from questions about the usefulness and interpretation of observational data on breast cancer incidence and mortality".[180] The Panel assessed that 1 breast cancer death is "averted for every 235 women invited to screening for 20 years" and that, in the UK, "inviting women aged 50-70 every three years, prevents about 1300 breast cancer deaths a year".[181]

66. Concerns about the risk of "over-diagnosis", namely "the diagnosis of […] cancers by the screening programme which wouldn't have been detected otherwise, but which would have grown so slowly they would never caused problems during a woman's life",[182] were also highlighted to us.[183] Professor Baum stated that "the estimate is that for every one breast cancer death avoided either three or, as the upper limit, nine women are over-diagnosed and over-treated".[184] The Panel reported that there were diverging views "on how to estimate the amount of overdiagnosis" resulting in "estimates of the frequency of overdiagnosis [varying] widely, from approximately 0% to 50%".[185] Prefacing its calculation with the statement that "there are no data to answer this question directly", the Panel provisionally estimated that the "frequency of overdiagnosis was of the order of 11% from a population perspective, and about 19% from the perspective of a woman invited to screening".[186]

67. When asked how the UK NSC handled uncertainty in the breast cancer screening figures, Dr Anne Mackie, Director of Programmes, UK NSC, replied that "we do our very best to try and get an answer".[187] She went on to note that the UK NSC "cannot do a randomised control trial and say, 'Let's leave these women and see what happens, and let's treat these'" and therefore it has "to make assumptions […] about how many women we are helping and harming".[188] Dr Mackie added that it was necessary "to be open" with the public and say "'our best estimate is 1,300 lives that we save' [...] but we have to be honest and say that it might be a bit more or a bit less".[189] After hearing witnesses' concerns about the uncertainty relating to the numbers needed to treat and the risk of over-diagnosis, the Committee put it to Professor David Walker, Chair, UK NSC, that the statistics should be reviewed by the UK Statistics Authority. Professor Walker stated that he "would have no objection" to this but added that he did "not think it [was] a necessary step".[190]

68. Pointing to the "poor" level of "statistical comprehension of the majority of the UK population",[191] other witnesses suggested using different "techniques to aid understanding" in information materials including "minimising the amount of numerical information" and relying more on "clear graphical or visual representations" (also referred to as "infographic methods"[192]) and "natural frequencies rather than percentages or fractions".[193]

69. In the context of breast cancer screening, we have no reason to doubt the detailed work undertaken by the Independent UK Panel on Breast Cancer Screening in 2012. Its report clearly highlights the assumptions made by the Panel when analysing the data, as well as where uncertainties lie in its estimates of benefits and harms. It is, however, vital that any uncertainties are also acknowledged in screening information materials and expressed in a clear, accessible way. We consider that the UK Statistics Authority and its executive office, the Office for National Statistics, have a valuable role to play in ensuring the veracity of the statistics used in screening information materials and the models they are based upon. As the independent body with the statutory objective to promote and safeguard the production of official statistics that serve the public good, we recommend that the Office for National Statistics review and validate the statistics presented in NHS screening information materials.

Training health professionals

70. Health professionals were highlighted at the beginning of Chapter 4 as an important route via which members of the public may access information on the benefits and harms of screening. The opportunity for individuals to discuss screening with their General Practitioner (GP) appeared to vary according to the programme in question. Dr Margaret McCartney, a GP from Glasgow, stated that she did "not get a chance"[194] to discuss with her eligible patients whether they wished to participate in the breast cancer screening programme because the invitation to attend come from a "centralised organisation"[195] and not the patient's GP. Other witnesses suggested that GPs were not taking the opportunity to instigate discussions. Citing results from a 2014 survey of 500 GPs, the Prostate Cancer Advisory Group reported that while men over the age of 50 are entitled to a PSA (Prostate-specific antigen) test free of charge on the NHS, provided they have first had a discussion about the pros and cons with their GP, "fewer than 1 in 10 GPs proactively initiate a discussion about prostate health".[196]

71. Other submissions stated that "screening is often poorly understood by […] clinicians"[197] and that health professionals more broadly can "struggle with the terminology and concepts".[198] The Royal College of Midwives pointed to the "rapidity" of developments in the field and noted that it could be "difficult for midwives to […] remain informed and up to date with the evidence".[199] We also heard evidence that the routine nature of screening for many health professionals, combined with the rarity of some of the diseases screened for (particularly in newborns), may negatively influence the way that information is delivered. Robert Meadowcroft, Muscular Dystrophy Campaign, highlighted the cases of families in Wales who had taken part in newborn screening for Duchenne muscular dystrophy and who had been advised by health professionals, "Oh, don't worry; it [the test] always comes back negative".[200] He noted that while the information they were being given was "well intentioned", it was "not helpful" and potentially increased "the sense of devastation" when a test came back positive.[201]

72. However, Professor David Walker, Chair, UK NSC, stated that "an extensive educational programme" was in place that targeted "everybody, from the clinicians who are delivering the programmes, the patients and the public who are going to receive them, and also the commissioners of services". He added: "we have everything from leaflets and videos to e-learning modules—and even university-accredited courses—for these people".[202]

73. Under the NHS Constitution, patients have the right to be given information about the test and treatment options available to them, what they involve, and their risks and benefits. We are concerned that the rarity of some conditions may lead health professionals to downplay the possibility of participants in a screening programme receiving a positive result and that health professionals can struggle with screening terminology and concepts. We recommend that the Government supports the UK National Screening Committee to step up its education programme and ensure that all front-line health care professionals delivering screening programmes receive regular training to refresh their communication skills, as well as their understanding of available screening programmes and their associated benefits and risks.

Private health screening

74. While focusing predominately on NHS screening programmes, we received some evidence during this inquiry—chiefly from Dr Margaret McCartney—relating to programmes offered by private screening providers. Dr McCartney drew attention to what she saw as the low quality of information provided to individuals paying for private screening. Citing a study undertaken for the consumer rights group Which?, Dr McCartney reported that "one out of six or seven companies was prepared to say that their screening tests could do harm when we asked them that specifically on the telephone".[203] She also indicated that private screening companies were making claims in advertising material—such as "we've saved thousands of lives"—which, she told us, they had "no evidence" for since they had "not followed up people in the long term".[204]

75. Síle Lane, Sense About Science, and Dr McCartney, noted that the screening offered by private companies was "not being run and overseen by the National Screening Committee" and that it was indiscriminate; it was "inviting everyone to come along" rather than "inviting specific people in a specific population to come along for a specific test".[205] Dr Anne Mackie, Director of Programmes, UK NSC, confirmed that the UK NSC "does not have oversight" of screening information delivered in private settings and noted that there had been "quite a lot of discussions" about whether this information was "sufficiently balanced".[206] It was not clear, however, who does have oversight of the information materials produced by private screening companies. Dr McCartney told us that she had:

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76. In response to the points made by Dr McCartney, we wrote to private screening companies to offer them a right of reply. The European Scanning Centre concurred with Dr McCartney's concerns about claims made "by certain companies that they have saved lives as a result of the screening procedures", adding that it was "not something that [their] organisation has ever endorsed or used".[208] Life Line Screening stated that it had "reviewed the messaging" in its "promotional literature" and that, in "consultation with the ASA [Advertising Standards Authority]" it had "recently amended a mention in our literature which stated that we 'helped save thousands of lives'".[209] Life Line Screening was clear that private screening was a "matter of personal choice" while the European Scanning Centre suggested that it could be "positive both to the individual and to the NHS purse".[210]

77. The Minister told us that the advertising materials used by private screening providers had not been drawn to her attention "as a major problem" though she recognised it was a point of "ongoing concern".[211] When asked if it would be difficult to require advertising materials to go through a process of independent validation, Professor David Walker, Chair, UK NSC, stated that he did not know, but noted that "the same proposal" was being discussed in the context of e-cigarettes; a point echoed by the Minister.[212]

78. We recommend that the Government clarifies, in its response to this report, where responsibility rests for ensuring that the information materials and advertisements produced by private providers of health screening are held to the same evidential standards as those produced by the NHS and that they enable people to make an informed choice about participating. We also recommend that the bodies regulating the conduct of health professionals, including the General Medical Council and the Nursing and Midwifery Council, review the effectiveness of their processes for ensuring that those operating in the private sector are providing patients with good quality, balanced information.

Innovations in screening

79. Medicine is a constantly evolving field and screening is no exception. We received evidence from a number of academics currently undertaking research to enhance the targeting of screening through improved "risk stratification". The approach rests on the premise that "a population is not totally homogeneous"[213] and that individuals have detectable characteristics associated with an increased chance of experiencing unwanted outcomes.[214] At present, screening programmes recommended by the UK NSC stratify (or target) based on two "detectable characteristics": age and gender. The PHG Foundation, Cambridge Cancer Centre and PROMISE 2016[215] indicated that risk stratification for cancer screening could be enhanced by broadening the detectable characteristics to include genomic information.[216] According to the Cambridge Cancer Centre, "genomic technologies", such as "sequencing", can provide a better understanding of "inherited genetic variants that are associated with susceptibility to cancer" and that modify individual risk.[217] Dr Hilary Burton, PHG Foundation, suggested that by using information about "the most deleterious variants" to target a breast screening programme "the benefit-harm ratio" can be optimised "because you can screen fewer women and detect a similar number of cases".[218] Also referring to the specific example of breast cancer screening, Professor Baum told the Committee that the programme could be improved by "undertaking a risk assessment" rather than "screening everybody" in the 50-70 age group.[219] He added that this would "exclude the very high-risk from screening, because what they need is genetic counselling".[220]

80. The need to consider the non-genetic components of risk—including lifestyle and environmental factors—was also raised by witnesses, particularly in relation to prostate, breast and ovarian cancers. Professor Ian Jacobs, PROMISE 2016, suggested that the "nirvana" he was looking to achieve rested on combining "genetic predisposition, […] demographic and social differences and epidemiological differences, into an algorithm" that accurately defined a women's risk of ovarian cancer.[221] Owen Sharp, Prostate Cancer UK, stated that, "masses of information" was not necessarily needed in the context of prostate cancer to "develop different risk trajectories" for men.[222] Instead, he suggested that putting "pieces of information together", including family history and ethnicity, alongside an assessment of lifestyle, could be used to establish a risk profile alongside screening.[223] Looking further into the future, Professor Ian Cree, Early Cancer Detection Consortium, highlighted the consortium's preliminary work examining whether it was possible "to deliver a series of tests done on one blood sample that allow you to look for multiple cancers".[224] According to Professor Cree, the benefits of such an approach include the ability "to look for rare cancers" that are too uncommon to sustain an individual screening programme, as well as decreasing the risk of over-diagnosis and false positives through having "a single test that has a high sensitivity".[225]

81. In its report Stratified Screening for Cancer, the PHG Foundation anticipated that a risk-stratified screening programme would be more complex to set up and administer than the screening programmes currently offered.[226] To avoid delays, Breakthrough Breast Cancer stated it was "important" to think ahead about the "implementation of increased risk stratification, so that as effective tools become available they can be adopted rapidly".[227] Considering "how emerging trends and developments might potentially affect current policy and practice" is, according to the Government, an integral part of "horizon scanning" and is "already being done in government departments".[228] Our inquiry into Government horizon scanning found it to be a "potentially valuable activity" that could "enhance both short- and long-term decision-making" but we also identified "inconsistencies of practice and performance" across government departments.[229]

82. During this inquiry, we heard that the UK NSC's consideration of emerging trends, and their possible impact on policy and practice, varied across screening programmes. Both Children Living with Inherited Metabolic Diseases (Climb) and the Save Babies Through Screening Foundation identified an apparent lack of forward planning by the UK NSC in the context of newborn screening, with Climb stating that it had "found little evidence" that the UK NSC was "planning for the future".[230] The Prostate Cancer Advisory Group also questioned what processes were "in place to adapt the [current delivery] model" when new risk information became available.[231] Professor Jacobs, PROMISE 2016, was more positive and reported that his team "already have a dialogue" with the UK NSC in advance of trial data being published on ovarian cancer screening.[232] Dr Anne Mackie, Director of Programmes, UK NSC, stated that the Committee was "pretty well" equipped to adapt to changing technologies, as well as genomic information, and pointed to the example of "non-invasive prenatal diagnosis for Down's [Syndrome]".[233]

83. Throughout this inquiry we have heard about the potential benefits, and concerns about the possible harms, arising from participation in a screening programme. The Committee welcomes the current, ongoing research that aims to improve the targeting of screening programmes towards those in higher risk groups. We have previously documented the NHS's resistance to change and therefore consider it imperative that the UK National Screening Committee (UK NSC) and the NHS set out how they will ensure proven developments in screening risk stratification are supported, and where recommended, implemented, as well as how best practice is to be disseminated. We also recommend that the UK NSC is supported by the Department of Health and the Government Office for Science to develop its capacity for "horizon scanning" and to embed it in its operations.

134 Q249 [Professor Walker] Back

135 Q25 [Professor Wardle] Back

136 NHS0040 [Public Health England] para 3.10 Back

137 NHS0048 [Public Health Wales] Back

138 NHS0048 [Public Health Wales] Back

139 Q104 [Síle Lane]; see also NHS0029 [Institute of Biomedical Science] para 3 Back

140 Q98 [Dr Middleton]; see also Q55 [Professor Baum]; Q157 [Dr Burton] Back

141 Q98 [Dr Middleton] Back

142 NHS0049 [UK Faculty of Public Health] para 1.2.7 Back

143 UK National Screening Committee, Annual Report. Screening in England 2011-12, p 10 Back

144 NHS0040 [Public Health England] Appendix 3 para 13 Back

145 NHS0047 [Royal College of Midwives] Back