The Government has issued instructions requiring SBU to carry out a number of specific assignments. We are to evaluate healthcare methods from a medical, economic, social and ethical point of view. Furthermore, SBU is to disseminate its assessments such that care providers can take advantage of its conclusions, as well as monitor use of the knowledge that has been passed on and the results that have been achieved. This report attempts to examine the success of the latter assignment, i.e., to monitor knowledge use and results. SBU is one of the few HTA organisations that have systematically sought to measure the extent to which it has affected clinical practice. We have done so by frequently surveying practice before and after publication of our projects. But assessing the benefits and results generated by an organisation like SBU is not an easy task. Trends are often the product of many interrelated forces. Be that as it may, we hope that this report will prove useful to you.
Måns Rosén Former Executive director SBU
As a national centre of knowledge for the healthcare system, SBU systematically reviews and assesses various preventive, diagnostic, treatment and nursing methods. SBU’s 50 employees collaborate with a network of approximately 1,000 experts throughout Sweden. Both new and established methods are evaluated by systematically reviewing the entire body of scientific literature regarding methods used for treating or diagnosing a disease. Each review is carried out as a project, which may take a number of years to complete if the literature is extensive and many different diseases methods are involved. New methods can often be assessed in approximately six months. Though time-consuming, the systematic approach and active collaboration with experts usually ensure the kind of well-supported conclusions that have the potential to make a significant impact on clinical practice.
SBU has examined a large number of methods and published more than 200 reports. A total of 838 methods were assessed in 2000–2003, of which 121 concerned alcohol and drug dependency. Annual media reports of SBU’s findings have risen from 100 in the mid-1990s to 670 at present. Given Swedish population of 9.4 million inhabitants and circulation figures, more than 2 million newspaper readers are exposed to articles about SBU each month. A series of scientific articles have also been published on the basis of SBU projects. Our reports are respected both nationally and abroad. They are used in the formulation of Medical Products Agency treatment recommendations, National Board of Health and Welfare guidelines, Dental and Pharmaceutical Benefits Agency therapy reviews, and local and regional healthcare programmes.
SBU may be the oldest still existing national health technology assessment (HTA) organisation in the world . Its activities have been subject to a number of external evaluations since 1991 . All of them have been highly favourable. Questionnaire surveys confirm that doctors and other Swedish healthcare professionals have great confidence in SBU. External analysts have concluded that SBU reports are scientifically rigorous in an international comparison. A report at Odense University compared HTA organisations in the Netherlands, Australia, Canada, the UK and Sweden . The report concluded that among selected organisations SBU’s reports were comprehensive and best able to satisfy criteria for clinical, economic, organisational and patient-related relevance.
Given the above accomplishments, SBU is one of the world-leading organisations when it comes to performing systematic reviews of clinical practice. SBU is highly trusted and its reports are considered to be of high quality.
Previous evaluations of SBU have identified a number of factors that highlight its status as an independent and freestanding evidence-based agency. An agency of this type is needed in order to assume primary responsibility for – and possess leading-edge expertise in – the assessment of healthcare methods, to compile reliable data for decision-makers and healthcare providers, to remain unswayed by special interests and preconceptions, and to steer clear of other formal decision-making tasks, such as oversight, prioritisation and administrative measures. Nevertheless, SBU must always be prepared to discuss forms of collaboration and the division of responsibility in order to operate as efficiently as possible.
SBU has no decision-making power and must therefore rely on its trustworthiness and its ability to disseminate knowledge and use effective implementation strategies. In relation to SBUs size we put quite a lot of resources into implementation. SBU uses different means, but the most important one is the involvement of experts in the projects. Actively attending the project meetings over a time period of 2 to 3 years, reading all relevant articles and reaching agreement on findings and conclusions all serve to create effective “advocates” of the results. The medical profession is more likely to change behaviour if theirs colleagues are convinced of the findings. However, SBU uses also many other means to implement its results. These include a thorough identification of stakeholders and target groups for each topic, a widespread dissemination of summaries and summaries targeted for the general public, a well-developed massmedia strategy, arranging and participating in conferences and educational programs, distribution of newsletters, developing special interactive patient cases with medical associations and collaboration with other governmental agencies and the county councils. A successful implementation demands thorough and repeated actions.
Evaluating the benefits and results generated by an evidence-based organisation like SBU is not an easy task. Trends are often the product of many interrelated forces. Generally speaking, SBU has attempted to measure the impact of its reports on clinical practice by conducting surveys before and after the presentation of its conclusions. The impact may not be fully felt for a number of years. But lasting effects emerge year after year, ensuring improved well-being and quality of life, while freeing up resources for more urgent healthcare needs. If we conclude that there is strong scientific evidence for the efficacy and cost-effectiveness of a particular method, we expect that clinical practice will begin to use it more often, budget restrictions permitted. If we determined that the evidence is insufficient, new studies may be required. In any case, routine clinical use of such a method is highly questionable until more conclusive research has been conducted.
We have broken SBU’s reports down into three categories for the sake of evaluating their impact on clinical practice: 1) older reports; 2) reports published in 2006–08, for which some impact should be visible; 3) reports published in 2009, for which the impact may not be fully apparent yet.
The past offer good examples of changes in clinical practice as a response to SBU’s conclusions. Some of them have been documented in various articles [4–7].
An SBU assessment of preoperative procedures found that routine X-ray examinations of the heart and lungs, ECGs or clinical laboratory tests on healthy people without previous relevant diseases do not provide any benefits. The conclusions of the report quickly affected clinical practice, saving the healthcare system approximately 23.5 million euros per year [5, 6] and saving the valuable time of patients.
The use of devices for bone density measurement decreased after SBU found that there was insufficient evidence to recommend either mass or targeted screening .
An SBU report concluded that, generally speaking, there is insufficient scientific evidence for treating women under 80 with calcium and vitamin D to prevent brittleness of the bones . Nevertheless, 79,000 women were given such treatment. A large percentage of the prescriptions were to groups of patients for whom no medical benefits had been demonstrated. That represented a savings potential of 3.1 million euros per year.
SBU’s assessments not only permit resources to be freed up for more urgent healthcare needs, but promote the use of more effective treatment methods. Its reports on depression and the treatment of alcohol and drug dependency have led to a rapid increase in the prescription of the most effective medications in these therapeutic areas. A follow-up of SBU’s projects on tobacco use and oral health concluded that dentists and hygienists had become more insistent in recommending smoking cessation measures after learning about the findings .
When a 2004 SBU report assessed new methods for mass hearing screening of newborns, the national participation rate was approximately 2%. After publication of the report, the rate rose to an estimated 70–75% using the state-of-the-art methods that SBU had recommended. That may have doubled the number of infants who could begin rehabilitation at an early stage. According to the report, the result may improve communication skills and language development. The new technique also ensures fewer false test results.
An SBU report concluded that elderly patients should be prescribed neuroleptics only if they are psychotic – and then in low doses. Neuroleptics have not been shown to be more effective than placebo in the elderly and can cause serious adverse effects. A recently published U.S. study confirmed those findings. The SBU report showed that such medications were still overprescribed. A report by the National Board of Health and Welfare found that the proportion of high-dose prescriptions declined after publication of SBU’s conclusions from 12% in 1999 to 9% in 2001, suggesting greater general awareness of the risks involved . Thus, the SBU project may have helped minimise both suffering and risks.
An SBU report on depression demonstrated that systematic treatment and follow-up allow most patients to fully recover and regain normal function. Among the other conclusions was that drugs and a number of psychotherapeutic methods are equally effective for moderate depression. The report provided data for the National Board of Health and Welfare guidelines and the Pharmaceutical Benefits Board review of antidepressants. It also contributed to a rapid increase in demand for cognitive behavioural therapy by Swedish county councils. Finally, primary care began to use rating scales more than ever before.
In 2002 SBU assessed interventions against obesity and showed that surgical treatment for severely obese patients had clear benefits in health and quality of life for those patients even if the operation carries risks for complications.
After the publication the number of surgical treatments for severe obese patients has increased from 700-800 in 2002 to 8 000 in 2010. According to many experts, the SBU report contributed to this rapid development.
Treatment of mild head injury provides an excellent illustration of SBU’s efforts. A 2000 SBU report concluded that the evidence was insufficient to determine whether in-hospital observation or a new strategy of computer tomography and early return home was more effective. No commercial interests were seeking an answer to the question. A randomised multicentre study launched by SBU and published in 2006 [10–12] showed that the two options were equally effective. But SBU’s updated report found that the new strategy could reduce total costs by one third, thereby freeing up resources for other healthcare needs.
A number of local, regional and national healthcare programmes have been redesigned with respect to procedures for emergency treatment of head injury patients. Since publication of the report, the number of care days for head injury has declined by approximately 6,000 (0.64 per 1 000 inhabitants), releasing approximately 4 million euros to be used for other purposes.
The report found that a combined test of ultrasound nuchal translucency measurement and maternal serum biochemistry (biochemical screening) is the best method for estimating the probability of chromosomal abnormalities. The woman is subsequently offered guidance in deciding whether she wants to take the second step and undergo an invasive test. The approach should reduce the risk of miscarriage.
A review by the weekly journal Dagens Medicin in August 2009 showed that 15 of 21 county councils are offering the combined test to one extent or another. A questionnaire survey found that half of all midwives felt that the information they had previously given to patients was insufficient and that the SBU report had filled that gap.
Among the conclusions of the report were that there was not yet any simple, reliable test for identifying dementia disorders at an early stage and that a combination of consistent blood pressure monitoring of middle-aged patients and healthy lifestyle was key to minimising the risk of developing such a disorder. The report, which was published in three volumes as well as a special version for local authorities, also presented criteria for good nursing practices.
Elderly care, including nursing care for patients with dementia, has become a priority area. The impact of the SBU report is difficult to judge. A project by the Swedish Association of Local Authorities and Regions to improve the training of municipal caregivers has relied heavily on the report. The report has been downloaded more than 180,000 times, an all-time record for SBU.
The report concluded that multimodal rehabilitation facilitates return to work and reduces sick leave. Treatment strategies that include physical activity are also more cost-effective than conventional care alone.
The report served as a basis for the Ministry of Health and Social Affairs rehabilitation guarantee. The findings also provided data for the design of several local and regional healthcare programmes, including those in the Norrbotten and Stockholm regions.
The report found that early development of caries is the single most reliable factor for predicting future caries and that there are effective ways of identifying children and adolescents who are at low risk of developing caries in the next three years.
The National Board of Health and Welfare used the report when drawing up its guidelines.
The report found that a number of methods (counselling, behavioural interventions and school- based measures) of promoting physical activity may be effective. But no long-term follow-ups have been performed.
The National Healthcare Network for Physical Activity on Prescription® has actively disseminated knowledge and the number of prescriptions has risen.
A number of pressure groups wanted the National Board of Health and Welfare and National Food Administration to adopt mandatory fortification of flour to reduce the risk of neural tube defects in newborns. The agencies asked SBU to perform a systematic review of the issue. SBU concluded that fortification reduces the occurrence of neural tube defects. The report identified one problem – studies had shown that folates may play an important role in cell production and could theoretically stimulate the growth of existing tumours. One study had suggested a correlation between high folate levels and colon cancer. If the risk is real, the harms associated with fortification may turn out to considerably outweigh the benefits.
The National Board of Health and Welfare and National Food Administration decided not to adopt mandatory fortification of flour, but rather to provide more information to women of childbearing potential. An additional study has been published supporting the hypothesis that fortification increases the risk of cancer.
In collaboration with other Nordic HTA organisations, SBU published a report on obstructive sleep apnoea syndrome in 2007. The report found that Continuous Positive Airway Pressure (CPAP) is effective in reducing obstructive sleep apnoeas and daytime sleepiness. But there was insufficient scientific evidence to assess the effectiveness of surgery, which is also associated with certain risks.
Prior to the report, Norway used surgery a good deal more often than the other Nordic countries. Following intensive public debate, the frequency of surgical procedures in Norway has declined dramatically. Although Sweden resorts to surgery less frequently, the figure has fallen considerably here as well.
A 2008 Alert report assessed the efficacy of routine childhood vaccination against HPV for the prevention of cervical cancer. The companies that launched the vaccine conducted an intensive public advertising campaign, not to mention extensive lobbying that targeted various groups of decision-makers. The SBU report was one of the few sources that questioned the one-sided and wholly favourable information provided by the manufacturers. The report pointed out that, while promising, the vaccine was effective only against certain viruses (HPV 16 and 18) and did not provide reliable protection against cervical cancer. It will take decades to determine the efficacy of the vaccine against cervical cancer, and its cost-effectiveness cannot be easily evaluated at this point. SBU also discussed the danger that women who had been vaccinated would be less motivated to have Pap smears or protect themselves against other sexually transmitted diseases. The report stressed the importance of a multifaceted assessment of the entire effort to prevent cervical cancer.
The National Board of Health and Welfare used the report as important evidence when making its decision about the use of HPV vaccine. The Board prescribed the adoption of a routine vaccination programme for 12-year-old girls and proposed specific criteria for monitoring it in line with SBU’s conclusions.
The comprehensive review of the literature generated clear evidence for the value of available diagnostic methods and the importance of supervised walking training. But no persuasive evidence was found for a number of medical and alternative methods. The problems associated with assessing surgical procedures were also discussed.
The report has been used for training purposes, for designing healthcare programmes and for LäkeMeDeLsboken, the pharmaceutical handbook of the Medical Products Agency. Because the National Board of Health and Welfare does not issue guidelines in this area, SBU has supported the Swedish Society for Vascular Surgery in designing guidelines based on its report.
The Alert report showed that there is limited scientific evidence that computer-based CBT provides short-term benefits when treating symptoms of panic disorder, social anxiety disorder or depression. The evidence for assessing the effectiveness of computer-based CBT in treating obsessive-compulsive disorder or a combination of anxiety and depression is insufficient.
Since the report was published, the Stockholm County Council has adopted computer-based CBT as a standard option for treatment of anxiety and depression. The National Board of Health and Welfare used the report in developing guidelines for treatment of those disorders.
Proton pump inhibitors relieve the symptoms of undiagnosed gastro-oesophageal reflux more effectively than Histamine type-2 receptor antagonists (H2RA). Eradication of HeLicobacter pyLori is more successful in preventing new gastric ulcer bleeding than prophylactic proton pump inhibitors unless the patient is taking a non-steroidal anti-inflammatory drug (NSAID). Long-term treatment of gastro-oesophageal reflux with proton pump inhibitors is also justified in younger patients, and is just as effective as surgery while causing fewer adverse effects.
The report is among the documents on which the National Board of Health and Welfare is relying as part of its ongoing review of “quality indicators for drug therapy in the elderly” in collaboration with local pharmaceutical committees throughout the country. The report has been cited most often in discussions about treatment of ulcers and gastro-oesophageal reflux disease. The committees have used the conclusions of the report as background descriptions for lists of recommendations and attached them to recommendations for specific medications.
SBU’s survey of clinical practice showed that surgery for gastro-oesophageal reflux was used more often per 100 000 inhabitants in the Stockholm region than the rest of the country. Following publication of the report, the number of operations performed in the region declined by 69% from 2005 (included in the report) through 2008. The frequency of surgery per 100 000 Stockholm inhabitants is now in line with Sweden as a whole.
The report showed that there was insufficient evidence to assess the efficacy of light therapy.
Two regions have completely eliminated light therapy, and one region will monitor results before making a decision. Two clinics in other regions have also stopped using the method.
A key conclusion of the report was that self-management is at least as reliable an option as routine health care for motivated patients who are capable of performing the procedures. The primary benefit of self-management is improved quality of life due to less dependency on the healthcare system. A cost estimate based on Swedish conditions indicates that direct costs for self-management are comparable to, or slighter higher than, routine health care. But if indirect costs associated with loss of production are taken into consideration, self-management can utilise scarce resources more efficiently.
The number of patients trained in self-testing and self-management has increased substantially. According to healthcare professionals who have been involved in this area, both care providers and patients have exhibited greater interest.
The report showed that new testing methods for examining the visual field are effective, that treatment to reduce intraocular pressure delays progression of the disease, and that it is unclear whether either surgery or laser therapy is more effective than drug therapy.
Although the National Board of Health and Welfare does not issue guidelines in this area, the Swedish Ophthalmological Society and Swedish Glaucoma Society are developing practical recommendations and guidelines based on the report and other support by SBU. Work on the recommendations and guidelines is scheduled for completion in spring 2010.
The report concluded that tympanostomy tube insertion for otitis media in children is justified if they have objectively verified hearing loss and reduced quality of life. Theevidence for recurrent acute otitis media is insufficient. Finally, diagnostic methods need improvement.
The Ear, Nose and Throat Association, the Swedish Association of General Practice and the Association of Hearing Therapists have agreed to joint guidelines for tympanostomy tube insertion and amended the quality registry on the basis of the report.
The report concluded that the treatment was effective when administered in monthly injections for up to two years, but that the evidence concerning cost-effectiveness was insufficient.
Clinical practice has trended towards fewer injections without having to sacrifice effectiveness.
The Alert report found that screening was effective and cost-effective in men.
Many regions have started to screen, and expectations are that 90% of all 65-year-old men will have been examined by the end of 2010.
Although the impact of reports published during the year cannot be fully determined, certain effects may be perceptible and some measures may have been adopted.
The report was spurred by a clear trend toward fewer vaccinations throughout the country. Among the reasons were greater concern about adverse effects and the notion that immunity triggered by disease was preferable to vaccine-induced immunity. The report persuasively demonstrated that the benefits of vaccination far exceed potential harms. Nor is there any evidence that measles-mumps-rubella vaccine increases the risk of developing autism.
The report was used by the National Board of Health and Welfare in preparing its informational material about child vaccination and is frequently cited in popular magazines such as Vi föräldrar. Child health centres make widespread use of the report in providing information to uneasy parents. It has aroused great interest internationally, has been sent to the Strategic Advisory Group of Experts on Immunization of the World Health Organization and has appeared in a scientific journal.
The report found that no single measure can resolve all the problems associated with drug therapy for elderly patients. A series of simultaneous changes are needed with respect to information handling, drug distribution and education, as well as prescription and follow-up routines and tools.
A number of initiatives at the national and local level have been partly based on the SBU report. The debate has become more nuanced, and there is a growing realisation that no single measure (such as a review of available medications) can solve all the problems associated with drug consumption by the elderly. Additional combinations of measures are required.
Intensive Glucose-Lowering Therapy in Diabetics
Patient Education in Managing Diabetes
Self-Monitoring of Blood Glucose in Noninsulin Treated Diabetes
2009 SBU reports
While developing its guidelines for diabetes treatment, the National Board of Health and Welfare asked ABU to perform a systematic review of the literature in four particularly thorny areas: intensive glucose-lowering therapy, patient education, self-monitoring of blood glucose, and dietary treatment of diabetes. The first three reports were published in 2009 and the one of dietary treatment in 2010. One conclusion was that less frequent use of test strips by patients with diabetes would save 5–9 million euros each year without increasing medical risks. Group-based patient education with trained healthcare professionals significantly lowers long-term blood glucose levels, but motivational interviewing is not more effective than usual care.
While it is too early to assess impact, the National Board of Health and Welfare has used all three reports in designing its guidelines. The conclusions point to major potential for efficiency gains in the healthcare system.
There is scientific evidence that therapeutic hypothermia for newborns with moderate to severe symptoms of hypoxic ischaemic encephalopathy due to serious perinatal asphyxia reduces the risk of death or severe disability. But the evidence is insufficient to assess the efficacy of the method for longer than 18 months. Further research is urgently needed to determine optimum clinical practice while identifying any complications or adverse effects that may arise.
The method was being used by ten large hospitals at the time the report was published. Additional hospitals have now purchased the equipment needed to provide the treatment.
It cannot be determined whether leukocytapheresis for moderate to severe ulcerative colitis is more effective than conventional therapy with corticosteroids or placebo. The studies that have compared leukocytapheresis to steroid therapy suggest that their effectiveness is similar. Well-designed and sufficiently large studies must be conducted to assess the efficacy of the method for inflammatory bowel disease.
Leukocytapheresis causes fewer and milder adverse effects than steroid therapy during the period of treatment. But knowledge is lacking concerning potential long-term adverse effects of leukocytapheresis.
Although no impact can be assessed yet, follow-up will proceed from the Swedish Therapeutic Apheresis Registry, which has the status of a national quality registry. Annual follow-ups will be published at www.kvalitetsregister.se. In addition, the Swedish Apheresis Group conducted a survey in autumn 2008 concerning Adacolumn treatment.
Caries is the most common cause of toothache and loss of teeth. Laser technology is a new method for removing hard dental tissue damaged by caries. The technology is just as effective as drilling but takes more time. There is insufficient scientific evidence to assess the impact of the technology on dental pulp or the subsequent lifetime of the filling. Evidence is lacking to draw any reliable conclusions about the cost-effectiveness of the method. Given that it appears to be no more effective than drilling for removing hard dental tissue but is undeniably more expensive, it cannot be regarded as cost-effective at the present.
The National Board of Health and Welfare is using the report to draw up its guidelines. Due to the limited research that has been conducted, the Board’s prioritisation group may place laser technology for removal of caries far down on its list. The Dental and Pharmaceutical Benefits Agency will then determine whether the treatment is to be covered by the high-cost ceiling and set a reference price. Its use is likely to spread slower if it is not covered by the ceiling.
SBU published an Alert-report on home blood pressure (BP) monitoring in 2010 which created a lot of mass media attention. The report concluded that BP monitoring by the patient at home is at least as accurate as monitoring in a health care setting and it may save costs.
The sale of home blood pressure monitoring devices was more than doubled immediately after the release of the report. This sale increase stopped after some months which indicates there are no real incentives for health care to promote home blood pressure monitoring.
SBU reports of methods to prevent mental ill-health in children, tooth loss and endodontics (root canal therapy) showed lack of scientific knowledge in many areas.
The SBU report of methods to prevent mental ill-health in children contributed together with projects from the Royal Swedish Academy of Sciences promoted a strong general call for research on childrens health on 30 million euros from several research councils in Sweden.
SBU and the Swedish Research Council initiated together with the National Board of Health and Welfare, the Swedish Association of Local Authorities and Regions and The Swedish Dental Association national workshops and coalitions on how to answer research questions concerning knowledge gaps.
SBU has an information and inquiry service where decision-makers and health care personnel can ask question concerning the magnitude of evidence for methods which is suggested for introduction or are already in-operation in health care.
According to a survey, the inquiry service is very much appreciated by the users and several decisions have been taken based on answers from the inquiry service. Examples of methods that were not introduced due to answers from the inquiry service were routine ultrasonography in the third trimester of pregnancy, manual lymphatic drainage therapy and autologous chondrocyte transplantation.
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