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The original series Protocols for Investment in Health Gain were written in the early 1990s to suggest areas where the introduction, or more widespread use, of certain practices could lead to worthwhile improvements in health for the people of Wales. This revision has been prepared by reviewing the osteoporosis section in the earlier Protocol for Investment in Health Gain: Physical Discomfort & Disability to provide some clear, updated statements with a precise indication of the strength of the evidence and its sources for each statement. The bulletin also introduces new statements covering recent developments and subjects of important current interest.
The statements represent a methodical summary of the evidence in this area found through a formal literature search across a wide range of sources2. The evidence has been critically appraised using internationally accepted methods2, compiled into this document under the direction of a public health physician, and reviewed by a multidisciplinary team who are directly involved in patient care. The information in this document is also available electronically, via the NHS Cymruweb (http://nww.wales.nhs.uk/hebw) and the Internet (http://hebw.cardiff.ac.uk). Information on the methodology adopted (including a copy of the documentation), the formats in which the document is issued and details of other publications in the series are available on request.
TopThe convention used in this document to indicate the type of evidence is:
| ‘Type I evidence’ - at least one
good systematic review (including at least one randomised controlled trial). ‘Type II evidence’ - at least one good randomised controlled trial ‘Type III evidence’ - well designed interventional studies without randomisation ‘Type IV evidence’ - well designed observational studies ‘Type V evidence’ - expert opinion; influential reports and studies |
The use of evidence type rather than evidence hierarchy has been chosen deliberately. Every attempt has been made to find the best available evidence in support of statements in this bulletin. Information from high quality intervention studies is included whenever possible but observational evidence is also cited where relevant. By valuing evidence from randomised controlled trials more highly than observational studies there is a danger that interventions with limited effectiveness might be judged to be more worthy than those based on observation. Similarly, those observational studies which clearly prove effectiveness (and make a randomised trial unethical) might be undervalued. Information assigned as Type V evidence may include expert opinion and important reports or recommendations which should also be highly regarded.
TopThe health gain notation (used to indicate the potential benefit to health) is
| (1) ‘beneficial’ - effectiveness clearly demonstrated |
| (2) ‘likely to be beneficial’ - effectiveness not so firmly established |
| (3) ‘trade-off between beneficial and adverse effects’ - effects weighed according to individual circumstances |
| (4) ‘unknown’ - insufficient/inadequate for recommendation |
| (5 ‘unlikely to be beneficial’ - ineffectiveness is not as clearly demonstrated as for (6) |
| (6) ‘likely to be ineffective or harmful’ - ineffectiveness or harm clearly demonstrated |
It should be stressed that these gradings, while aiming to be impartial, represent only the best advice of the professionals involved in preparing the Bulletin. Where possible the health gain notation reflects both the type of evidence and the small size of some of the samples. Although the statements are deliberately brief, statistically significant quantitative information has been provided where possible. Issues of cost-effectiveness or cost-benefit are considered where evidence is available.
TopThe Osteoporosis Health Evidence Bulletin
The statements made in this bulletin present a graded summary of the best available evidence of effectiveness in the prevention and management of osteoporosis. The following information sources were systematically searched in the preparation of this Bulletin: Cochrane Library, Medline, Pre-Medline, Embase, CINAHL, ASSIA, Rehabdata, National Research Register, NEED, Health Promis, the TRIP database, AMED, SIGLE, Science Citation Index, Best Evidence, PEDRO, Clinical Evidence, Evidence-Based Health Technology Appraisal and Guidelines sites. Databases were searched using the textword osteoporo* (truncated to search for osteoporosis & osteoporotic) and relevant thesauri or subject headings for osteoporosis in individual databases. Searches were carried out using specific search filters (where possible) to search for research publications in the sequential order given in the evidence type classification shown above (systematic reviews of randomised controlled trials, then randomised controlled trial, and so on). Details of these information sources, search strategies for specific types of research and the critical appraisal techniques used are provided in the Project Methodology2. With the exception of the Cochrane Library (where Issue 4, 2001 was examined), all databases were searched for publications up to and including December 2000. Some additional references were obtained via reference list follow-up and recommendation from review group members, including a number of papers published in 2001.
The authors recognise that a large number of systematic reviews and evidence-based guidelines have already been published on osteoporosis and it is hoped that the vast majority are cited in this Bulletin. A number of statements refer to the excellent evidence-based guidelines recently published by the Royal College of Physicians (RCP),. In the preparation of this publication, we aimed to concentrate on research papers published since the date of the comprehensive literature search used to prepare the RCP guidelines6. Thus, we sought publications from 1998 onwards as described above, ensuring that the additional research papers cited in the July 2000 update of the RCP guidelines7 were also included.
TopAs well as examining the management of low bone mineral density and osteoporosis in women and men, some specific issues have also been covered in detail: The epidemiology of osteoporosis (including risk and prevention factors), ultrasound versus dual x-ray absorptiometry for screening and monitoring of treatment, corticosteroid-induced osteoporosis & transplantation issues, and osteoporosis in children.
In keeping with the original Protocols, these revised documents are designed to assist planners and commissioners of healthcare in developing local strategies and in commissioning high quality health care. It is anticipated that they will also be of value to all professionals involved in delivering services for people with, or at risk from, osteoporosis in keeping abreast of the large and increasing body of literature in this field. It should be stressed that the publications will act as a supplement to, not a substitute for, skills and experience. Some of the conclusions reached in this bulletin will inevitably be controversial. Every effort has been made to include the best evidence within a subject area. Readers who are aware of any important studies that have been overlooked are encouraged to contact the project team3.
While every effort is made to avoid errors in these summaries, the statements are intended to act as signposts to reliable sources of evidence, not as guidelines for the management of patients. It is hoped that this bulletin will facilitate evidence-based practice, which involves "integrating individual expertise with the best available external evidence from systematic research".
November 2001
TopGlossary of Abbreviations used in this Bulletin
| BMC: | Bone mineral content |
| BMD: | Bone mineral density |
| BUA: | Broadband ultrasound attenuation |
| 95% CI: | 95% confidence interval |
| DEXA/DXA: | Dual-energy x-ray absorptiometry |
| ERT: | Estrogen replacement therapy |
| HRT: | Hormone replacement therapy (oestrogen only or oestrogen + progesterone) |
| NNT: | Number Needed to Treat |
| OR: | Odds Ratio |
| QUS: | Quantitative ultrasound |
| RCT: | Randomised controlled trial |
| RH: | Relative Hazard |
| RR: | Relative Risk |
| QUS: | Quantitative ultrasound |
| SD: | Standard deviation |
| SEM: | Standard Error of the Mean |
| SOS: | Speed of Sound |
| T score: | Skeletal mass given as SD units away from the mean value for a young healthy population |
| WHO: | World Health Organisation |
| Z score: | Skeletal mass given as SD units away from the mean value for an age-matched cohort |
Health Evidence Bulletins: Wales, Duthie Library, UWCM, Cardiff CF14 4XN. e-mail: weightmanal@cardiff.ac.uk