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Stevens A, Spooner D. Lacrimal Duct Stenosis and Other Ocular Toxicity Associated with Adjuvant Cyclophosphamide, Methotrexate and 5-Fluorouracil Combination Chemotherapy for Early Stage Breast Cancer. Clin Oncol (R Coll Radiol) 2001. [DOI: 10.1007/s001740170008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Parry J, Stevens A. Prospective health impact assessment: pitfalls, problems, and possible ways forward. BMJ (CLINICAL RESEARCH ED.) 2001; 323:1177-82. [PMID: 11711414 PMCID: PMC1121649 DOI: 10.1136/bmj.323.7322.1177] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Kendrick T, Stevens L, Bryant A, Goddard J, Stevens A, Raftery J, Thompson C. Hampshire depression project: changes in the process of care and cost consequences. Br J Gen Pract 2001; 51:911-3. [PMID: 11761205 PMCID: PMC1314148] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/23/2023] Open
Abstract
Records of patients included in a trial of educating practice teams about the management of depression were examined to determine changes in the process of care. There were no significant differences in the proportions recognised or treated for depression. Only 15% of those with possible, and 26% of those with probable, major depressive disorder were prescribed recommended doses and duration of antidepressants. The education apparently delayed a switch away from tricyclics while achieving a similar outcome. However health service costs were mainly non-psychiatric, and there were no significant savings as a result.
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Stevens A, Kircher T, Nickola M, Bartels M, Rosellen N, Wormstall H. Dynamic regulation of EEG power and coherence is lost early and globally in probable DAT. Eur Arch Psychiatry Clin Neurosci 2001; 251:199-204. [PMID: 11829205 DOI: 10.1007/s004060170027] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
Electroencephalographic (EEG) findings in dementia of Alzheimer type (DAT) include slowing of alpha frequency, loss of alpha band power, increased theta and delta power and reduced coherence. Here it is evaluated whether a) EEG acquisition during different functional states facilitates the detection of DAT-associated EEG changes, and b) EEG changes in mild DAT are topographically confined or global. Power spectra and coherence of EEGs from 29 patients with mild probable DAT and 28 age- and sex-matched controls were compared during three cognitive states. Group differences in power spectra and coherence were largest during resting with eyes open, yielding a 77% correct classification result. Already in early stages of probable DAT, EEG changes were topographically wide-spread. The task-related up- and down-regulation of power and coherence was impaired already in mild probable DAT. We propose to augment clinical EEG assessment by including a quantitative analysis of the dynamic power and coherence changes from rest, eyes closed to eyes open in suspected DAT.
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Stevens A, Ray D, Alansari A, Hajeer A, Thomson W, Donn R, Ollier WE, Worthington J, Davis JR. Characterization of a prolactin gene polymorphism and its associations with systemic lupus erythematosus. ARTHRITIS AND RHEUMATISM 2001; 44:2358-66. [PMID: 11665977 DOI: 10.1002/1529-0131(200110)44:10<2358::aid-art399>3.0.co;2-k] [Citation(s) in RCA: 64] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
OBJECTIVE Hyperprolactinemia is associated with systemic lupus erythematosus (SLE), but the mechanism is unknown. Prolactin is expressed in T lymphocytes and is under the control of an alternative promoter region. We characterized a G/T single-nucleotide polymorphism (SNP) at position -1149 of this promoter and assessed its prevalence in patients with SLE. METHODS Electrophoretic mobility shift assays (EMSAs) were performed to determine DNA protein complex formation in the prolactin promoter. Transient transfection of reporter gene constructs containing the G/T promoter alleles into the Jurkat T cell line were used to determine transcription activity. Peripheral blood lymphocytes (PBLs) were treated in vitro with phytohemagglutinin (PHA) to determine levels of prolactin messenger RNA (mRNA). RESULTS EMSAs indicated that binding of a GATA-related transcription factor was altered by the G/T SNP at position -1149. Transient transfection studies in Jurkat cells showed that the G allele consistently produced higher promoter activity. PHA treatment of PBLs in vitro induced a greater increment of prolactin mRNA from patients with the GG(-1149) genotype than from those with the TT(-1149) genotype. Disease association studies in a cohort of SLE patients demonstrated an increased frequency of the prolactin -1149 G allele compared with control subjects. CONCLUSION We found a functionally significant polymorphism that alters prolactin promoter activity and mRNA levels in the lymphocytes. Altered local prolactin production by immune cells may contribute to disease progression by affecting T cell function.
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Marshall T, Simpson S, Stevens A. Health care needs assessment in prisons: a toolkit. JOURNAL OF PUBLIC HEALTH MEDICINE 2001; 23:198-204. [PMID: 11585192 DOI: 10.1093/pubmed/23.3.198] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND Since 1999, prison health services and health authorities have been jointly responsible for assessing the health care needs of the prison population. To facilitate this process, the Department of Public Health and Epidemiology at the University of Birmingham developed a toolkit for carrying out a health care needs assessment of the prison population. METHODS This paper describes the principles of the epidemiological approach to needs assessment and presents a stepped approach to carrying out a health care needs assessment in prisons. Some examples of the kind of health care needs to be found in prisons are presented. RESULTS A systematic approach to the assessment of the health care needs of prisoners ensures that all the essential components of this important planning exercise are considered. The prison population is described, health problems are identified and quantified, and a review of current services is carried out. This allows the most effective solutions to addressing the health problems to be established. The process can be time consuming and is reliant on good data sources, but it does ensure that health problems and service elements are considered and addressed together rather than in a disjointed manner. CONCLUSION The stepped approach to epidemiological needs assessment allows health problems and current services to be identified. It also allows these to be matched to appropriate service requirements.
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Lilford RJ, Braunholtz D, Edwards S, Stevens A. Monitoring clinical trials--interim data should be publicly available. BMJ (CLINICAL RESEARCH ED.) 2001; 323:441-2. [PMID: 11520848 PMCID: PMC1121037 DOI: 10.1136/bmj.323.7310.441] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
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Burgio L, Lichstein KL, Nichols L, Czaja S, Gallagher-Thompson D, Bourgeois M, Stevens A, Ory M, Schulz R. Judging outcomes in psychosocial interventions for dementia caregivers: the problem of treatment implementation. THE GERONTOLOGIST 2001; 41:481-9. [PMID: 11490046 PMCID: PMC2577189 DOI: 10.1093/geront/41.4.481] [Citation(s) in RCA: 89] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
PURPOSE In published dementia caregiver intervention research, there is widespread failure to measure the level at which treatment was implemented as intended, thereby introducing threats to internal and external validity. The purpose of this article is to discuss the importance of inducing and assessing treatment implementation (TI) strategies in caregiving trials and to propose Lichstein's TI model as a potential guide. DESIGN AND METHODS The efforts of a large cooperative research study of caregiving interventions, Resources for Enhancing Alzheimer's Caregiver Health (REACH), illustrates induction and assessment of the three components of TI: delivery, receipt, and enactment. RESULTS The approaches taken in REACH vary with the intervention protocols and include using treatment manuals, training and certification of interventionists, and continuous monitoring of actual implementation. IMPLICATIONS Investigation and description of treatment process variables allows researchers to understand which aspects of the intervention are responsible for therapeutic change, potentially resulting in development of more efficacious and efficient interventions.
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Stevens A, Minton R. In-vehicle distraction and fatal accidents in England and Wales. ACCIDENT; ANALYSIS AND PREVENTION 2001; 33:539-545. [PMID: 11426684 DOI: 10.1016/s0001-4575(00)00068-3] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
The paper describes the coding and analysis of a database of police fatal accident reports to investigate the extent to which in-vehicle distraction is a contributory factor in vehicle crashes. A particular focus has been the involvement of mobile telephones and entertainment systems. Analysis of accidents occurring over the period 1985-1995 shows that in-vehicle distraction is reported as a contributory factor in about 2% of fatal accidents (although this figure may be a conservative estimate). Specific examples of distraction attributed to entertainment systems and telephones have been identified. Electronic driver information systems are also of particular interest, but have not featured in the available data. Work is progressing, on an annual cycle, to obtain, code and analyse further data and this is expected to provide an invaluable source of information for accident researchers.
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Schwarz J, Klotz A, Bräuer K, Stevens A. Master-slave synchronization in chaotic discrete-time oscillators. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2001; 64:011108. [PMID: 11461226 DOI: 10.1103/physreve.64.011108] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2000] [Revised: 03/21/2001] [Indexed: 05/23/2023]
Abstract
In this paper, we study a simple discrete-time neural oscillator model that, in certain parameter regimes, exhibits periodic or chaotic dynamics. The present model with intrinsically chaotic dynamics is capable of spatiotemporal information processing: in response to constant external stimulation, the oscillator can switch into different chaotic states restricted to distinct parts of the phase space. Of particular interest is the processing of time-dependent input in a master-slave configuration of two coupled oscillators. Here, the response of an oscillator is studied by driving it with the signal of the other. Following the input, the response system adapts to the state of the drive. For a chaotic drive, we can observe generalized synchronization. The onset of adaptation to the drive state by the response is accompanied by on-off intermittency resulting in irregular bursting behavior.
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Halliday I, Hammond LA, Care CM, Good K, Stevens A. Lattice Boltzmann equation hydrodynamics. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2001; 64:011208. [PMID: 11461241 DOI: 10.1103/physreve.64.011208] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/16/2000] [Revised: 01/02/2001] [Indexed: 05/23/2023]
Abstract
By inserting position and time dependent "source" or "forcing" terms into the microscopic evolution equation of a lattice Boltzmann fluid and treating the generalized scheme within the usual Chapman-Enskog methodology, we show that the emergent dynamics of the lattice fluid may be usefully transformed. Our method of adjustment is demonstrated by implementing the cylindrical polar coordinate form of the continuity and momentum equations on a rectangular lattice and generating results for pipe flow. With straightforward systematic adjustment of the simulation, our approach produces results in excellent agreement with theory.
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Jobling AI, Stevens A, Augusteyn RC. Binding of dexamethasone by alpha-crystallin. Invest Ophthalmol Vis Sci 2001; 42:1829-32. [PMID: 11431449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/20/2023] Open
Abstract
PURPOSE Long-term steroid therapy is a known risk factor for the development of posterior subcapsular cataract. Previous work in this laboratory has found soluble lens proteins to bind dexamethasone, but this binding is not due to a glucocorticoid receptor. This study was undertaken to identify the soluble protein or proteins involved in lens glucocorticoid binding. METHODS Bovine lens extract was incubated with 5.2 x 10(-)(8) M [(3)H]-dexamethasone for 3 hours, and the distribution of label assessed in the soluble and insoluble fractions after centrifugation. Soluble lens extract was fractionated using gel permeation chromatography to isolate and identify proteins involved in the binding. Total lens proteins, high-molecular-weight proteins, or alpha-crystallin were exposed to dexamethasone and the protein bound steroid measured after separation of free and bound ligand on a gel chromatography column. Scatchard analysis was used to determine dexamethasone-binding parameters. Sequence comparisons between bovine alphaA- and alphaB-crystallins and glucocorticoid-binding proteins were performed using a sequence-alignment program. RESULTS Of the total dexamethasone bound in lens extract, soluble proteins were found to account for 52%. The majority of the soluble protein-bound dexamethasone coeluted with the high-molecular-weight proteins that consisted mainly of alpha-crystallin. Binding studies with isolated proteins showed that alpha-crystallin accounted for more than 98% of total soluble dexamethasone binding in the lens. Scatchard analysis of steroid binding showed it to be a nonspecific partitioning event. Sequence comparisons between alphaA- and alphaB-crystallins and various glucocorticoid-binding proteins showed the lens proteins to have three regions of sequence homology with yeast corticosteroid-binding protein. CONCLUSIONS alpha-Crystallin is the principal soluble glucocorticoid binding protein in the lens. The steroid association is described by nonspecific partitioning and may be related to the unique structural characteristics of the protein. The nonspecific association with alpha-crystallin is not thought to be functional; however, it may aid in the increased covalent steroid modification observed for this protein.
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Jolly K, Parry J, Rouse A, Stevens A. Volumes of cancer surgery for breast, colorectal and ovarian cancer 1992-97: Is there evidence of increasing sub-specialization by surgeons? Br J Cancer 2001; 84:1308-13. [PMID: 11355939 PMCID: PMC2363641 DOI: 10.1054/bjoc.2001.1794] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
The ‘Calman–Hine Report’ (1995) recommended that cancer surgery should be limited to ‘high-volume’ consultants. Through an analysis of 5 years of Hospital Episode Statistics for the West Midlands region (1992–1997), we have investigated whether there is evidence of increasing numbers of patients with breast, colorectal or ovarian cancer being treated by high throughput, i.e. sub-specialist surgeons, who carry out more than a threshold level of primary cancer resections annually. The proportion of cases treated by the high-volume breast, colorectal and ovarian cancer surgeons increased annually during the 5 years. The absolute number of consultant firms who undertook breast cancer resections reduced during the 5 years; but the number doing colorectal and ovarian surgery increased. Throughout the 5 years, half of the ovarian cancer resections were carried out by consultant firms who did very few procedures – less than 5 of these procedures annually. The relatively high case-load, the elective nature of breast cancer surgery and an early policy change have undoubtedly facilitated the move towards sub-specialization. The weaker trends for colorectal and ovarian cancer surgery suggest continued monitoring is required to ensure that there is a reduction in the proportion of people treated by surgeons who undertake few cancer resections annually. © 2001 Cancer Research Campaign www.bjcancer.com
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Battye R, Stevens A, Perry RL, Jacobs JR. Repellent signaling by Slit requires the leucine-rich repeats. J Neurosci 2001; 21:4290-8. [PMID: 11404414 PMCID: PMC6762740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/04/2001] [Revised: 03/23/2001] [Accepted: 03/23/2001] [Indexed: 02/20/2023] Open
Abstract
Slit is a repellent axon guidance cue produced by the midline glia in Drosophila that is required to regulate the formation of contralateral projections and the lateral position of longitudinal tracts. Four sequence motifs comprise the structure of Slit: a leucine-rich repeat (LRR), epidermal growth factor-like (EGF) repeats, a laminin-like globular (G)-domain, and a cysteine domain. Here we demonstrate that the LRR is required for repellent signaling and in vitro binding to Robo. Repellent signaling by slit is reduced by point mutations that encode single amino acid changes in the LRR domain. By contrast to the EGF or G-domains, the LRR domain is required in transgenes to affect axon guidance. Finally, we show that the midline repellent receptor, Robo, binds Slit proteins with internal deletions that also retain repellent activity. However, Robo does not bind Slit protein missing the LRR. Taken together, our data demonstrate that Robo binding and repellent signaling by Slit require the LRR region.
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McManus P, Birkett DJ, Dudley J, Stevens A. Impact of the Minimum Pricing Policy and introduction of brand (generic) substitution into the Pharmaceutical Benefits Scheme in Australia. Pharmacoepidemiol Drug Saf 2001; 10:295-300. [PMID: 11760489 DOI: 10.1002/pds.603] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
PURPOSE To describe the effects of introducing the Minimum Pricing Policy (MPP) and generic (brand) substitution in 1990 and 1994 respectively on the dispensing of Pharmaceutical Benefits Scheme (PBS) prescriptions both at the aggregate and individual patient level. METHODS The relative proportion of prescriptions with a brand premium and those at benchmark was examined 4 years after introduction of the MPP and again 5 years later after generic substitution by pharmacists was permitted. To determine the impact of a price signal at the individual level, case studies involving a patient tracking methodology were conducted on two drugs (fluoxetine and ranitidine) that received a brand premium. RESULTS From a zero base when the MPP was introduced in 1990, there were 5.4 million prescriptions (17%) dispensed for benchmark products 4 years later in 1994. At this stage generic (brand) substitution by pharmacists was then permitted and the market share of benchmark brands increased to 45% (25.2 million) by 1999. In the patient tracking studies, a significantly lower proportion of patients was still taking the premium brand of fluoxetine 3 months after the introduction of a price signal compared with patients taking paroxetine which did not have a generic competitor. This was also the case for the premium brand of ranitidine when compared to famotidine. The size of the price signal also had a marked effect on dispensing behaviour with the drug with the larger premium (fluoxetine) showing a significantly greater switch away from the premium brand to the benchmark product. CONCLUSIONS The introduction in 1990 of the Minimum Pricing Policy without allowing generic substitution had a relatively small impact on the selection of medicines within the Pharmaceutical Benefits Scheme. However the effect of generic substitution at the pharmacist level, which was introduced in December 1994, resulted in a marked increase in the percentage of eligible PBS items dispensed at benchmark. Case studies showed a larger premium resulted in a greater shift of patients from drugs with a brand premium to the benchmark alternative.
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Saunders P, Mathers J, Parry J, Stevens A. Identifying 'non-medical' datasets to monitor community health and well-being. JOURNAL OF PUBLIC HEALTH MEDICINE 2001; 23:103-8. [PMID: 11450925 DOI: 10.1093/pubmed/23.2.103] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
BACKGROUND The aim of the study was to identify 'non-medical' datasets holding routinely collected information that might be used to measure and monitor the wider determinants of community health and well-being. METHODS An expert panel discussion, involving public health and environmental health academics and professionals with expertise in a variety of backgrounds (including environmental health, housing, transport, community safety, public health, primary and secondary care), and interrogation of the Office for National Statistics database were carried out for the West Midlands region. The aim was to identify routinely collected 'non-medical' datasets containing information on the following factors: physical environment, crime, housing and homelessness, social services, socio-economic environment including employment, lifestyles, education, leisure and culture, transport and accidents. RESULTS Fifty-six datasets were identified. Although 43 (77 per cent) were collected at least annually, few (17; 30 per cent) held data that were disaggregated and routinely available at the sub-local authority level. CONCLUSIONS This study has identified a number of datasets that hold information relevant to health. However, no single dataset is likely to provide information on all dimensions of health and the determinants of health, and local agencies should consider carefully the strengths and weaknesses of each. Through the development of inter-sectoral working and multi-agency involvement at the local level there is now considerable scope to improve the quality of many of these datasets and to promote their use in the measurement and monitoring of community health.
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Marshall T, Simpson S, Stevens A. Use of health services by prison inmates: comparisons with the community. J Epidemiol Community Health 2001; 55:364-5. [PMID: 11297662 PMCID: PMC1731884 DOI: 10.1136/jech.55.5.364] [Citation(s) in RCA: 63] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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Stevens A. Antiferromagnetic dispersion, absorption and light scattering in NiO and other face centred cubic crystals. ACTA ACUST UNITED AC 2001. [DOI: 10.1088/0022-3719/5/14/011] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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Rouse A, Wilson R, Stevens A. If the NHS introduced a '50 procedures a year' policy, what proportion of consultant firms would be affected? JOURNAL OF PUBLIC HEALTH MEDICINE 2001; 23:65-8. [PMID: 11315697 DOI: 10.1093/pubmed/23.1.65] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Abstract
BACKGROUND Governments, insurers, quality assurance agencies and others have used the higher volume = better quality relationship as a basis for health policy. This relationship is probably real enough to justify these policies. However, even if it were not real, there are other reasons why these and other organizations such as the National Health Service (NHS) may favour high-volume providers. This paper attempts to answer the question: 'If, for common elective procedures, the NHS instituted a high-volume purchasing policy that requires consultant firms to perform a minimum of "50 procedures a year", what proportion of consultant firms would be affected?' The aims of this study were to estimate the proportion of NHS consultant firms that perform common elective procedures less than 50 times a year and to estimate the proportion of firms that would have to stop providing these procedures if a '50 procedures a year' purchasing policy were introduced. METHOD A descriptive analysis was carried out and modelling was performed on data stored in an NHS health episode statistics database of patients treated in West Midlands NHS facilities. For each of 12 common elective procedures we assumed that a volume threshold of at least 50 a year were set, and calculated the proportion of NHS consultant firms undertaking each procedure who performed less than 50 of those procedures each year and the proportion of firms who would have had to stop providing each procedure. RESULTS All firms performing some procedures, e.g. cataract extraction, did so at least 50 times a year. By contrast, no firm repaired more than 50 recurrent inguinal hernias a year. If a volume threshold of at least 50 procedures a year were set for a basket of 12 common elective procedures, then about 40 per cent of firms would no longer be eligible to provide a procedure. Even if a lower 'one a month' threshold were set, about 20 per cent of firms would still not be eligible to provide that procedure. CONCLUSION Introduction of a high-volume policy would affect a considerable number of firms, as many NHS consultant firms perform some common elective procedures infrequently. Some consultants would see the introduction of a high-volume policy as an opportunity to further specialize and super-specialize. Others would see it as a policy that restricts them to providing a narrower range of procedures, makes their professional practice less interesting, and reduces their professional autonomy. Postgraduate training institutions need to consider the possibility and implications of high-volume policies, as many junior doctors would probably need to learn to provide a narrower range of skills than at present.
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Stevens A, Price J. Evolutionary theory and psychiatry. Br J Psychiatry 2001; 178:277-8. [PMID: 11230042 DOI: 10.1192/bjp.178.3.277-b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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221
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Stevens A, Hammer K, Buchkremer G. A statistical model for length of psychiatric in-patient treatment and an analysis of contributing factors. Acta Psychiatr Scand 2001; 103:203-11. [PMID: 11240577 DOI: 10.1034/j.1600-0447.2001.00043.x] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
OBJECTIVE Direct illness costs in psychiatry are strongly related to the length of in-patient stay (LOS). Prior studies have shown that LOS depends upon many factors; however, there is no systematic work on their interrelation and relative contribution. METHOD A detailed statistical analysis of the factors explaining LOS for n = 4,706 consecutive admissions (1994-97) to the psychiatric hospital of the University of Tübingen is presented. RESULTS The distribution of LOS follows an exponential decay function, suggesting a hazard-based process. Cox regression indicates that the incidence of discharge and hence LOS is modulated by a number of illness-related and other factors, and their relationship is explored. CONCLUSION While a linear model is commonly assumed, LOS in psychiatry is governed by a hazard-based process. As a tool in quality management, LOS data for psychiatric hospitals might be routinely analyzed and the effects of non-illness-related factors minimized.
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Chase D, Milne R, Stein K, Stevens A. What are the relative merits of the sources used to identify potential research priorities for the NHS HTA programme? Int J Technol Assess Health Care 2001; 16:743-50. [PMID: 11028130 DOI: 10.1017/s0266462300102028] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
The NHS Health Technology Assessment (HTA) Programme runs an annual process of identifying suggestions for health technology assessment. The objective of this paper is to describe and evaluate the relative importance of the different sources used by the program in 1998 to identify potential priorities. There were four different sources: a) a widespread consultation of healthcare commissioners, providers and consumers; b) research recommendations from systematic reviews; c) reconsidering previous research priorities which had not been taken forward for funding; and d) horizon scanning. Collectively, the four sources generated just over 1,100 HTA suggestions. By far the largest source of suggestions and priorities was the widespread consultation. However, the success rate of this source, in terms of being commissioned, was low. Research recommendations from systematic reviews provided the second largest source of priorities and the best success rate of all sources. Value was found from different sources for different healthcare areas.
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Meads C, Cummins C, Jolly K, Stevens A, Burls A, Hyde C. Coronary artery stents in the treatment of ischaemic heart disease: a rapid and systematic review. Health Technol Assess 2001; 4:1-153. [PMID: 11074393] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023] Open
Abstract
BACKGROUND Coronary artery stents are prosthetic linings inserted into coronary arteries via a catheter to widen the artery and increase blood flow to ischaemic heart muscle. They are used in the treatment of ischaemic heart disease (IHD). IHD is a major cause of morbidity and mortality (123,000 deaths per annum) in the UK and a major cost to the NHS. Clinical effects of IHD include subacute manifestations (stable and unstable angina) and acute manifestations (particularly myocardial infarction [MI]). Treatment includes attention to risk factors, drug therapy, percutaneous invasive interventions (PCIs) (including percutaneous transluminal coronary angioplasty [PTCA] and stents) and coronary artery bypass graft surgery (CABG). In the last decade there has been a steady and significant increase in the rate of PCIs for IHD. In the UK, rates per million population increased from 174 in 1991 to 437 in 1998. Stents are now used in about 70% of PCIs. Data from the rest of Europe suggest there is potential for PCI and stent rates to increase considerably. In the UK there is evidence of under-provision and inequity of access to revascularisation procedures. OBJECTIVES The following questions were addressed. 1. What are the effects and effectiveness of elective stent insertion versus PTCA in subacute IHD, particularly stable angina and unstable angina? 2. What are the effects and effectiveness of elective stent insertion versus CABG in subacute IHD, particularly stable angina and unstable angina? 3. What are the effects and effectiveness of elective stent insertion versus PTCA in acute MI (AMI)? 4. What are best estimates of UK cost for elective stent insertion, PTCA and CABG in the circumstances of review questions 1 to 3? 5. What are best estimates of cost-effectiveness and cost-utility for elective stent insertion relative to PTCA or CABG in the circumstances of review questions 1 to 3? METHODS A systematic review addressing the objectives was undertaken. DATA SOURCES A search was made for RCTs comparing stents (inserted during a PTCA procedure) with PTCA alone or with CABG in any manifestation of IHD. The search strategy covered the period from 1990 to November 1999 and included searches of electronic databases (MEDLINE, EMBASE, BIDS ISI, The Cochrane Library), Internet sites, and hand-searches of cardiology conference abstracts and 1999 issues of cardiology journals. Lead researchers and local clinical experts were contacted. Manufacturers' submissions to the National Institute for Clinical Excellence were searched. The search strategy was expanded to look for relevant economic analyses and information to inform the economic model (including searching MEDLINE, the NHS Economic Evaluation Database and the Database of Abstracts of Reviews of Effectiveness). Searches focused on research that reported costs and quality of life data associated with IHD and interventional cardiology. STUDY SELECTION For the review of clinical effectiveness, inclusion criteria were: (i) RCT design; (ii) study population comprising adults with IHD in native or graft vessels (including patients with subacute IHD or AMI); (iii) procedure involving elective insertion of coronary artery stents; (iv) elective PTCA (including PTCA with provisional stenting) or CABG as comparator; (v) outcomes defined as one or more of: combined event rate (or event-free survival), death, MI, angina, target vessel revascularisation, CABG, repeat PTCA, angiographic outcomes; (vi) trials that had closed and reported results for all or almost all recruited patients. For the economic evaluation, studies of adults with IHD were included if they were of the following types: studies reporting UK costs; comparative economic evaluation combining both costs and outcomes; economic evaluations reporting costs and outcomes separately for the years 1998 and 1999 (to ensure current practice was included).(ABSTRACT TRUNCATED)
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Booth-Clibborn N, Packer C, Stevens A. Health technology diffusion rates. Statins, coronary stents, and MRI in England. Int J Technol Assess Health Care 2001; 16:781-6. [PMID: 11028133 DOI: 10.1017/s0266462300102053] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
OBJECTIVE To analyze the rates and influences on the adoption of three selected health technologies: statins, coronary stents, and magnetic resonance imaging (MRI). METHODS A retrospective diffusion study using primary care prescribing data and questionnaire responses from acute hospital trusts in the West Midlands region (population 5.3 million or 10% of England). RESULTS The selected technologies had markedly different diffusion curves. Statins diffused rapidly soon after launch. Coronary stents were initially used 6 years after first availability, but within 2 years all responding hospitals reported using them. MRI scanners were initially purchased 6 years after first availability with a subsequently slow rate of diffusion, and are still absent from some hospitals. Influences on the adoption of each technology were different. Commercial marketing was reported as a major influence on the diffusion of statins but not at all on MRIs. Cost impact was a major negative influence on the diffusion of MRI scanners and statins, whereas enthusiastic individuals were key to the diffusion of stents. CONCLUSIONS Influences on adoption and consequent diffusion rates are very different for different health technologies. It is not at all clear that such diffusion patterns relate well to an optimum timing rate. This has important implications for technology gatekeepers in health care.
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Lilford RJ, Richardson A, Stevens A, Fitzpatrick R, Edwards S, Rock F, Hutton JL. Issues in methodological research: perspectives from researchers and commissioners. Health Technol Assess 2001; 5:1-57. [PMID: 11368832 DOI: 10.3310/hta5080] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
OBJECTIVES (1) Methodological research has few well-defined tools and processes analogous to those available for reviews and data collection in substantive health technology assessment. (2) This project was set up to obtain researchers' and others' views on the innovative projects on research methodology under the NHS Health Technology Assessment Programme and the usefulness of the research. (3) The study was intended to span both epistemological and management issues. (4) The following issues were explored: (a) the degree to which researchers would feel constrained by the "Cochrane" approach to systematic reviews when undertaking reviews of a methodological nature; (b) whether methodological projects may require exceptional design and management arrangements, in view of their novelty, subjectivity and complexity; (c) whether researchers would seek out other methods, in addition to undertaking reviews of argument, as a means of extending their understanding of methodological issues (there may be three categories of research methods in methodology: reviews of methodological argument, studies that use the literature as a source of data, and research that collects new primary data); (d) whether the Methodology Programme overall can be considered a "success". METHODS (1) Telephone interviews were carried out on researchers (one senior and one junior per project), resulting in 35 interviews from 19 of the 20 target projects. (2) A qualitative postal survey was sent to 12 people who had played a key role in the development of the Methodology Programme; replies were received from six of them. (3) Analysis was undertaken of the hit rates for 29 projects on the NCCHTA website by the end of February and the end of May 1999, comparing those concerned with methodology (n = 10) and those concerned with other issues (n = 19). RESULTS UNDERTAKING METHODOLOGICAL RESEARCH: VIEWS OF RESEARCHERS: This section summarises the views of 35 researchers who were interviewed by telephone. RESULTS UNDERTAKING METHODOLOGICAL RESEARCH: VIEWS OF RESEARCHERS: (THE NATURE OF METHODOLOGICAL REVIEWS): (1) There was a reluctance among researchers to use the term "systematic review" in the methodological context. (2) Practical problems in undertaking methodological reviews were found at every stage of the research process. (a) In the initial search stage, preplanned strategies were difficult to maintain, owing to the need to respond to the problems of too few or too many references. (b) At the analysis stage, most studies were not formally weighted, but there was implicit weighting in researchers' views of their merits or relevance. (c) It was often only at the synthesis stage that researchers could see clearly what their study was able to do; iteration was frequently necessary at this point. (d) It was difficult to form simple conclusions and recommendations beyond summaries of what was known in the field. (e) Dissemination activities were most often directed to other health service researchers, with some attention to NHS policy makers and research commissioners. RESULTS UNDERTAKING METHODOLOGICAL RESEARCH: VIEWS OF RESEARCHERS (THE NEED FOR FLEXIBILITY): (1) Few researchers had amended their topic or methods once their research was under way, although some had made minor changes to their original plan, generally to refine the topic to fit the time or data available. (2) Changing a topic was seen as inappropriate unless checked with funders, but changes in research methods were viewed as reasonable because questions might be refined in the light of information gained or early thinking. RESULTS UNDERTAKING METHODOLOGICAL RESEARCH: VIEWS OF RESEARCHERS (THE QUESTION OF BIAS): (1) Few researchers considered that this kind of research could be undertaken or presented in a wholly unbiased way because of the need to assess the research studied. (2) Objectivity was nonetheless seen as something that researchers should strive towards. Efforts to do so included presenting data clearly, separating findings from discussion, covering all points of view, setting out their own assumptions and values, and testing their ideas on others known to have differing views. (3) The formal peer-review process was not seen to have made a difference here, primarily because of the stage at which referees become involved. RESULTS UNDERTAKING METHODOLOGICAL RESEARCH: VIEWS OF RESEARCHERS (PROJECT MANAGEMENT--TIMING AND TIME MANAGEMENT): (1) A majority of projects were completed within 3 months of their due date. Those studies completed roughly on time were considered to have efficient junior researchers and good project management, including clear deadlines for different stages of the research. (2) Some studies had severe problems of time management. Too much time tended to be spent on collecting and reading the literature and the writing stage was not always well planned. Referees' comments were also slow in coming. (ABSTRACT TRUNCATED)
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