Salmeterol for nocturnal asthma.
Explore the source record for details and available documents.
Adolescent↗
Biomedical subjects
S Bryan
Publications and source records attributed to S Bryan.
Examining the influence of picture archiving communication systems and other factors upon the length of stay for patients with total hip and total knee replacements.
OBJECTIVES: To examine the influence of a picture archiving and communication system (PACS) on the length of stay (LOS) for patients receiving total hip replacement (THR) or total knee replacement (TKR) procedures. METHODS: A before-and-after design was used. Data were collected on all THR and TKR procedures at Hammersmith Hospital from 1993-96. A regression approach was used to examine the influence of PACS on LOS. Factors such as patient age, sex, and physician were controlled for. RESULTS: Type of admission and discharge, month of procedure, complications, and number of procedures all significantly influenced LOS for patients undergoing THR. For patients receiving TKR, age, sex, admission, prosthetic complications, number of procedures, and PACS significantly influenced LOS. CONCLUSIONS: While this study shows an apparent reduction of 25% in the average LOS for TKR patients at the time PACS was introduced, this is unlikely to be a true PACS effect and no similar reduction in LOS was shown for THR patients.
Aged↗
Magnetic resonance imaging for the investigation of knee injuries: an investigation of preferences.
The conventional approach to the diagnosis and treatment of severe knee injuries is arthroscopy, a minimally invasive surgical procedure. Since arthroscopy is an invasive technique that carries risks, magnetic resonance imaging (MRI) is increasingly being used for diagnosis. MRI is potentially associated with diagnostic and therapeutic 'impacts', in that arthroscopy can be avoided. This paper reports a discrete choice conjoint analysis exercise that assessed the value placed on such 'impacts' by potential patients and investigated the degree to which respondents were willing to trade between process and outcome. The marginal rates of substitution between attributes were estimated. The results suggest that the diagnostic and therapeutic 'impacts' of MRI were valued by many respondents. The study has highlighted a number of important issues for the design and analysis of future health-related conjoint studies, including the use of treatment cost as an attribute, dealing with data from lexicographic respondents, and distinguishing between points of indifference and missing data.
Adult↗
Health-related quality of life following liver transplantation.
The objectives of this study were to report on the health-related quality of life (QoL) experienced by patients following liver transplantation and to investigate the factors associated with its variation. A questionnaire comprising the SF-36 and EuroQol EQ-5D instruments was sent by post to 147 patients who had received a liver transplant, indicated by a chronic liver disease, in the previous 8 years. The scores of the respondents were compared to population norm scores. The variation in both the SF-36 and EQ-5D scores was explored. Many liver transplant patients experienced most satisfactory QoL levels post-transplantation although, in general terms, the levels were poorer than those seen in the general population. The variation in the post-transplant health-related QoL scores was found to be associated with a number of pre-transplant factors: disease severity (proxied by Child Pugh class), disease duration at the time of transplantation and liver transplant history (whether the patient had received a single or multiple transplants). In making clinical decisions about the use of transplantation for chronic liver diseases, consideration should be given to the key factors likely to affect subsequent health-related QoL.
Adolescent↗
Humoral immunity to commensal oral bacteria in human infants: salivary antibodies reactive with Actinomyces naeslundii genospecies 1 and 2 during colonization.
The secretory immune response in saliva to colonization by Actinomyces naeslundii genospecies 1 and 2 was studied in 10 human infants from birth to 2 years of age. Actinomyces species were not recovered from the mouths of the infants until approximately 4 months after the eruption of teeth. However, low levels of secretory immunoglobulin A1 (SIgA1) and SIgA2 antibodies reactive with whole cells of A. naeslundii genospecies 1 and 2 were detected within the first month after birth. Although there was a fivefold increase in the concentration of SIgA between birth and age 2 years, there were no differences between the concentrations of SIgA1 and SIgA2 antibodies reactive with A. naeslundii genospecies 1 and 2 over this period. When the concentrations of SIgA1 and SIgA2 antibodies reactive with whole cells of A. naeslundii genospecies 1 and 2 were normalized to the concentrations of SIgA1 and SIgA2 in saliva, the A. naeslundii genospecies 1- and 2-reactive SIgA1 and SIgA2 antibodies showed a significant decrease from birth to 2 years of age. The fine specificities of A. naeslundii genospecies 1- and 2-reactive SIgA1 and SIgA2 antibodies were examined by Western blotting of envelope proteins. Similarities in the molecular masses of proteins recognized by SIgA1 and SIgA2 antibodies, both within and between subjects over time, were examined by cluster analysis and showed considerable variability. Taken overall, our data suggest that among the mechanisms Actinomyces species employ to persist in the oral cavity are the induction of a limited immune response and clonal replacement with strains differing in their antigen profiles.
Actinomyces↗
Extrapolation of cost-effectiveness information to local settings.
Providers and purchasers of health care are increasingly looking to the results of economic evaluations for guidance when making their decisions. In this paper the authors argue that there are dangers involved in the naive and unthinking use of published cost-effectiveness information outside the setting in which the information was generated. In considering whether the results of a published study are likely to be relevant locally, decision-makers are encouraged to assess whether the values of the key parameters reported in the published study apply locally. The possible sources of variation are described: unit cost differences; differences in the prevalence, incidence or natural history of disease; and differences in the comparators. In situations where the only source of variation is that local unit costs are different, local values can be substituted in the published analysis and local cost-effectiveness results estimated. Where the other sources of variation exist, the decision-maker is required to make an assumption about the nature of the interaction between the sources of variation and the values of the cost-effectiveness parameters. Using an example, the authors argue that local threshold analysis can aid decision-making where the policy change being considered has a high probability either of increasing effectiveness or reducing costs. Without local re-analysis, there is a danger that local policy changes in line with the recommendations of published studies will promote inefficiency. Re-analysis in the local setting is, however, reliant on authors of economic evaluations being explicit about their methods and the comparators used in their analyses.
Cost-Benefit Analysis↗
Radiology report times: impact of picture archiving and communication systems.
OBJECTIVE: We investigated the impact on radiologist reporting time of the change from conventional film to hard-copy computerized radiography and of the subsequent move to soft-copy images on picture archiving and communication system (PACS) workstations. MATERIALS AND METHODS: A controlled before and after research design was undertaken. Data were collected on four occasions: two relating to conventional film, one relating to hard-copy computerized radiography, and one relating to soft-copy PACS images. Data collection was by direct observation of radiology reporting sessions by independent health service researchers. Data were collected on report times, details of images viewed, characteristics of the radiologist, and details of interruptions. To control for potential biases in the before and after comparisons, ordinary least squares multiple regression analysis was used. The principal comparison was between reports with PACS and reports with computerized radiography hard-copy because no change was noted in the organization of the reporting process between these two data collection rounds other than the introduction of the PACS. RESULTS: Data were collected on a total of 5568 report observations. Report time in the PACS data collection period was not significantly different (p = .32) than that in the computerized radiography hard-copy period. Reporting with the PACS was associated with significantly more (p < .01) historical images (i.e., images of the same patient obtained in previous examinations) being viewed. CONCLUSION: Report time was not lengthened by the introduction of the PACS. The finding that more historical images were viewed when the PACS was in use indicates that the PACS brought about a positive change in reporting practice.
Bias↗
The 1997 NASN research award winner. School nurses' perceptions of their interactions with nurse practitioners.
Relationships between traditional school nurses and nurse practitioners were studied using a descriptive research design. The study analyzed school nurses' perceptions of their professional interactions with nurse practitioners. A researcher-developed questionnaire was sent to 500 Missouri school nurses living in zip-code areas known to employ a high concentration of nurse practitioners. Of the 295 school nurses who responded, 148 had interacted professionally with a nurse practitioner in the previous 5 years. Analysis of the responses indicated an overall positive regard for the nurse practitioner role. Data from this study will be used to support and further improve working relationships between these two nursing specialty groups.
Attitude of Health Personnel↗
Clinical economics review: cost-effectiveness in the therapy of liver disease.
There have been many advances made in the management of patients with liver disease both in diagnosis and in the treatment of underlying liver disease and its complications, although comparatively few of these have been rigorously subjected to full cost-effectiveness evaluation. In this review, we have analysed a small number of the therapeutic interventions; while these have been well evaluated clinically, very few have been analysed from the viewpoint of cost-effectiveness and, thus, it is difficult to make many definitive claims. It is hoped that future studies will consider these aspects as well.
Ascites↗
Mammography screening: an incremental cost effectiveness analysis of double versus single reading of mammograms.
OBJECTIVE: To compare mammography reading by one radiologist with independent reading by two radiologists. DESIGN: An observational non-randomised trial at St Margaret's Hospital, Epping. SUBJECTS: 33 734 consecutive attenders for breast screening in the main trial and a sample of 132 attenders for assessment who provided data on private costs. INTERVENTIONS: Three reporting policies were compared: single reading, consensus double reading, and non-consensus double reading. MAIN OUTCOME MEASURES: Numbers of cancers detected, recall rates, screening and assessment costs, and cost effectiveness ratios. RESULTS: A policy of double reading followed by consensus detected an additional nine cancers per 10 000 women screened (95% confidence interval 5 to 13) compared with single reading. A non-consensus double reading policy detected an additional 10 cancers per 10 000 women screened (95% confidence interval 6 to 14). The difference in numbers of cancers detected between the consensus and non-consensus double reading policies was not significant (95% confidence interval -0.2 to 2.2). The proportion of women recalled for assessment after consensus double reading was significantly lower than after single reading (difference 2.7%; 95% confidence interval 2.4% to 3.0%). The recall rate with the non-consensus policy was significantly higher than with single reading (difference 3.0%; 2.5% to 3.5%). Consensus double reading cost less than single reading (saving 4853 pounds per 10 000 women screened). Non-consensus double reading cost more than single reading (difference 19 259 pounds per 10 000 women screened). CONCLUSIONS: In the screening unit studied a consensus double reading policy was more effective and less costly than a single reading policy.
Breast Neoplasms↗
Issues in the evaluation of picture archiving and communication systems.
Picture archiving and communication systems (PACS) are an example of the application of computer technology in the medical field. PACS automates image handling in a hospital and has the potential to transform the way radiology is currently performed. This paper focuses on the evaluation of the PACS technology, and considers the claims that have been made for PACS, how these claims might be turned into questions to be addressed by evaluation and the appropriate methods for the evaluation of PACS. A distinction is drawn between evaluation questions for which the hospital is the appropriate focus and those for which the patient is the appropriate focus. The preferred research design is different for hospital focused PACS evaluation and patient-focused evaluation of small scale PACS systems. A contemporaneous experimental comparison within hospitals is the preferred design for the patient-focused evaluation of small scale PACS systems. The patient-focused evaluation of large scale systems and the hospital-focused evaluation of all PACS systems could feasibly be conducted as contemporaneous experimental comparisons between hospitals but the large research costs implied by such a design almost certainly mean that non-contemporaneous, non-experimental comparisons within hospitals are more realistic. The current situation for the PACS technology is that it has potential, but as yet unproven, benefits and a large capital cost. Thus, the primary purpose of funding additional PACS implementations must be to add to the currently small body of evaluation evidence.
Cost Savings↗
Evaluation of diffuse technologies: the case of digital imaging networks.
There have been significant developments in recent years in the methodologies and methods for the evaluation of a wide range of health technologies. There remain, though, many technologies which are difficult to evaluate. Often the difficulty stems from the complexity of the technologies themselves, which are in effect hybrids, comprising combinations of several distinct elements. In this paper these are termed 'diffuse' technologies, because the different elements exert different costs and effects, often across several different services. Computer networks are one, increasingly important, example of such technologies in health care. While it is possible to evaluate individual elements of such technologies, it is not clear how to evaluate the technology as a whole, where the whole may be greater (or less) than the sum of the parts. The paper outlines a seven-stage framework for the evaluation of diffuse technologies. The general principles of evaluation are illustrated using the example of picture archiving and communication systems (PACS), which are computer systems designed to capture, store and distribute electronic radiological images within a hospital.
Cost-Benefit Analysis↗
Mammography screening: an incremental cost effectiveness analysis of two view versus one view procedures in London.
STUDY OBJECTIVE: To compare the costs and effects of routine mammography screening by a single mediolateral-oblique view and two views (mediolateral-oblique plus craniocaudal) of each breast. DESIGN: A cost effectiveness analysis of a prospective non-randomised trial comparing one and two view mammography screening was carried out at St Margaret's Hospital, Epping. All women in the study had two view mammography. The mediolateral-oblique view was always the first image read by the radiologist. After reading the films for a clinic session, the same radiologist then went back and read both the mediolateral-oblique and craniocaudal views together. Each set of films was read by two radiologists. The main outcome measures were recall rates, number of cancers detected, screening and assessment costs, and cost effectiveness ratios. SUBJECTS: A total of 26,430 women who attended for breast screening using both one and two view mammography participated. A sample of 132 women attending for assessment provided data on the private costs incurred in attending for assessment. RESULTS: There was a reduction in the recall rate from 9.1% (2404 of 26,430) after one view screening to 6.7% (1760 of 26,430) after two view screening. The results also suggest that for every 10,000 women screened an additional five cancers would be detected earlier with two view screening. The additional health service screening cost associated with two view screening was estimated to be 3.63 pounds: the costs associated with one and two view screening policies were estimated to be 41.49 pounds and 32.99 pounds respectively. Private costs incurred were estimated to be 0.35 pounds per woman screened and 32.75 pounds per woman assessed. Two cost effectiveness ratios were calculated: an incremental health service cost per additional cancer detected of 4129 pounds and an incremental health service plus private cost per additional cancer detected of 2742 pounds. The sensitivity analysis suggested that the results were sensitive to relatively large changes in a number of parameters. These included screening costs, assessment costs, equipment life, and recall rates. CONCLUSIONS: Use of two view screening increased early cancer detection and also costs. The reduction in the recall rate with two views was not sufficiently large to make the cost of two view screening neutral. While these results are not completely generalisable, a framework is provided to allow other centres to estimate the cost effectiveness of two view screening in their locality.
Breast Neoplasms↗
Private costs associated with abdominal aortic aneurysm screening: the importance of private travel and time costs.
OBJECTIVES: To assess the importance of the private costs incurred by patients when making a judgment on the economics of screening for abdominal aortic aneurysm (AAA), and to explore the variation in such costs depending on screening location. SETTING: A district general hospital and general practitioner surgeries. METHODS: Four hundred and ninety nine consecutive subjects attending for AAA screening completed a questionnaire asking about travel arrangements for the journey to and from the clinic, the distance travelled, the time taken, the mode of transport, and any out-of-pocket expenses incurred. In addition, at the clinic each subject was asked what activities they had forgone in attending the clinic. Time was valued differently depending on whether work or leisure activities were forgone. The total private cost for each attender was calculated and comparison was made between attenders at hospital and at general practice. RESULTS: A significantly greater proportion of subjects were accompanied when attending hospital than when attending general practitioner (GP) surgeries. Most attenders travelled by car, but the journey time was significantly longer for those visiting hospital. The expected total private cost associated with attendance for AAA screening was 5.47 pounds. Attendance at GP surgeries had a lower private cost (4.21 pounds) than attendance at hospital (6.87 pounds). Only 7.3% of all men surveyed, and 6.5% of all companions, would have been taking part in some form of paid occupation if they had not attended for screening. CONCLUSION: Despite the fact that most attenders for AAA screening will be retired, the associated private costs are appreciable and should be considered in assessing the economics of such screening programmes. The level of private costs varied depending on the location of screening; clinics held at GP practices had lower private costs than those held at hospital.
Aged↗
Explaining variation in radiologists' reporting times.
This paper describes an investigation into the reasons for variation in the time taken by senior radiologists to complete radiological reports. An observational study of the reporting process at one UK hospital was undertaken for a 25 day period. An independent health service researcher observed the radiology reporting process and collected data on a variety of factors including the time taken to produce the report, the number and nature of all images viewed, the experience of the radiologist, and the number of disturbances that occurred. The nature of the variation in reporting time was explored using both simple comparative statistics and more sophisticated multiple regression techniques. Data were collected on 2345 report observations and the median report time was 117 s. This research provides the first empirical evidence for systematic variation in reporting time. The results confirm the importance of certain factors that were expected to explain report time variation. For example, the results indicate that report time tended to be significantly shorter in reporting sessions that were busy, and significantly longer when the radiologist was disturbed during the reporting process or was training juniors during a reporting session. More surprising were the results indicating that there was no significant difference in report time for reports categorized as urgent or "hot" and those categorized as less urgent or "cold", and that report time appeared to vary systematically depending on the day of the week and on the time of day.
Humans↗
Variations in the incidence, management and outcome of stroke in residents under the age of 75 in two health districts of southern England.
BACKGROUND: The aim of the study was to determine the incidence, outcome and health service resources consumed by stroke care in defined populations. METHODS: Patients under the age of 75 experiencing their first stroke between August 1989 and July 1991 were assessed at the onset, and at three and 12 months after their stroke. The settings were West Lambeth (WL) and Tunbridge Wells (TW) health authorities in southern England. The main outcome measures used were: age- and sex-specific incidence rates, hospital admission rates, length of stay and use of rehabilitation services. Functional disability was assessed using the Barthel scale. RESULTS: Four hundred and fifty-six strokes were registered. The annual incidence rates/1000 population aged under 75 years old [with 95% confidence interval (CI)] were 0.77 (0.67-0.87) in WL and 0.66 (0.58-0.75) in TW. The age- and sex-standardized incidence ratios were significantly higher in WL (126; 95% CI 110-144) than in TW (84%; 95% CI 74-95) (p < 0.001). There were independent associations of incidence with age group (p < 0.001), sex (p < 0.001) and ethnic group (p < 0.001). One year case-fatality was 36% (80/225). At one year, 11% (14) of surviving patients were moderately to severely disabled and 23% (28) mildly disabled. Seventy-one percent (326) of patients were admitted to hospital and the average health service cost per case was pound 3800 in WL and pound 2650 in TW, 93% of the cost being for in-patient care. CONCLUSION: The study has demonstrated a significantly increased incidence of stroke in an inner-city district compared with a district in rural southern England. It has also established ethnic group as a significant independent risk factor for stroke in the United Kingdom. The cost of care to the health services is considerable, and largely reflects nursing costs in hospital rather than effective treatment packages for stroke.
Adult↗