Showing papers by "Cochrane Collaboration published in 1999"

Problems in the Design and Reporting of Trials of Antifungal Agents Encountered During Meta-analysis

Abstract: Meta-analyses may become biased if the reported data in the individual trials are biased and if overlap among trials cannot be identified. We describe the unanticipated problems we encountered in collecting data for a meta-analysis comparing a new antifungal agent, fluconazole, with amphotericin B in patients with cancer complicated by neutropenia. In 3 large trials that comprised 43% of the patients identified for the meta-analysis, results for amphotericin B were combined with results for nystatin in a "polyene" group. Because nystatin is recognized as an ineffective drug in these circumstances, this approach creates a bias in favor of fluconazole. Furthermore, 79% of the patients were randomized to receive oral amphotericin B, which is poorly absorbed and not an established treatment, in contrast to intravenous amphotericin B, which was administered in 4 of 5 placebo-controlled trials, or 86% of patients. It was unclear whether there was overlap among the "polyene" trials, and it is possible that results from single-center trials were included in multicenter trial reports. We were unable to obtain information to clarify these issues from the trial authors or the manufacturer of fluconazole. Two of 11 responding authors replied that the data were with the drug manufacturer and two indicated that they did not have access to their data because of change of affiliation. In the meta-analyses, fluconazole and amphotericin B (mostly given orally) had similar effects (13 trials), whereas nystatin was no better than placebo (3 trials). Since individual trials are rarely conclusive, investigators, institutions, and pharmaceutical companies should provide essential details about their work to ensure that meta-analyses can accurately reflect the studies conducted and that patients will realize maximum benefits from treatments. We recommend that investigators keep copies of their trial data to help facilitate accurate and unbiased meta-analyses.

System and method for website development

Abstract: A system and method for file management is comprised of hierarchical files systems, referred to as “areas.” There are three types of areas: work areas, staging areas, and edition areas. A work area is a modifiable file system, and, in a work area a user can create, edit, and delete files and directories. A staging area is a read-only file system that supports select versioning operations. Various users of work areas can integrate their work by submitting the contents of their work area to the staging area. In the staging area, developers can compare their work and see how their changes fit together. An edition is a read-only file system, and the contents of a staging area are virtually copied into an edition to create a frozen, read-only snapshot of the contents of the staging area. One use of the system and method for file management is as a website development tool.

Timed intercourse versus intra-uterine insemination with or without ovarian hyperstimulation for subfertility in men.

Abstract: Background Although intra-uterine insemination (IUI) is widely used, however its effectiveness remains a matter of debate. Although IUI is less invasive and expensive than IVF or GIFT, it should only be applied if the probability of conception is improved significantly as compared to the natural chance of conceiving. To increase the number of available oocytes at the site of fertilization, controlled ovarian hyperstimulation (COH) can be applied in conjunction with IUI. Uncontrolled studies suggest a beneficial effect of COH in combination with IUI, also when a male factor is present. To be able to draw firm conclusions whether IUI and/or COH improve the probability of conception, several comparisons should be performed in randomized controlled trials (RCTs). Objectives To determine for male subfertility whether intrauterine insemination (IUI) improves the probability of conception compared with timed intercourse and whether the addition of controlled ovarian hyperstimulation influences the results. Search strategy 1. The specialist database of the Cochrane Menstrual Disorders and Subfertility Group. 2. Medline search. 3. Embase search. 4. DDFU search. 5. BIOSIS search. 6. SCIsearch. 7. Manual searching of references mentioned in the obtained studies. 8. Personal communication and write letters to experts (14) in the field. 9. Abstracts of The American Society for Reproductive Medicine and European Society for Human Reproduction and Embryology Meetings. When important information is lacking from the original publications the authors will be contacted. Selection criteria Randomized controlled trials only. Data collection and analysis Independently by the first 2 authors: 1. Trial design characteristics. 2. Baseline characteristics of participants. 3. Types of intervention. 4. Outcomes where pregnancy is the outcome of main interest. Number of multiple pregnancies and number of cycles with ovarian hyperstimulation syndrome (OHSS) are secondary outcomes. Analysis of agreement between the two observers was determined for the following items: inclusion or exclusion of a trial, method of randomization, definition of male subfertility, design of the trial, number of pregnancies and completed cycles. Sensitivity analysis is performed. Main results Seventeen trials fulfilled the selection criteria for this review and were included. Four trials are pending. Crude agreement concerning inclusion or exclusion of trials occurred for 41 of 43 (95%) trials reviewed (kappa 0.90). The included trials comprised 3,662 completed cycles. In natural cycles intrauterine insemination (IUI) significantly improved the probability of conception compared with timed intercourse (TI) (combined odds ratio with 95% confidence intervals: 2.43, 1.54 - 3.83). In cycles with controlled ovarian hyperstimulation (COH) IUI significantly improved the probability of conception also compared with TI (combined odds ratio with 95% confidence intervals: 2.14, 1.30 - 3.51). Despite clinical heterogeneity, these results are based on strong evidence. Intrauterine insemination in cycles with COH improved the probability of conception compared with IUI in natural cycles but significance was not reached (combined odds ratio with 95% confidence intervals: 1.79, 0.98 - 3.25). Comparing IUI in COH-cycles with TI in natural cycles the first treatment modality significantly improved the probability of conception (combined odds ratio with 95% confidence intervals: 6.23, 2.35 - 16.52). Reviewer's conclusions Intra-uterine insemination offers couples with male subfertility benefit over timed intercourse, both in natural cycles and in cycles with COH. In the case of a severe semen defect (with more than 1 million motile sperm after semen preparation and no triple sperm defect) IUI in natural cycles should be the treatment of first choice. The value of COH need to be further investigated in RCTs. Mild ovarian hyperstimulation with gonadotrophins is advised in cases with less sever

Surgical treatments for ingrowing toenails

Abstract: Background Ingrowing toenails are a common condition which, when recurrent and painful, are often treated surgically. Objectives To evaluate the effectiveness of methods of the surgical treatment of ingrowing toenails. Search strategy Electronic database searching (CENTRAL, MEDLINE, EMBASE, CINAHL) followed by investigation of reference lists of the papers identified from the initial search. Selection criteria Any randomised (or quasi-randomised) controlled trial which compares one form of surgical removal of all or part of a toenail due to its impact on the soft tissues to another or others. Studies must have a minimum follow period of six months and aim to permanently remove the troublesome portion of the nail. Data collection and analysis Data extraction was carried out independently by the two reviewers using a pre-derived data extraction form and entered into RevMan. Categorical outcomes were analysed as odds ratios with 95% confidence intervals. Main results Avulsion with phenol versus surgical excision: Phenolisation combined with simple avulsion of a nail is more effective than the use of more invasive excisional surgical procedures to prevent symptomatic recurrence at six months or more (OR 0.44 CI 95% 0.24 - 0.80). Avulsion with phenol versus avulsion without phenol: The addition of phenol, when performing a total or partial nail avulsion dramatically reduces the rate of symptomatic recurrence, (OR 0.07 95% CI 0.04 - 0.12). This is offset by a significant increase in the rate of post-operative infection when phenol is used (OR 5.69 95% CI 1.93 - 16.77). Authors' conclusions The evidence suggests that simple nail avulsion combined with the use of phenol, compared to surgical excisional techniques without the use of phenol, is more effective at preventing symptomatic recurrence of ingrowing toenails. The addition of phenol when simple nail avulsion is performed dramatically decreases symptomatic recurrence, but at the cost of increased post-operative infection.

Searching the right database. A comparison of four databases for psychiatry journals

Abstract: Journal coverage is one factor that affects the retrieval of relevant information from bibliographic databases. The aims of this study were to investigate the coverage of databases for psychiatry journals, and to assess the overlap between databases. Psychiatry journals were identified using Ulrich’s International Periodicals Directory and then analysed to see which bibliographic databases indexed the most journals. A total of 213 abstracting and indexing services were listed as indexing at least one of the 977 psychiatry journals identified. The four most frequently cited databases (PsycLIT, EMBASE, BIOSIS and MEDLINE) indexed 506 (52%) of the psychiatry journals. Of these 506 journals, PsycLIT indexed 367 (73%), EMBASE 337 (67%), BIOSIS 243 (48%) and MEDLINE 236 (47%). Combining the databases with the highest yields (PsycLIT and EMBASE) increased the number of journals indexed to 461 (91%). The four databases combined accounted for 90% of all psychiatry journals found to be indexed by at least one abstracting and indexing service. More than 400 journals were not indexed at all. Variations in the overlap between PsycLIT, EMBASE, BIOSIS and MEDLINE, and the high proportion (35%) of journals indexed in only one of these four databases emphasize the importance of searching more than one or even two databases to ensure optimal coverage of the literature.

Incremental maintenance of summary tables with complex grouping expressions

Abstract: A method, apparatus, and article of manufacture for the incremental maintenance of summary tables with complex grouping expressions where the change (insert/delete/update) of a single row of the base data can affect multiple rows in the summary table. The invention applies the complex grouping expression to the raw delta, yielding a delta stream consisting of multiple (but distinct) grouping combinations. The invention then inserts/deletes/updates delta values into/from the existing summary table so that each grouping combination of the delta stream modifies its corresponding grouping combination in the summary table.

Cube indices for relational database management systems

Abstract: A method, apparatus, and article of manufacture for optimizing database queries using subsumption tests between the query and at least one summary table that comprises a cube index to determine whether an expression in the query can be subsumed in the summary table. The summary table stores at least one materialized view involving at least one GROUP BY operation that computes at least one of the following: (1) a cube, (2) a rollup, (3) a grouping set, and (4) a concatenation of cubes, rollups, grouping sets, and one or more grouping items. When the expression in the query can be subsumed in the summary table, the query is rewritten to use the summary table.

Single-dose dextropropoxyphene, alone and with paracetamol (acetaminophen), for postoperative pain

Abstract: Background Patient surveys have shown that postoperative pain is often not managed well, and there is a need to assess the efficacy and safety of commonly used analgesics as newer treatments become available. Dextropropoxyphene is one example of an opioid analgesic in current use, and is widely prescribed for pain relief in combination with paracetamol under names such as Co-proxamol and Distalgesic. Objectives To determine the analgesic efficacy and adverse effects of single dose oral Dextropropoxyphene alone and in combination with paracetamol (acetaminophen) for moderate to severe postoperative pain. Search strategy Published reports were identified from: Medline (1966 - November 1996), Biological Abstracts (1985 - 1996), Embase (1980 - 1996), the Cochrane Library (Issue 4 1996), and the Oxford Pain Relief Database (1954 - 1994). Additional studies were identified from the reference lists of retrieved reports. Date of the most recent searches: July 1998. Selection criteria The inclusion criteria used were: full journal publication, postoperative pain, postoperative oral administration, adult patients, baseline pain of moderate to severe intensity, double-blind design, and random allocation to treatment groups which included dextropropoxyphene and placebo or a combination of dextropropoxyphene plus paracetamol and placebo. Data collection and analysis Data were extracted by two independent reviewers, and trials were quality scored. Summed pain intensity and pain relief data were extracted and converted into dichotomous information to yield the number of patients with at least 50% pain relief. This was used to calculate the relative benefit and number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief. Main results Six trials (440 patients) compared dextropropoxyphene with placebo and five (963 patients) compared dextropropoxyphene plus paracetamol 650 mg with placebo. For a single dose of dextropropoxyphene 65 mg in postoperative pain the NNT for at least 50% pain relief was 7.7 (95% confidence interval 4.6 to 22) when compared with placebo over 4-6 hours. For the equivalent dose of dextropropoxyphene combined with paracetamol 650 mg the NNT was 4.4 (3.5 to 5.6) when compared with placebo. These results were compared with those for other analgesics obtained from equivalent systematic reviews. Pooled data showed increased incidence of central nervous system adverse effects for dextropropoxyphene plus paracetamol compared with placebo. Reviewer's conclusions The combination of dextropropoxyphene 65 mg with paracetamol 650 mg shows similar efficacy to tramadol 100 mg for single dose studies in postoperative pain but with a lower incidence of adverse effects. The same dose of paracetamol combined with 60 mg codeine appears more effective but, with the slight overlap in the 95% confidence intervals, this conclusion is not robust. Adverse effects of both combinations were similar. Ibuprofen 400 mg has a lower (better) NNT than both dextropropoxyphene 65 mg plus paracetamol 650 mg and tramadol 100 mg.

Single dose oral aspirin for acute pain.

Abstract: Background Aspirin has been known to be an effective analgesic for many years and is commonly used throughout the world for many different pain conditions. It is important for both prescribers and patients to have the best possible information about the efficacy and safety of analgesics, and this need is reflected in patient surveys which show that postoperative pain is often poorly managed. We also need to benchmark relative efficacy and safety of current analgesics so that we can compare them with new analgesics. Objectives To quantitatively assess the analgesic efficacy and adverse effects of a single-dose of aspirin in acute pain of moderate to severe intensity. Search strategy Randomised trials were identified by searching Medline (1966 to March 1998), Embase (1980 to January 1998), the Cochrane Library (Issue 1,1998) and the Oxford Pain Relief Database (1950 to 1994). Selection criteria The inclusion criteria used were: full journal publication, postoperative pain or a mixture of postoperative and acute trauma pain, oral administration, adult patients, baseline pain of moderate to severe intensity, double-blind design, and random allocation to treatment groups which compared aspirin with placebo. Data collection and analysis Summed pain relief or pain intensity difference over four to six hours was extracted, and converted into dichotomous information yielding the number of patients with at least 50% pain relief. This was then used to calculate the relative benefit and the number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief. Main results Seventy-two randomised single-dose trials met our inclusion criteria, with 3253 patients given aspirin, and 3297 placebo. Significant benefit of aspirin over placebo was shown for aspirin 600/650 mg, 1000 mg and 1200 mg, NNTs for at least 50% pain relief of 4.4 (4.0 to 4.9), 4.0 (3.2 to 5.4) and 2.4 (1.9 to 3.2) respectively. Single-dose aspirin 600/650 mg produced significantly more drowsiness and gastric irritation than placebo, with a number-needed-to-harm (NNH) of 28 (19 to 52) and 38 (22 to 174) respectively. Type of pain model, pain measurement, sample size, quality of study design, and study duration had no significant impact on the results. Reviewer's conclusions Aspirin is an effective analgesic for acute pain of moderate to severe intensity with a clear dose-response. Drowsiness and gastric irritation were seen as significant adverse effects even though the studies were single-dose. The pain relief achieved with aspirin was very similar milligram for milligram to that seen with paracetamol.

Single dose dextropropoxyphene, alone and with paracetamol (acetaminophen), for postoperative pain.

Abstract: Background Patient surveys have shown that postoperative pain is often not managed well, and there is a need to assess the efficacy and safety of commonly used analgesics as newer treatments become available. Dextropropoxyphene is one example of an opioid analgesic in current use, and is widely prescribed for pain relief in combination with paracetamol under names such as Co-proxamol and Distalgesic. Objectives To determine the analgesic efficacy and adverse effects of single dose oral Dextropropoxyphene alone and in combination with paracetamol (acetaminophen) for moderate to severe postoperative pain. Search strategy Published reports were identified from: Medline (1966 - November 1996), Biological Abstracts (1985 - 1996), Embase (1980 - 1996), the Cochrane Library (Issue 4 1996), and the Oxford Pain Relief Database (1954 - 1994). Additional studies were identified from the reference lists of retrieved reports. Date of the most recent searches: July 1998. Selection criteria The inclusion criteria used were: full journal publication, postoperative pain, postoperative oral administration, adult patients, baseline pain of moderate to severe intensity, double-blind design, and random allocation to treatment groups which included dextropropoxyphene and placebo or a combination of dextropropoxyphene plus paracetamol and placebo. Data collection and analysis Data were extracted by two independent reviewers, and trials were quality scored. Summed pain intensity and pain relief data were extracted and converted into dichotomous information to yield the number of patients with at least 50% pain relief. This was used to calculate the relative benefit and number-needed-to-treat (NNT) for one patient to achieve at least 50% pain relief. Main results Six trials (440 patients) compared dextropropoxyphene with placebo and five (963 patients) compared dextropropoxyphene plus paracetamol 650 mg with placebo. For a single dose of dextropropoxyphene 65 mg in postoperative pain the NNT for at least 50% pain relief was 7.7 (95% confidence interval 4.6 to 22) when compared with placebo over 4-6 hours. For the equivalent dose of dextropropoxyphene combined with paracetamol 650 mg the NNT was 4.4 (3.5 to 5.6) when compared with placebo. These results were compared with those for other analgesics obtained from equivalent systematic reviews. Pooled data showed increased incidence of central nervous system adverse effects for dextropropoxyphene plus paracetamol compared with placebo. Reviewer's conclusions The combination of dextropropoxyphene 65 mg with paracetamol 650 mg shows similar efficacy to tramadol 100 mg for single dose studies in postoperative pain but with a lower incidence of adverse effects. The same dose of paracetamol combined with 60 mg codeine appears more effective but, with the slight overlap in the 95% confidence intervals, this conclusion is not robust. Adverse effects of both combinations were similar. Ibuprofen 400 mg has a lower (better) NNT than both dextropropoxyphene 65 mg plus paracetamol 650 mg and tramadol 100 mg.

General practitioners' use of evidence databases.

Abstract: To the Editor: We know (from a range of studies in Australia and overseas) that general practitioner (GP) use of any electronically based information to support clinical decision-making is low. It is therefore not surprising that Young and Ward found a relatively low use of the Cochrane Library. I It is also important not to evaluate the efforts of groups such as the Cochrane Collaboration prematurely, or with inappropriate criteria. The Collaboration has rightly focused its initial efforts on establishing a reliable and credible resource for evidence-based healthcare, and has completed over 500 systematic reviews in a short space of time, many of which have had a significant effect on health services around the world. However, its coverage of healthcare interventions is still relatively patchy overall (and is likely to remain so for several years). For a time this will limit its potential usefulness to GPs, who require information across a broad range of healthcare topics. Furthermore, as acknowledged by Van Der Weyden,2 the issue of GP use of information is complex, and is influenced by time and financial constraints, availability of computer hardware and software, external support for information technology infrastructure, and GP attitudes. We suggest that intervention studies and programs targeting the behaviour and structural environment of GPs will be more useful than simple \"uptake\" questionnaires. It may also be helpful to use the knowledge of information needs generated from GP consultations as the starting point for strategies aimed at increasing the uptake of evidence-based medicine. In Australia, we are working with the Department of Social and Preventive Medicine at the University of Queensland on a pilot clinical information service for GPs. We ask a small number of GPs to send us questions that arise during their consultations. We then prepare an evidence-based answer for them which is short but structured in such a way that the source and validity of the answer can be appraised. We use a \"cascade\" of

Providing evidence-based answers to clinical questions. A pilot information service for general practitioners.

Abstract: Objective: To pilot a clinical information service for general practitioners. Methods: A representative sample of 31 GPs was invited to submit clinical questions to a local academic department of general practice. Their views on the service and the usefulness of the information were obtained by telephone interview. Results: Over one month, nine GPs (29% of the sample, 45% of those stating an interest), submitted 20 enquiries comprising 45 discrete clinical questions. The median time to search for evidence, appraise it and write answers to each enquiry was 2.5 hours (range, 1.0-7.4 hours). The median interval between receipt of questions and dispatch of answers was 3 clays (range, 1-12 days). Conclusions: The GPs found the answers useful in clinical decision making; in four out of 20 cases patient management was altered.

What is evidence-based medicine?

Abstract: Introduction: Three challenges that physicians and decision makers in the health care systems have to meet are a remarkable proportion of medical decisions without a sufficient base of scientific evidence, a slow and opaque process of integrating scientific knowledge into medical practice and a steadily decreasing half-life period of the medical knowledge. Discussion: During the last two decades, a number of projects have faced these problems and forced the development of evidence-based medicine (EBM). This concept claims the explicit conscientious use of current evidence from clinical research combined with the personal expertise in the process of medical decision making. The following article explains the main steps of practising and teaching EBM illustrated by a clinical example.

Relation between experimental and non-experimental study designs. HB vaccines: a case study.

Abstract: STUDY OBJECTIVE: To examine the relation between experimental and non- experimental study design in vaccinology. DESIGN: Assessment of each study design's capability of testing four aspects of vaccine performance, namely immunogenicity (the capacity to stimulate the immune system), duration of immunity conferred, incidence and seriousness of side effects, and number of infections prevented by vaccination. SETTING: Experimental and non-experimental studies on hepatitis B (HB) vaccines in the Cochrane Vaccines Field Database. RESULTS: Experimental and non-experimental vaccine study designs are frequently complementary but some aspects of vaccine quality can only be assessed by one of the types of study. More work needs to be done on the relation between study quality and its significance in terms of effect size.

Fossorial rodent control compositions and methods

Abstract: A method and composition for controlling fossorial rodents are disclosed. The composition is a mixture of water, a foaming agent and a respiratory irritant. The respiratory irritant is preferably finely ground white mustard seeds. The mixture is aerated through a nozzle and pumped into the rodent burrow to exterminate the resident rodent.

Apparatus for processing large square hay bales into smaller recompressed bales

Abstract: An apparatus is provided for processing large hay bales of approximately 750 kg to produce smaller recompacted manageable units to facilitate shipping in containers. The apparatus provides means for cutting the bales into at least two slabs, preferably three slabs, and means for cutting those slabs into two approximately equal pieces. Means are provided for each piece to be recompressed, strapped and cut again to provide units having an approximate weight of 35 kg.

[The identification and description of clinical trials published in Spanish journals of general and internal medicine during the period of 1971-1995].

Abstract: BACKGROUND When faced with a therapeutic issue, the practice of evidence-based medicine requires efficient access to information derived from controlled clinical trials. The objectives of the study were to locate, with the greatest possible exhaustivity, all controlled clinical trials published in Spanish journals of general medicine, between 1971 and 1995 (25 years), to characterize them, and to incorporate them into the worldwide database of clinical trials maintained by the Cochrane Collaboration. METHODS The controlled clinical trials have been identified by a systematic, manual review of all the Spanish journals of general and internal medicine. The results obtained have been compared with an exclusive electronic search in MEDLINE. A descriptive analysis of the characteristics of the localized controlled clinical trials was done. RESULTS 68 journals of general and internal medicine have been identified, only 6 being indexed in MEDLINE. A search carried out exclusively using MEDLINE would imply the loss of one third of all controlled clinical trials. About 16 controlled clinical trials per year have been published in Spain in the area of general and internal medicine, most of them with important missing information. CONCLUSIONS The limitations of searching only in MEDLINE have been shown once again. There are few controlled clinical trials published in Spain in the area of general and internal medicine, and in order to improve their quality and their diffusion is recommended that authors and editors adhered to the international consensus initiatives that are under way.

Abstracts of trials presented at the Vth World Congress of Psychiatry (Mexico, 1971): a cohort study.

Abstract: Background. Systematic reviews should identify all relevant trials in order to minimize the potential for bias and the play of chance in their results. Other specialities have shown that conference proceedings are a rich source of trials, but many of these trials are never fully published. Methods. All clinical trials presented at a single conference (Vth World Congress of Psychiatry, Mexico, 1971) were identified by hand searching. Full publications of these abstracts were then sought on five databases by searching for the authors or relevant key words. Results. Full publications were found for 46% of the abstracts. The odds of publication decreased for abstracts that were from a non-Anglophone country or that failed to mention randomization. Conclusions. Anyone wishing to undertake a systematic review of a mental-health care topic should search relevant conference proceedings for trials.

Evidence-based nephrology.

Abstract: Systematic reviews and meta-analyses are the best approaches available for summarizing the available evidence concerning the efficacy of therapies. Although the renal field has been slow to use these techniques, they are being used increasingly. In March 1997, the Cochrane Renal Group was formed, and this group aims to produce and maintain up to date systematic reviews of the evidence on the effectiveness of therapies used to treat patients with renal diseases. This group is part of the Cochrane Collaboration which is an international structure grouping collaborators together, with the aim of preparing, maintaining and disseminating systematic reviews of the effects of health care in all areas of medicine.

The practice of systematic reviews. I. Introduction

Abstract: A systematic review of the results of randomized, controlled trials employs explicit, systematic methods to produce unbiased and precise estimates of the effect of a treatment on outcomes of clinical importance. The results of such systematic reviews are of importance in that they inform providers and consumers about the effect of treatments and identify priorities for new research. The Cochrane Collaboration is a systematic programme to try to harness this valuable information. An overview of the actual status of systematic reviews of health care interventions is given and a miniseries of papers on systematic reviews is introduced.

Cochrane reviews and systematic reviews of economic evaluations : amantadine and rimantadine in the prevention and treatment of influenza

Abstract: Cochrane reviews provide standardised and regularly updated syntheses of evidence on the effects of healthcare interventions. We present the rationale for, and some of the results of, a Cochrane review of the effects of amantadine and rimantadine in the prevention and treatment of influenza. The estimates of effect will be incorporated into a decision-making model for tackling influenza in healthy adults (i.e. soldiers in the British Army). Our systematic review of the economics of influenza also provides the international context within which economic data can be interpreted and assessed as a preliminary to an economic evaluation comparing alternative prevention and treatment strategies. Systematic reviews provide powerful and relatively inexpensive evidence of effects and tolerability, which is more likely to convince decision-makers than evidence from single studies. Additionally, they can be used to focus clinical trial questions and provide strategic insight regarding the state-of-the-art knowledge of effects and economics of compounds in a specific field.

Assessing the potential cost effectiveness of pneumococcal vaccines in the US: methodological issues and current evidence.

Abstract: Pneumococcal disease imposes a notable burden on society, particularly in the elderly and those at high risk of complications. Preventive strategies, especially vaccines, are possibly the best way to minimise such a burden. We report on the conduct and results of a preliminary exploratory review of the economics of pneumococcal vaccines in the elderly population in the US. After extensive electronic and manual searches, we identified 5 economic evaluations that fulfilled our study criteria. From these we extracted key economic variables and assessed the quality of the studies against the criteria in the checklist for authors and peer reviewers of economic submissions to the British Medical Journal. We found variation of quality of study design such as a lack of clarity in the treatment of indirect costs and a failure to present the data on resource use and costs separately. We carried out supplementary searches to assess the quality of the epidemiological and efficacy evidence upon which the economic models were based and found contradictory evidence of effects of the vaccines, which included the results of 2 meta-analyses. One of these meta-analyses reported that retrospective studies, especially case-control studies, tended to underestimate the protective efficacy of the vaccine by as much as 20%. We believe that a well resourced Cochrane review of the clinical evidence of the effects of the vaccines should be carried out before any further economic studies. No more economic modelling should take place before such a review is undertaken.

Are African governments allocating sufficient resources to fight AIDS

Abstract: EDITOR—The editorial by Wilkinson et al addresses the important question of programmes to prevent perinatal transmission of HIV in Africa.1 The authors highlight the prohibitive cost of zidovudine and suggest that placebo controlled trials should be revived. Since the prevalence of HIV infection among pregnant women is above 30% in some parts of South Africa (A Smith, HIV-AIDS update symposium, Durban, Natal, South Africa, January 1999), AIDS is now the biggest threat to African society. …