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PubMed2000

Psychotherapy for bulimia nervosa and binging.

OBJECTIVES: The review aims to evaluate the psychotherapeutic treatments for those with binge eating syndromes, that have been tested in randomised controlled trials. Specifically, cognitive-behavioural(CBT) therapy is compared with waiting list or a non-treatment group, any other psychotherapy, CBT in a "pure self-help" form and CBT augmented by exposure and response therapy. As well, the reveiw aims to evaluate the evidence for the efficacy of other psychotherapies when compared to a no treatment control group and to evaluate the evidence for the efficacy of other psychotherapies when compared to a 'placebo' therapy. SEARCH STRATEGY: Handsearch of The International Journal of Eating Disorders since its first issue; database searches of MEDLINE, EXTRAMED, EMBASE, PSYCHLIT, CURRENT CONTENTS, LILACS, SCISEARCH, The Cochrane Collaboration Controlled Trials Register and the Cochrane Depression, Anxiety and Neurosis Group Database of Trials; citation list searching and personal approaches to authors communication are used. SELECTION CRITERIA: All studies that have tested any form of psychotherapy for adult patients with non-purging bulimia nervosa, binge eating disorder and/or EDNOS of a bulimic type, and which have applied a randomised controlled and standardized outcome methodology, are sought for the purpose of this review. DATA COLLECTION AND ANALYSIS: Data are entered into a spreadsheet programme, and into the REVMAN analysis program. Relative risk analyses are conducted of binary outcome data. The relative risk analysis is used rather than the odds ratio as the outcome measures proposed are not measuring a rare event (such as death) and the total number of studies is small. Standardized mean difference analyses are conducted of continuous variable outcome data, as the continuous outcome measures are not consistent across studies. Sensitivity analyses are conducted of a number of measures of trial quality. Data were not reported in such a way to do subgroup analyses, but the effect of treatment on depressive symptoms, psychosocial and/or interpersonal functioning, general psychiatric symptoms and weight is examined where possible. Chi-square tests for homogeneity are done, @ 5% level of significance, using a fixed effects model. Funnel plots to evaluate presence of publication bias are completed and available in a text file upon request. MAIN RESULTS: To date, 1360 trials have been generated by searching and 58 trials have been evaluated in detail. Because of a relatively high number of exclusions (n=12) the trial inclusion criteria were broadened to include those with non-blinded outcome assessment, providing 20 trials for analyses. Because of incomplete published and available data, at best up to 10 studies had data available for any single analysis. The maximum number of total patients included in a single analysis is 396. The majority of studies (18) evaluate patients with bulimia nervosa of a purging type. CBT is superior to waiting list controls with respect to abstinence from binge eating (RR 0.64 CI.53-.78). CBT is not superior to other psychotherapies with respect to abstinence from binge eating (RR.79, CI.54-1.17). CBT in a full or less intensive form is not significantly superior to CBT in a pure self-help form. Augmentation of CBT with exposure therapy is not more effective than CBT alone. NonCBT-psychotherapies also have significantly greater abstinence rates in comparisons with wait-list controls, but there is a paucity of such studies (RR 0.67, CI.56-.81, n=3 studies). Funnel plots suggest a bias towards publication of positive outcome studies only. REVIEWER'S CONCLUSIONS: There is small body of evidence for the efficacy of cognitive-behaviour therapy in bulimia nervosa and similar syndromes, but the quality of trials is very variable (e.g. the majority, 12, are not blinded) and sample sizes are often very small. More trials are needed, particularly for binge eating disorder and other EDNOS syndromes, and evalu

Adult↗

PubMed2000

Hip protectors for preventing hip fractures in the elderly.

BACKGROUND: Hip fracture in the elderly is usually the result of a simple fall and hip protectors have been advocated as a means to reduce impact and consequences of such falls. OBJECTIVES: To determine if external hip protectors reduce the incidence of hip fractures in elderly persons following a fall. SEARCH STRATEGY: The Cochrane Musculoskeletal Injuries Group trials register, MEDLINE, and reference lists of relevant articles were searched, and identified trialists contacted. Date of the most recent search: August 1998. SELECTION CRITERIA: All randomised or quasi-randomised controlled trials comparing the use of hip protectors with a control group. DATA COLLECTION AND ANALYSIS: Two reviewers independently assessed trial quality, using a ten item scale, and extracted data. Additional information was sought from all trialists. Wherever appropriate and possible, the data are presented graphically. MAIN RESULTS: Five randomised trials involving 1681 participants were included within the review. All studies involved elderly people in nursing homes or residential care, three within the Scandinavian countries, one in Japan and one in the United Kingdom. The two largest studies involving 1409 participants randomised by nursing home or nursing home ward rather than by the individual (cluster randomisation). One study of 141 individuals was primarily a compliance study. Summation of results from four of these studies gave an occurrence of hip fractures of 13/620 (2.1%) for those allocated to wear hip protectors, against 57/920 (6.2%) to those not allocated to wear protectors. However due to the large number of participants allocated by cluster randomisation it was not possible to demonstrate conclusively that this difference between groups was statistically significant. Only one of the 13 hip fractures that occurred in the individuals allocated to wear hip protectors occurred whilst the protector was worn. No significant adverse effects of the hip protectors were reported but compliance, particularly in the long term, was poor. REVIEWER'S CONCLUSIONS: Hip protectors appear to reduce the risk of hip fracture within a selected population at high risk of sustaining a hip fracture. However, this conclusion is based on four trials of low to moderate quality. As two used cluster randomisation, pooling of data was not possible. The generalisability of the results is unknown beyond high-risk populations. Results from six ongoing trials may clarify this situation. Acceptability by users of the protectors remains a problem, due to discomfort and practicality.

Aged↗

PubMed2006

Systematic reviews in midwifery.

This paper highlights the key steps to follow when conducting a systematic review (see Box 2). Healthcare practitioners may be limited by time and resources when conducting literature reviews, however, a systematic and transparent approach should be adopted wherever possible. Further detailed guidance on conducting systematic reviews is available from the NHS Centre for Reviews and Dissemination (NHS CRD, 2001) and the Cochrane Reviewers' Handbook (Alderson et al, 2003).

Databases, Bibliographic↗

PubMed2006

Pitfalls in systematic reviews.

PURPOSE OF REVIEW: The term 'evidence-based medicine' means integrating individual clinical expertise with the best available external clinical evidence from systematic research. An important source for those who wish to practise evidence-based medicine is the systematic review. Systematic reviews, however, are not without their pitfalls. This review will consider the problems and challenges for researchers and users of systematic reviews. RECENT FINDINGS: Failure to adequately assess study quality, funding bias, publication bias, reliance on outcomes that provide no help in clinical decision-making, analysis errors and the incorrect use of evidence statements are all common pitfalls in systematic reviews. SUMMARY: There are several steps in completing a systematic review. These include developing the clinical question, searching for all available literature, study selection, assessment of study quality, data extraction, data analysis, interpreting the results, implications for practice and further research, and finally updating the review in a timely manner. Authors of systematic reviews need to be aware of these problems and attempt to address them so that research evidence may be of clinical value to both providers and consumers of healthcare.

Evidence-Based Medicine↗

PubMedDate not supplied

Evidence-based practice.

This article summarises how evidence-based practice is defined, and what might constitute evidence. It describes the steps that should be taken in a systematic review of evidence, and some of the issues involved in implementing the findings of such reviews in practice.

Bias↗

PubMed2001

Systematic reviews: gatekeepers of nursing knowledge.

The past few decades have seen a considerable increase in the number of available health care products and interventions. This growth has been matched by a similar expansion in the health care literature. As a result of these factors, the demand for evidence to support practice is growing, but finding the best evidence is becoming increasingly difficult. In response, the use of systematic reviews is increasing and they are starting to replace the primary research as the basis for health care decisions. To date, these reviews have focused predominantly on effectiveness and so have been limited to randomized controlled trials. As a result of this, the interpretive, observational and descriptive research methods that are utilized by nursing have commonly been either excluded from the review or are classified as 'low level' evidence. To address this, nursing must participate in the development of systematic review methods that better answer the questions posed by the profession.

Attitude of Health Personnel↗

PubMed2002

Methods of meta-analysis: an analysis.

PURPOSE OF REVIEW: To understand the principles of systematic reviewing and meta-analysis, using recent examples from the medical literature to highlight some of these points. RECENT FINDINGS: The word 'meta-analysis' is an intimidating one, and its associated jargon makes it seem incomprehensible. Actually, it is only a mathematical maneuver to add up data in a systematic review; it might be better called 'meta-addition'. The systematic review is a process of using the best available evidence to answer a particular clinical question. Data combination (usually done with meta-analysis) increases the power to see small differences and makes a more precise estimate of a treatment effect. Its major drawback is heterogeneity (the proverbial problem of adding apples and oranges). Systematic reviews have been used by medical societies to create position statements. Such statements have suggested that parenteral nutrition is far less efficacious than previously believed. Systematic reviews in some areas of nutritional support have clarified type II errors. Problems exist, however, in a number of the published meta-analyses of aspects of this therapy. SUMMARY: Especially in an era of resource restraint, we need to become more skilled at interpreting evidence from clinical research.

Clinical Trials as Topic↗

PubMed2001

Counselling for depression in primary care.

BACKGROUND: There is wide clinician and patient support for counselling in primary care, particularly in the UK. This review examines the effectiveness and cost effectiveness of counselling for psychological and psychosocial problems in the primary care setting. OBJECTIVES: To assess the effects of counselling in primary care by reviewing cost and outcome data for patients with psychological and psychosocial problems considered suitable for counselling. SEARCH STRATEGY: The search strategy included electronic searching of databases (including the CCDAN Register of RCTs and CCTs) along with handsearching of a specialist journal. Published and unpublished sources (clinical trials, books, dissertations, agency reports etc.) were searched, and their reference lists scanned. Contact was made with subject experts and CCDAN members. SELECTION CRITERIA: Randomised and controlled patient preference trials comparing counselling in primary care with usual general practitioner care for patients with psychological and psychosocial problems considered suitable for counselling. Trials completed before the end of April 1998 were included in the review. DATA COLLECTION AND ANALYSIS: Trials were independently assessed by at least two reviewers for appropriateness of inclusion and methdological quality. MAIN RESULTS: Four trials, involving 678 participants, of whom 487 were followed up, were included. Data for psychological symptom levels (four trials) were pooled statistically. Patients receiving counselling had significantly better psychological symptom levels post intervention than patients receiving usual general practitioner care (standardised mean difference -0.30, 95% CI, (-0.49 to - 0.11). The effect remained statistically significant when the results from studies with less rigorous methodology were excluded in a sensitivity analysis. Patients who received counselling tended to be more satisfied with their treatment (three trials). Health service utilisation data were reported in all trials reviewed, but only one trial undertook a cost analysis. No clear cost advantage was associated with either counselling or usual general practice care. REVIEWER'S CONCLUSIONS: Patients who received counselling were more likely to have improved psychological symptom levels than those who did not receive counselling. Levels of satisfaction with counselling were high. There is limited information about the cost effectiveness of counselling, with one study reporting no clear cost advantage with either counselling or general practice care. The four trials included in this review were all pragmatic trials of counselling in primary care in the UK, which reflect the reality of clinical provision in this context. There were methdological weaknesses identified in the studies, which should be taken into account when considering the results. The evidence base will be extended by trials of counselling which are nearing completion.

Controlled Clinical Trials as Topic↗

PubMed2005

Essential elements of evidenced-based endodontics: steps involved in conducting clinical research.

Endodontists have the opportunity to apply relevant research findings to the care of their patients using the principles and methods of evidence-based treatment. Finding evidence begins with a specific, well-built clinical question. Once a specific question is framed, the validity and relevance of the evidence need to be appraised. The best levels of evidence can then be used to inform decisions regarding care. The purpose of this paper is to discuss the history of evidence-based treatment and to clarify the process of conducting a systematic review. The various types of research designs appropriate for answering clinical questions most commonly encountered in dental practice, including a description of the strengths and weaknesses of each, are also presented. Finally, the implications of evidence-based research on endodontics and future research are outlined.

Dental Research↗

PubMed2000

Extramedullary fixation implants for extracapsular hip fractures.

BACKGROUND: Extramedullary fixation of hip fractures refers to the application of a plate and screws to the lateral side of the proximal femur. OBJECTIVES: To compare different types of extramedullary fixation implants for the surgical treatment of extracapsular hip fracture in adults. SEARCH STRATEGY: We searched the Cochrane Musculoskeletal Injuries Group trials register and reference lists of relevant articles. Date of the most recent search: March 1998. SELECTION CRITERIA: All randomised or quasi-randomised trials comparing extramedullary implants used in the fixation of extracapsular hip fracture in adults. DATA COLLECTION AND ANALYSIS: All three reviewers independently assessed trial quality, using a ten item scale, and extracted data. Additional information was sought from all trialists. Wherever appropriate and possible, results of outcome measures were pooled by comparison. MAIN RESULTS: The methodological quality of all six included trials was poor and in no trial was there clear concealment of allocation. Three trials involving 355 patients compared a fixed nail plate (Jewett or McLaughlin) with the sliding hip screw (SHS). The limited data presented indicated an increased risk of fixation failure outcomes for fixed nail plates. One trial involving 233 patients compared the RAB plate (a fixed angle blade plate with an oblique connecting strut) with the SHS. In this trial both implants had a high incidence of fixation failure. There was a tendency to a lower incidence of cut-out, re-operation, fixation failure, leg shortening, varus deformity and mortality for the RAB plate. None of the differences in these outcomes were statistically significant. One trial involving 100 patients compared the Pugh nail and the SHS. There was no significant difference between implants for the outcome measures reported. One trial involving 176 patients with 182 fractures, compared the Medoff plate with the SHS. A significantly higher mean operative blood loss and longer mean operative time were reported for the Medoff plate. There was however a tendency to a lower risk of fixation failure for unstable trochanteric fractures fixed with the Medoff plate. REVIEWER'S CONCLUSIONS: The fixed nail plate was demonstrated to have to an increased risk of implant breakage and fixation failure in comparison to the SHS. Although the lack of evidence from randomised trials for other outcomes means that a firm conclusion of overall superiority of the SHS cannot be made, the increased fixation failure rate is a major consideration and indicates that the SHS is preferable. Insufficient information is available to draw firm conclusions of the clinical significance of differences between the SHS and either the RAB plate, the Pugh nail or the Medoff plate.

Bone Plates↗

PubMed2000

Oral misoprostol for induction of labour with a viable fetus.

BACKGROUND: Misoprostol is a synthetic prostaglandin which has been used to induce labour. Oral use of the drug misoprostol may be convenient, but an overdose could cause uterine hyperstimulation and precipitate labour which may be life-threatening for both mother and fetus. OBJECTIVES: The objective of this review was to assess the effects of oral misoprostol used for labour induction in women with a viable fetus. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register. SELECTION CRITERIA: Randomised trials of oral misoprostol versus any other method, placebo or no treatment given to women with a viable fetus for induction of labour. DATA COLLECTION AND ANALYSIS: The selection of trials and data extraction were undertaken by one reviewer and independently checked by two other reviewers. MAIN RESULTS: Five trials were included. In one placebo trial, oral misoprostol reduced the need for oxytocin infusion and shortened delivery time in women with prelabour rupture of membranes at term. In another trial, compared to vaginal prostaglandins, oral misoprostol reduced the need for oxytocin (relative risk 0.62, 95% confidence interval 0.47 to 0.82). Based on two trials, the caesarean section rate with oral misoprostol was 20. 2% (55/272) compared with 15.5% (42/270) for vaginal prostaglandins (relative risk 1.29, 95% confidence interval 0.90 to 1.86). Different doses (100 micrograms three hourly and 200 micrograms six hourly) were used in the two trials that compared oral with vaginal misoprostol. The caesarean section rate was 21.8% in the oral misoprostol group compared with 13.5% for vaginal misoprostol (relative risk 1.62, 95% confidence interval 0.85 to 3.09). The uterine hyperstimulation rate with oral misoprostol was 37.5% (36/96) compared with 28% (25/89) for vaginal misoprostol (relative risk 1.32, 95% confidence interval 0.86 to 2.04). There was significant heterogeneity between these two trials. REVIEWER'S CONCLUSIONS: Oral misoprostol may be an effective method for labour induction. However clinically effective oral regimens may have an unacceptably high incidence of uterine hyperstimulation and possibly uterine rupture.

Female↗

PubMed2005

Systematic reviews of diagnostic tests: a guide to methods and application.

This chapter describes the basic steps in a systematic review to evaluate test accuracy, and the threats to validity of reviews inherent in each step. First, the problems to be addressed are specified in the form of well-structured questions (Step 1). This is a key step, as all other aspects of the review follow directly from the questions. Second, thorough literature searches are conducted to identify potentially relevant studies that shed light on the questions (Step 2). This is one essential feature that makes a review systematic. Third, the quality of the selected studies is assessed (Step 3). Fourth, the evidence concerning study characteristics and results is summarized, and differences between studies are explored (Step 4). When feasible and appropriate, meta-analysis helps in collating results. Finally, inferences and recommendations for practice are generated from interpretation and exploration of clinical relevance of the findings (Step 5). These steps are illustrated using a published review concerning the cervicovaginal fetal fibronectin test.

Decision Making↗

PubMed2004

From evidence to action.

Despite the availability of vast quantities of evidence from basic biomedical and clinical studies, a gap often exists between the optimal practice suggested by the evidence and actual practice. For many clinical situations, however, evidence is unavailable, of poor quality or contradictory. Out of necessity, clinicians have become accustomed to relying on non-evidence-based tools to make decisions. Out of habit, they rely on these tools even when high-quality evidence becomes available. Growing out of an increasing awareness of this problem, the evidence-based medicine (EBM) movement sought to empower clinicians to find the evidence most relevant to a specific clinical question. Various organizations have used EBM techniques to develop systematic reviews and practice guidelines to aid physicians in making evidence-based decisions. A systematic review follows a process of asking a clinical question, finding the relevant evidence, critically appraising the evidence and formulating conclusions and recommendations. Results are mixed on whether educating physicians about evidence-based recommendations is sufficient to change physician behavior. Barriers to adopting evidence-based best practice remain, including physician skepticism, patient expectations, fear of legal action, and distorted reimbursement systems. Additionally, despite enormous research efforts there remains a lack of high-quality evidence to guide care for many clinical situations.

Evidence-Based Medicine↗

PubMed2000

Planned caesarean section for term breech delivery.

BACKGROUND: Routine use of caesarean section for breech presentation is widespread. However poor outcomes after breech birth may be the result of underlying conditions causing breech presentation rather than damage during delivery. OBJECTIVES: The objective of this review was to assess the effects of planned caesarean section for breech presentation on measures of pregnancy outcome. SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth trials register and the Cochrane Controlled Trials register. Date of last search: October 1997. SELECTION CRITERIA: Randomised trials comparing planned caesarean section for breech presentation with planned vaginal delivery. DATA COLLECTION AND ANALYSIS: Reviewers assessed trial eligibility and quality. MAIN RESULTS: Two studies involving 313 women were included. Caesarean section was done in 93% (119/128) of women allocated to planned caesarean section and 54% (99/185) of women in the planned vaginal delivery groups. The policy of planned caesarean section was associated with significantly increased maternal morbidity (relative risk 1.31, 95% confidence interval 1.02 to 1.68) and reduced short term neonatal morbidity (relative risk 0.26, 95% confidence interval 0.08 to 0.88). The studies were unable to detect differences in brachial plexus injuries, low Apgar scores or perinatal mortality. REVIEWER'S CONCLUSIONS: There is not enough evidence to evaluate the use of a policy of planned caesarean section for breech presentation. A large Canadian trial addressing this question is currently underway.

Breech Presentation↗

PubMed2005

Meta-analysis and structured literature review in radiology.

The overall goal of a systematic review or meta-analysis is to combine results of previous studies to arrive at summary conclusions about a body of research. In radiology, systematic reviews or meta-analyses can be used to calculate a summary estimate of effect size of a treatment that used imaging data to assess outcomes in observational or randomized controlled clinical trials, estimate the clinical effectiveness of an imaging-guided therapy procedure, evaluate the summary diagnostic accuracy of an imaging test, or synthesize results of economic evaluations that used imaging data. This article outlines the general concepts of structured literature reviews and discusses the approaches for conducting a meta-analysis in radiology, emphasizing the methods available for data synthesis and handling heterogeneity between and among studies.

Humans↗

PubMed2001

Galantamine for Alzheimer's disease.

BACKGROUND: Galantamine (also called galanthamine, marketed as Reminyl (Janssen)) can be isolated from several plants, including daffodil bulbs, and now synthesized. Galantamine is a specific, competitive, and reversible acetylcholinesterase inhibitor. It is also an allosteric modulator at nicotinic cholinergic receptor sites potentiating cholinergic nicotinic neurotransmission. A small number of early studies showed mild cognitive and global benefits for patients with Alzheimer's disease, and recently several multicentre clinical trials have been published with positive findings. Galantamine has received regulatory approval in Sweden, is available in Austria, and awaits marketing approval in the United States, Europe, and other countries. OBJECTIVES: The objective of this review is to assess the clinical effects of galantamine in patients with probable Alzheimer's disease, and to investigate potential moderators of an effect. SEARCH STRATEGY: The Cochrane Dementia Group specialized register of clinical trials was searched using the terms 'galantamine,' and 'galanthamine' (15 February 2000) as was the Cochrane Controlled Trials Register (2000, Issue 2). These terms were also used to search the following databases: EMBASE, MEDLINE, PsychLit; Combined Health Information Database, NRR (National Research Register), ADEAR (Alzheimer's Disease Education and Referral Centre clinical database, BIOMED (Biomedicine and Health), Glaxo-Wellcome Clinical Trials Register, National Institutes of Health Clinical Trials Databases, Current Controlled Trials, Dissertation Abstracts (mainly North American dissertations) 1961-1994, Index to UK Theses (British dissertations) 1970-1994. Published reviews were inspected for further sources. Additional information was collected from an unpublished investigational brochure for galantamine. SELECTION CRITERIA: Trials selected were randomized, double-blind, parallel-group, and unconfounded comparisons of galantamine with placebo for a treatment duration of greater than 4 weeks in people with Alzheimer's disease. DATA COLLECTION AND ANALYSIS: Data were extracted independently by the reviewers and pooled where appropriate and possible. The pooled odds ratios (95%CI) or the average differences (95%CI) were estimated. Intention-to-treat and observed cases data were both reported, if the data were available to be reported. -Outcomes of interest include the Alzheimer's Disease Assessment Scale-cognitive subscale (ADAS-cog), clinical global impression of change (CIBIC-plus or CGIC), Alzheimer's Disease Cooperative Study/Activities of Daily Living (ADCS-ADL), Disability Assessment for Dementia scale (DAD) and Neuropsychiatric Inventory (NPI). - Potential moderating variables of a treatment effect included trial duration and dose. MAIN RESULTS: Seven trials were identified that met criteria for entry, with 6 being Phase II or III industry-sponsored multicentre trials. One was of 12 weeks duration; one of 5 months; one of 29 weeks; and the rest of 6 months duration. Trials of 5 months or more were aggregated in the analyses as '6 months'. Overall, galantamine showed significant treatment effects at daily doses of 16-32 mg/d for trials of 3- to 6-months duration. For global ratings, trials of 3 months duration with doses of 24-32mg/d (Odds Ratio (OR) 2.2; 95%CI 1.4 to 3.7) and 36mg/d (OR 3.3; 95%CI 1.2 to 9.3) were statistically significant in favour of treatment. For trials of 6 months duration (5-months to 29 weeks), only doses of 8mg/d failed to be statistically significant (24mg: OR 2.0; 95%CI 1.5 to2.5; 32mg: OR 1.9; 95%CI 1.4 to 2.5). For cognitive function over 6 months duration: at a 24mg/d, improvements measured -3.5 points (k=3; 95%CI -4.3 to -2.8) on weighted mean difference on the ADAS-Cog scale, and -4.0 points at 32mg/d (k=2; 95%CI -5.0 to -3.0). Both observed cases (WMD 3.8; 95%CI 0.3 to 7.3) and intention to treat analyses using the Disability Assessment of Dementia gave statistically significant results in favour of treatment for daily doses of 32mg for 6 months duration. The small number of trials available for analysis, however, limited the power of analyses to detect differences. Galantamine consistently failed to show statistically significant treatment effects at doses of 8mg/day. Galantamine's adverse effects appear similar to those of other cholinesterase inhibitors, in that it tends to produce gastrointestinal effects acutely and with dosage increases. Overall, people treated with galantamine at doses of 24-32 mg/d were more likely to discontinue participation in most trials than were people treated with lower doses or placebo, but in the one trial with a slower rate of titration the discontinuation rate was not significantly greater than placebo for the 16 mg/day dose. (ABSTRACT TRUNCATED)

Alzheimer Disease↗

PubMed2001

Melatonin for preventing and treating jet lag.

BACKGROUND: Jet-lag commonly affects air travellers who cross several time zones. It results from the body's internal rhythms being out of step with the day-night cycle at the destination. Melatonin is a pineal hormone that plays a central part in regulating bodily rhythms and has been used as a drug to re-align them with the outside world. OBJECTIVES: To assess the effectiveness of oral melatonin taken in different dosage regimens for alleviating jet-lag after air travel across several time zones. SEARCH STRATEGY: We searched the Cochrane Controlled Trials Register, MEDLINE, EMBASE, PsychLit and Science Citation Index electronically, and the journals 'Aviation, Space and Environmental Medicine' and 'Sleep' by hand. We searched citation lists of relevant studies for other relevant trials. We asked principal authors of relevant studies to tell us about unpublished trials. Reports of adverse events linked to melatonin use outside randomised trials were searched for systematically in 'Side Effects of Drugs' (SED) and SED Annuals, 'Reactions Weekly', MEDLINE, and the adverse drug reactions databases of the WHO Uppsala Monitoring Centre (UMC) and the US Food & Drug Administration. SELECTION CRITERIA: Randomised trials in airline passengers, airline staff or military personnel given oral melatonin, compared with placebo or other medication. Outcome measures should consist of subjective rating of jet-lag or related components, such as subjective wellbeing, daytime tiredness, onset and quality of sleep, psychological functioning, duration of return to normal, or indicators of circadian rhythms. DATA COLLECTION AND ANALYSIS: : Ten trials met the inclusion criteria. All compared melatonin with placebo; one in addition compared it with a hypnotic, zolpidem. Nine of the trials were of adequate quality to contribute to the assessment, one had a design fault and could not be used in the assessment. Reports of adverse events outside trials were found through MEDLINE, 'Reactions Weekly', and in the WHO UMC database. MAIN RESULTS: : Nine of the ten trials found that melatonin, taken close to the target bedtime at the destination (10pm to midnight), decreased jet-lag from flights crossing five or more time zones. Daily doses of melatonin between 0.5 and 5mg are similarly effective, except that people fall asleep faster and sleep better after 5mg than 0.5mg. Doses above 5mg appear to be no more effective. The relative ineffectiveness of 2mg slow-release melatonin suggests that a short-lived higher peak concentration of melatonin works better. Based on the review, the number needed to treat (NNT) is 2. The benefit is likely to be greater the more time zones are crossed, and less for westward flights. The timing of the melatonin dose is important: if it is taken at the wrong time, early in the day, it is liable to cause sleepiness and delay adaptation to local time. The incidence of other side effects is low. Case reports suggest that people with epilepsy, and patients taking warfarin may come to harm from melatonin. REVIEWER'S CONCLUSIONS: Melatonin is remarkably effective in preventing or reducing jet-lag, and occasional short-term use appears to be safe. It should be recommended to adult travellers flying across five or more time zones, particularly in an easterly direction, and especially if they have experienced jet-lag on previous journeys. Travellers crossing 2-4 time zones can also use it if need be. The pharmacology and toxicology of melatonin needs systematic study, and routine pharmaceutical quality control of melatonin products must be established. The effects of melatonin in people with epilepsy, and a possible interaction with warfarin, need investigation.

Antioxidants↗

PubMed2004

Differences between systematic reviews and health technology assessments: a trade-off between the ideals of scientific rigor and the realities of policy making.

OBJECTIVES: To elucidate important differences between a health technology assessment (HTA) and a systematic review, using an HTA of positron emission tomography (PET) as an example. METHODS: Interviews with seventeen individuals who were authors or users of the PET HTA. RESULTS: Those interviewed identified seven areas in which HTAs often differ from traditional systematic reviews: (i) methodological standards (HTAs may include literature of relatively poor methodological quality if a topic is of importance to decision-makers), (ii) replication of previous studies (relatively common for HTAs but not systematic reviews), (iii) choice of topics (more policy oriented for HTAs, while systematic reviews tend to be driven by researcher interest), (iv) inclusion of content experts and policy-makers as authors (policy-makers more likely to be included in HTAs, although there are potential conflicts of interest), (v) inclusion of economic evaluations (more often with HTAs, although economic evaluations based upon poor clinical data may not be useful), (vi) making policy recommendations (more likely with HTAs, although this must be done with caution), and (vii) dissemination of the report (more often actively done for HTAs). CONCLUSIONS: This case study of an HTA of PET scanning confirms that HTAs are a bridge between science and policy and require a balance between the ideals of scientific rigor and the realities of policy making.

Cost-Benefit Analysis↗