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Biomedical subjects

N Black

Publications and source records attributed to N Black.

At least 37 records · Page 2Linked to original sources
PubMed1999

Effect of open peer review on quality of reviews and on reviewers' recommendations: a randomised trial.

OBJECTIVES: To examine the effect on peer review of asking reviewers to have their identity revealed to the authors of the paper. DESIGN: Randomised trial. Consecutive eligible papers were sent to two reviewers who were randomised to have their identity revealed to the authors or to remain anonymous. Editors and authors were blind to the intervention. MAIN OUTCOME MEASURES: The quality of the reviews was independently rated by two editors and the corresponding author using a validated instrument. Additional outcomes were the time taken to complete the review and the recommendation regarding publication. A questionnaire survey was undertaken of the authors of a cohort of manuscripts submitted for publication to find out their views on open peer review. RESULTS: Two editors' assessments were obtained for 113 out of 125 manuscripts, and the corresponding author's assessment was obtained for 105. Reviewers randomised to be asked to be identified were 12% (95% confidence interval 0.2% to 24%) more likely to decline to review than reviewers randomised to remain anonymous (35% v 23%). There was no significant difference in quality (scored on a scale of 1 to 5) between anonymous reviewers (3.06 (SD 0.72)) and identified reviewers (3.09 (0.68)) (P=0.68, 95% confidence interval for difference - 0.19 to 0.12), and no significant difference in the recommendation regarding publication or time taken to review the paper. The editors' quality score for reviews (3.05 (SD 0.70)) was significantly higher than that of authors (2.90 (0.87)) (P<0.005, 95%confidence interval for difference - 0.26 to - 0.03). Most authors were in favour of open peer review. CONCLUSIONS: Asking reviewers to consent to being identified to the author had no important effect on the quality of the review, the recommendation regarding publication, or the time taken to review, but it significantly increased the likelihood of reviewers declining to review.

Decision Making↗
PubMed1999

Evidence-based surgery: A passing fad?

Recent years have witnessed the development of a new movement within health care: the promotion of "evidence-based medicine" (EBM). EBM is about integrating individual clinical expertise and the best external evidence derived from scientific research. Advocates claim that much medical practice is based too much on opinion and experience and insufficiently on research evidence. Their approach would increase the quality of care and its efficiency. This paper describes the principal steps in the evidence-based approach-systematic reviews of the literature and meta-analyses-and its shortcomings in surgery. These include the reliance of EBM on randomized trials, the lack of generalizability of scientific evidence to individual patients, the lack of attention to third party interests, the threat to the "art" of medicine, and the dangers of an oversimplistic approach. Although EBM clearly has a place, it does not have all the answers.

Endoscopy↗
PubMed1999

Development of the review quality instrument (RQI) for assessing peer reviews of manuscripts.

Research on the value of peer review is limited by the lack of a validated instrument to measure the quality of reviews. The aim of this study was to develop a simple, reliable, and valid scale that could be used in studies of peer review. A Review Quality Instrument (RQI) that assesses the extent to which a reviewer has commented on five aspects of a manuscript (importance of the research question, originality of the paper, strengths and weaknesses of the method, presentation, interpretation of results) and on two aspects of the review (constructiveness and substantiation of comments) was devised and tested. Its internal consistency was high (Cronbach's alpha 0.84). The mean total score (based on the seven items each scored on a 5-point Likert scale from 1 to 5) had good test-retest (Kw = 1.00) and inter-rater (Kw = 0.83) reliability. There was no evidence of floor or ceiling effects, construct validity was evident, and the respondent burden was acceptable (2-10 minutes). Although improvements to the RQI should be pursued, the instrument can be recommended for use in the study of peer review.

Humans↗
PubMed1999

Predicting coronary disease risk based on short-term RR interval measurements: a neural network approach.

Coronary heart disease is a multifactorial disease and it remains the most common cause of death in many countries. Heart rate variability has been used for non-invasive measurement of parasympathetic activity and prediction of cardiac death. Patterns of heart rate variability associated with respiratory sinus arrhythmia have recently been considered as possible indicators of coronary heart disease risk in asymptomatic subjects. The aim of this work is to detect individuals at varying risk of coronary heart disease based on short-term heart rate variability measurements under controlled respiration. Artificial neural networks are used to recognise Poincaré-plot-encoded heart rate variability patterns related to coronary heart disease risk. The results indicate a relatively coarse binary representation of Poincaré plots could be superior to an analogue encoding which, in principle, carries more information.

Coronary Disease↗
PubMed1999

Effect of blinding and unmasking on the quality of peer review.

The objectives of this study were to see whether, in the opinion of authors, blinding or unmasking or a combination of the two affects the quality of reviews and to compare authors' and editors' assessments. In a trial conducted in the British Medical Journal, 527 consecutive manuscripts were randomized into one of three groups, and each was sent to two reviewers, who were randomized to receive a blinded or an unblinded copy of the manuscript. Review quality was assessed by two editors and the corresponding author. There was no significant difference in assessment between groups or between editors and authors. Reviews recommending publication were scored more highly than those recommending rejection.

Authorship↗
PubMed1999

Improving clinical decision support through case-based data fusion.

This paper presents an information fusion technique based on a knowledge discovery model, and the case-based reasoning decision framework. Using signal data and database records from the heart disease risk estimation domain, three data fusion methods are discussed. Two of these methods combine information at the retrieval-outcome level, and one method merges data at the discovery-input level. The result of these three models are compared and evaluated against the performance of single-source models. It is shown that the methods that fuse information at the retrieval-outcome level are significantly superior.

Adult↗
PubMed1999

What observational studies can offer decision makers.

Observational studies, for example cohort and case-control studies in which patients are allocated treatment on a non-random basis, are thought by some investigators to be flawed. This view results from the fact that, unlike experimental methods (randomized controlled trials; RCTs), the results of such observational studies are vulnerable to confounding. However, this view assumes that satisfactory adjustment of differences in risk or prognosis between treatment groups is impossible and it ignores some of the limitations of RCTs. While many of the problems involved in conducting RCTs could be overcome, the practical implications for researchers and funding bodies mean this is often not possible. In such circumstances, observational studies offer an alternative to an absence of any scientific evidence. While making use of observational methods, researchers must acknowledge the associated limitations: the inevitable inability to take unknown confounders into account, non-blinding of practitioners and patients, and the inclusion of practitioners' and patients' treatment preferences.

Case-Control Studies↗
PubMed1999

Where do UK health services researchers publish their findings?

Health services research has emerged as the third vital requirement for understanding and improving health care, alongside basic science and clinical research. This has coincided with more stringent management of research, in particular by funding bodies. The latter are seeking to use bibliographic databases to aid the monitoring of the output of their investments. The principal source of data in the UK is the Research Outputs Database (ROD) set up by the Wellcome Trust primarily to monitor basic and clinical research. Health services researchers' output is difficult to monitor in view of the large number and wide variety of journals in which they publish. In addition, nearly half the journals (representing 35% of the articles) are not currently covered by the ROD. Funding bodies will underestimate the quantity of health services researchers' output unless they take these findings into account.

Clinical Medicine↗
PubMed1999

Threats to applicability of randomised trials: exclusions and selective participation.

BACKGROUND: Although the randomised controlled trial (RCT) is regarded as the 'gold standard' in terms of evaluating the effectiveness of interventions, it is susceptible to challenges to its external validity if those participating are unrepresentative of the reference population for whom the intervention in question is intended. In the past, reporting on numbers and types of potential subjects that have been excluded by design, and centres, clinicians or patients that have elected not to participate, has generally been poor, and the threat to inference posed by possible selection bias is unclear. METHODS: A systematic review was undertaken, based largely on MEDLINE and EMBASE with follow-up of cited references, to assess the extent, nature and importance of excluding potential subjects or the unwillingness of particular centres, clinicians or patients to participate. RESULTS: RCTs vary widely in the extent to which potential future recipients of treatment are included. The reasons cited for excluding certain categories of patient may be medical or scientific. Medical reasons include a high risk of adverse effects and the belief that benefit will be relatively small or absent (or has already been established) in the groups in question. Scientific reasons include more precise estimates of treatment effect because of a relatively homogeneous sample and the reduction of potential bias by excluding those individuals most likely to be lost to follow-up. Many RCTs have blanket exclusions, such as the elderly, women and ethnic minorities, but reasons for these exclusions are seldom given. Evaluative research is undertaken predominantly in university or teaching centres. Non-randomised studies are more likely than RCTs to include non-teaching centres. The effect of patient non-participation appears to depend on whether the RCT is concerned with treatment of an existing condition or with disease prevention. Participants in treatment trials tend to be more severely ill than those who do not participate. In contrast, those who participate in prevention trials are more likely to have adopted a healthy lifestyle than those who decline. Most evaluative studies fail to document adequately the characteristics of those who, while eligible, do not participate. However, subjects included in RCTs (i.e. eligible and participating) tend to have a different prognosis than patients identified from clinical databases. CONCLUSIONS: Narrow inclusion criteria may offer benefits such as increased precision and reduced loss to follow-up, but there are important disadvantages, such as uncertainty about extrapolation of results, which may result in denial of effective treatment to groups who might benefit, and delay in obtaining definitive results because of reduced recruitment rate. Selective participation by teaching centres and sicker patients in treatment RCTs may exaggerate the measured treatment effect. Prevention trials, on the other hand, may underestimate effects as participants have less capacity to benefit.

Australia↗
PubMed1999

Consensus development methods: a review of best practice in creating clinical guidelines.

BACKGROUND: Although there is debate about the appropriate place of guidelines in clinical practice, guidelines can be seen as one way of assisting clinicians in decision-making. Given the likely diversity of opinion that any group of people may display when considering a topic, methods are needed for organising subjective judgements. Three principal methods (Delphi, nominal group technique, consensus development conference) exist which share the common objective of synthesising judgements when a state of uncertainty exists. OBJECTIVES: To identify the factors that shape and influence the clinical guidelines that emerge from consensus development methods and to make recommendations about best practice in the use of such methods. METHODS: Five electronic databases were searched: Medline (1966-1996), PsychLIT (1974-1996), Social Science Citation Index (1990-1996), ABI Inform and Sociofile. From the searches and reference lists of articles a total of 177 empirical and review articles were selected for review. RESULTS: The output from consensus development methods may be affected by: the way the task is set (choice of cues, recognition of contextual cues, the focus of the task, the comprehensiveness of the scenarios); the selection of participants (choice of individuals, degree of homogeneity of the group, their background, their number); the selection and presentation of scientific information (format, extent to which its quality and content is assessed); the way any interaction is structured (number of rating rounds, ensuring equitable participation, physical environment for meetings); and the method of synthesising individual judgements (definition of agreement, rules governing outliers, method of mathematical aggregation). CONCLUSIONS: Although a considerable amount of research has been carried out, many aspects have not been investigated sufficiently. For the time being at least, advice on those aspects has, therefore, to be based on the user's own commonsense and the experience of those who have used or participated in these methods. Even in the long term, some aspects will not be amenable to scientific study. Meanwhile, adherence to best practice will enhance the validity, reliability and impact of the clinical guidelines produced.

Benchmarking↗
PubMed1998

What makes a good reviewer and a good review for a general medical journal?

CONTEXT: Selecting peer reviewers who will provide high-quality reviews is a central task of editors of biomedical journals. OBJECTIVES: To determine the characteristics of reviewers for a general medical journal who produce high-quality reviews and to describe the characteristics of a good review, particularly in terms of the time spent reviewing and turnaround time. DESIGN, SETTING, AND PARTICIPANTS: Surveys of reviewers of the 420 manuscripts submitted to BMJ between January and June 1997. MAIN OUTCOME MEASURES: Review quality was assessed independently by 2 editors and by the corresponding author using a newly developed 7-item review quality instrument. RESULTS: Of the 420 manuscripts, 345 (82%) had 2 reviews completed, for a total of 690 reviews. Authors' assessments of review quality were available for 507 reviews. The characteristics of reviewers had little association with the quality of the reviews they produced (explaining only 8% of the variation), regardless of whether editors or authors defined the quality of the review. In a logistic regression analysis, the only significant factor associated with higher-quality ratings by both editors and authors was reviewers trained in epidemiology or statistics. Younger age also was an independent predictor for editors' quality assessments, while reviews performed by reviewers who were members of an editorial board were rated of poorer quality by authors. Review quality increased with time spent on a review, up to 3 hours but not beyond. CONCLUSIONS: The characteristics of reviewers we studied did not identify those who performed high-quality reviews. Reviewers might be advised that spending longer than 3 hours on a review on average did not appear to increase review quality as rated by editors and authors.

Data Collection↗
PubMed1998

Effect of blinding and unmasking on the quality of peer review: a randomized trial.

CONTEXT: Little research has been conducted into the quality of peer review and, in particular, the effects of blinding peer reviewers to authors' identities or masking peer reviewers' identities. OBJECTIVE: To determine whether concealing authors' identities from reviewers (blinding) and/or revealing the reviewer's identity to a coreviewer (unmasking) affects the quality of reviews, the time taken to carry out reviews, and the recommendation regarding publication. DESIGN AND SETTING: Randomized trial of 527 consecutive manuscripts submitted to BMJ, which were randomized and each sent to 2 peer reviewers. INTERVENTIONS: Manuscripts were randomized as to whether the reviewers were unmasked, masked, or uninformed that a study was taking place. Two reviewers for each manuscript were randomized to receive either a blinded or an unblinded version. MAIN OUTCOME MEASURES: Mean total quality score, time taken to carry out the review, and recommendation regarding publication. RESULTS: Of the 527 manuscripts entered into the study, 467 (89%) were successfully randomized and followed up. The mean total quality score was 2.87. There was little or no difference in review quality between the masked and unmasked groups (scores of 2.82 and 2.96, respectively) and between the blinded and unblinded groups (scores of 2.87 and 2.90, respectively). There was no apparent Hawthorne effect. There was also no significant difference between groups in the recommendations regarding publication or time taken to review. CONCLUSIONS: Blinding and unmasking made no editorially significant difference to review quality, reviewers' recommendations, or time taken to review. Other considerations should guide decisions as to the form of peer review adopted by a journal, and improvements in the quality of peer review should be sought via other means.

Authorship↗