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Biomedical subjects

David Moher

Publications and source records attributed to David Moher.

At least 19 recordsLinked to original sources
PubMed2006

A review of interventions triggered by hepatitis A infected food-handlers in Canada.

BACKGROUND: In countries with low hepatitis A (HA) endemicity, infected food handlers are the source of most reported foodborne outbreaks. In Canada, accessible data repositories of infected food handler incidents are not available. We undertook a systematic review of such incidents to evaluate the extent of viral transmission through food contamination and the scope of post-exposure prophylaxis (PEP) interventions. METHODS: A systematic search of MEDLINE and EMBASE was conducted to identify published reports of incidents in Canada. An expanded search of a news repository (i.e., transcripts from newspapers and newscasts) was also conducted to identify the location and timing of an incident, which was used to retrieve the related report by contacting local public health departments. Data pertaining to case identification, public health risk, PEP interventions, and associated costs was independently abstracted by two reviewers and summarized according to incidents with and without large PEP interventions. RESULTS: A total of 16 incidents were identified from 1998-2004. There were approximately 3 incidents requiring public notification per year. Only 12.5% of incidents were described in published reports, indicating that published data significantly underestimated the number of incidents and PEP interventions. Data pertaining to the remaining incidents was unpublished, sparse and highly dispersed at the local public health level. Six of the 16 incidents required large PEP interventions to immunize on average 5000 potentially exposed individuals. Secondary transmission was low. Characteristics of incidents requiring large PEP interventions included potentially infectious food handlers working with uncooked food for a prolonged duration in high-volume grocery stores in high-density urban areas. CONCLUSION: Infected food handlers with hepatitis A virus (HAV) requiring public notification are not infrequent in Canada. Published data severely underestimated the burden of PEP intervention. Better and consistent reporting at the local and national level as well as a national data repository should be considered for the management of future incidents.

Canada↗
PubMed2006

Does the CONSORT checklist improve the quality of reports of randomised controlled trials? A systematic review.

OBJECTIVE: To determine whether the adoption of the CONSORT checklist is associated with improvement in the quality of reporting of randomised controlled trials (RCTs). DATA SOURCES: MEDLINE, EMBASE, Cochrane CENTRAL, and reference lists of included studies and of experts were searched to identify eligible studies published between 1996 and 2005. STUDY SELECTION: Studies were eligible if they (a) compared CONSORT-adopting and non-adopting journals after the publication of CONSORT, (b) compared CONSORT adopters before and after publication of CONSORT, or (c) a combination of (a) and (b). Outcomes examined included reports for any of the 22 items on the CONSORT checklist or overall trial quality. DATA SYNTHESIS: 1128 studies were retrieved, of which 248 were considered possibly relevant. Eight studies were included in the review. CONSORT adopters had significantly better reporting of the method of sequence generation (risk ratio [RR], 1.67; 95% CI, 1.19-2.33), allocation concealment (RR, 1.66; 95% CI, 1.37-2.00) and overall number of CONSORT items than non-adopters (standardised mean difference, 0.83; 95% CI, 0.46-1.19). CONSORT adoption had less effect on reporting of participant flow (RR, 1.14; 95% CI, 0.89-1.46) and blinding of participants (RR, 1.09; 95% CI, 0.84-1.43) or data analysts (RR, 5.44; 95% CI, 0.73-36.87). In studies examining CONSORT-adopting journals before and after the publication of CONSORT, description of the method of sequence generation (RR, 2.78; 95% CI, 1.78-4.33), participant flow (RR, 8.06; 95% CI, 4.10-15.83), and total CONSORT items (standardised mean difference, 3.67 items; 95% CI, 2.09-5.25) were improved after adoption of CONSORT by the journal. CONCLUSIONS: Journal adoption of CONSORT is associated with improved reporting of RCTs.

Editorial Policies↗
PubMed2006

Review conclusions by Ernst and Canter regarding spinal manipulation refuted.

In the April 2006 issue of the Journal of Royal Society of Medicine, Ernst and Canter authored a review of the most recent systematic reviews on the effectiveness of spinal manipulation for any condition. The authors concluded that, except for back pain, spinal manipulation is not an effective intervention for any condition and, because of potential side effects, cannot be recommended for use at all in clinical practice. Based on a critical appraisal of their review, the authors of this commentary seriously challenge the conclusions by Ernst and Canter, who did not adhere to standard systematic review methodology, thus threatening the validity of their conclusions. There was no systematic assessment of the literature pertaining to the hazards of manipulation, including comparison to other therapies. Hence, their claim that the risks of manipulation outweigh the benefits, and thus spinal manipulation cannot be recommended as treatment for any condition, was not supported by the data analyzed. Their conclusions are misleading and not based on evidence that allow discrediting of a large body of professionals using spinal manipulation.

Editorial↗
PubMed2006

An alternative to the hand searching gold standard: validating methodological search filters using relative recall.

BACKGROUND: Search filters or hedges play an important role in evidence-based medicine but their development depends on the availability of a "gold standard"--a reference standard against which to establish the performance of the filter. We demonstrate the feasibility of using relative recall of included studies from multiple systematic reviews to validate methodological search filters as an alternative to validation against a gold standard formed through hand searching. METHODS: We identified 105 Cochrane reviews that used the Highly Sensitive Search Strategy (HSSS), included randomized or quasi-randomized controlled trials, and reported their included studies. We measured the ability of two published and one novel variant of the HSSS to retrieve the MEDLINE-index studies included in these reviews. RESULTS: The systematic reviews were comprehensive in their searches. 72% of included primary studies were indexed in MEDLINE. Relative recall of the three strategies ranged from .98 to .91 across all reviews and more comprehensive strategies showed higher recall. CONCLUSION: An approach using relative recall instead of a hand searching gold standard proved feasible and produced recall figures that were congruent with previously published figures for the HSSS. This technique would permit validation of a methodological filter using a collection of approximately 100 studies of the chosen design drawn from the included studies of multiple systematic reviews that used comprehensive search strategies.

Abstracting and Indexing↗
PubMed2006

How effective is tetracaine 4% gel, before a peripherally inserted central catheter, in reducing procedural pain in infants: a randomized double-blind placebo controlled trial [ISRCTN75884221].

BACKGROUND: Procedural pain relief is sub-optimal in infants, especially small and vulnerable ones. Tetracaine gel 4% (Ametop, Smith-Nephew) provides pain relief in children and larger infants, but its efficacy in smaller infants and for peripherally inserted central catheters (PICC) remains uncertain. The objective of this trial was to assess the safety and efficacy of tetracaine gel on the pain response of very low birth weight (VLBW) infants during insertion of a PICC. METHODS: Medically stable infants greater than or equal to 24 weeks gestation, requiring a non-urgent PICC, were included. Following randomization and double blinding, 1.1 g of tetracaine or placebo was applied to the skin for 30 minutes. The PICC was inserted according to a standard protocol. Pain was assessed using the Premature Infant Pain Profile (PIPP). A 3-point change in the pain score was considered clinically significant, leading to a sample size of 54 infants, with 90% statistical power. Local skin reactions and immediate adverse cardiorespiratory events were noted. The primary outcome, PIPP score at 1 minute, was analysed using an independent Student's t-test. RESULTS: Fifty-four infants were included, 27 +/- 2 weeks gestation, 916 +/- 292 grams and 6.5 +/- 3.2 days of age. Baseline characteristics were similar between groups. The mean PIPP score in the first minute was 10.88 in the treatment group as compared to 11.74 in the placebo group (difference 0.86, 95% CI -1.86, 3.58). Median duration of crying in non-intubated infants was 181 seconds in the tetracaine group compared to 68 seconds in the placebo group (difference -78, 95% CI -539, 117). Local skin erythema was observed transiently in 4 infants (3 in the treatment and 1 in the placebo group). No serious harms were observed. CONCLUSION: Tetracaine 4% when applied for 30 minutes was not beneficial in decreasing procedural pain associated with a PICC in very small infants.

Administration, Topical↗
PubMed2006

Reporting randomized, controlled trials of herbal interventions: an elaborated CONSORT statement.

Herbal medicinal products are widely used, vary greatly in content and quality, and are actively tested in randomized, controlled trials (RCTs). The authors' objective was to develop recommendations for reporting RCTs of herbal medicine interventions, based on the need to elaborate on the 22-item CONSORT (Consolidated Standards of Reporting Trials) checklist. Telephone calls were made and a consensus meeting was held with 16 participants in Toronto, Canada, to develop these recommendations. The group agreed on context-specific elaborations of 9 CONSORT checklist items for RCTs of herbal medicines. Item 4, concerning the herbal medicine intervention, required the most extensive elaboration. These recommendations have been developed to improve the reporting of RCTs using herbal medicine interventions.

Herbal Medicine↗
PubMed2006

Can electronic search engines optimize screening of search results in systematic reviews: an empirical study.

BACKGROUND: Most electronic search efforts directed at identifying primary studies for inclusion in systematic reviews rely on the optimal Boolean search features of search interfaces such as DIALOG and Ovid. Our objective is to test the ability of an Ultraseek search engine to rank MEDLINE records of the included studies of Cochrane reviews within the top half of all the records retrieved by the Boolean MEDLINE search used by the reviewers. METHODS: Collections were created using the MEDLINE bibliographic records of included and excluded studies listed in the review and all records retrieved by the MEDLINE search. Records were converted to individual HTML files. Collections of records were indexed and searched through a statistical search engine, Ultraseek, using review-specific search terms. Our data sources, systematic reviews published in the Cochrane library, were included if they reported using at least one phase of the Cochrane Highly Sensitive Search Strategy (HSSS), provided citations for both included and excluded studies and conducted a meta-analysis using a binary outcome measure. Reviews were selected if they yielded between 1000-6000 records when the MEDLINE search strategy was replicated. RESULTS: Nine Cochrane reviews were included. Included studies within the Cochrane reviews were found within the first 500 retrieved studies more often than would be expected by chance. Across all reviews, recall of included studies into the top 500 was 0.70. There was no statistically significant difference in ranking when comparing included studies with just the subset of excluded studies listed as excluded in the published review. CONCLUSION: The relevance ranking provided by the search engine was better than expected by chance and shows promise for the preliminary evaluation of large results from Boolean searches. A statistical search engine does not appear to be able to make fine discriminations concerning the relevance of bibliographic records that have been pre-screened by systematic reviewers.

Abstracting and Indexing↗
PubMed2006

Improving the quality of reporting of randomized controlled trials evaluating herbal interventions: implementing the CONSORT statement [corrected].

BACKGROUND: Given that herbal medicinal products are widely used, vary greatly in content and quality, and are actively tested in randomized controlled trials (RCTs), such RCTs must clearly report the specifics of the intervention. OBJECTIVE: Our objective was to develop recommendations for reporting RCTs of herbal medicine interventions. METHODS: We identified and invited potential participants with expertise in clinical trial methodology, clinical trial reporting, pharmacognosy, herbal medicinal products, medical statistics, and/or herbal product manufacturing to participate in phone calls and a consensus meeting. Three phases were conducted: (1) Premeeting item generation via telephone calls, (2) Consensus meeting, and (3) Postmeeting feedback. Sixteen experts participated in premeeting phone calls for item generation, and 14 participants attended a consensus meeting in Toronto, Ontario, Canada, in June of 2004. During the consensus meeting, a modified Delphi technique was used to aid discussion and debate of information required for reporting RCTs of herbal medicines. RESULTS: After extensive discussion, the group decided that context-specific elaborations of nine Consolidated Standards of Reporting Trials (CONSORT) items to RCTs of herbal medicines were necessary: Item 1 (Title and Abstract), 2 (Background), 3 (Participants), 4 (Interventions), 6 (Outcomes), 15 (Baseline data), 20 (Interpretation), 21 (Generalizability), and 22 (Overall evidence). DISCUSSION: The elaboration of item 4 of the CONSORT statement outlines specific information required for complete reporting of the herbal medicine intervention. The reporting suggestions presented will support clinical trialists, editors, and reviewers in reporting and reviewing RCTs of herbal medicines and readers in interpreting the results.

Consensus↗
PubMed2006

A systematic review identifies a lack of standardization in methods for handling missing variance data.

BACKGROUND AND OBJECTIVES: To describe and critically appraise available methods for handling missing variance data in meta-analysis (MA). METHODS: Systematic review. MEDLINE, EMBASE, Web of Science, MathSciNet, Current Index to Statistics, BMJ SearchAll, The Cochrane Library and Cochrance Colloquium proceedings, MA texts and references were searched. Any form of text was included: MA, method chapter, or otherwise. Descriptions of how to implement each method, the theoretic basis and/or ad hoc motivation(s), and the input and output variable(s) were extracted and assessed. Methods may be: true imputations, methods that obviate the need for a standard deviation (SD), or methods that recalculate the SD. RESULTS: Eight classes of methods were identified: algebraic recalculations, approximate algebraic recalculations, imputed study-level SDs, imputed study-level SDs from nonparametric summaries, imputed study-level correlations (e.g., for change-from-baseline SD), imputed MA-level effect sizes, MA-level tests, and no-impute methods. CONCLUSION: This work aggregates the ideas of many investigators. The abundance of methods suggests a lack of consistency within the systematic review community. Appropriate use of methods is sometimes suspect; consulting a statistician, early in the review process, is recommended. Further work is required to optimize method choice to alleviate any potential for bias and improve accuracy. Improved reporting is also encouraged.

Data Interpretation, Statistical↗
PubMed2006

Recommendations for reporting randomized controlled trials of herbal interventions: Explanation and elaboration.

Controlled trials that use randomized allocation are the best tool to control for bias and confounding in trials testing clinical interventions. Investigators must be sure to include information that is required by the reader to judge the validity and implications of the findings in the reports of these trials. In part, complete reporting of trials will allow clinicians to modify their clinical practice to reflect current evidence toward the improvement of clinical outcomes. The consolidated standards of reporting trials (CONSORT) statement was developed to assist investigators, authors, reviewers, and editors on the necessary information to be included in reports of controlled clinical trials. The CONSORT statement is applicable to any intervention, including herbal medicinal products. Controlled trials of herbal interventions do not adequately report the information suggested in CONSORT. Recently, reporting recommendations were developed in which several CONSORT items were elaborated to become relevant and complete for randomized controlled trials of herbal medicines. We expect that these recommendations will lead to more complete and accurate reporting of herbal trials. We wrote this explanatory document to outline the rationale for each recommendation and to assist authors in using them by providing the CONSORT items and the associated elaboration, together with examples of good reporting and empirical evidence, where available, for each. These recommendations for the reporting of herbal medicinal products presented here are open to revision as more evidence accumulates and critical comments are collected.

Complementary Therapies↗
PubMed2006

The reporting of randomized clinical trials using a surgical intervention is in need of immediate improvement: a systematic review.

OBJECTIVE: To assess the reporting of surgical interventions, care providers, and number of centers in randomized clinical trials. METHODS: Systematic review was performed to assess reports of randomized controlled trials assessing surgical procedure published in 2004. A standardized abstraction form was used to extract data. RESULTS: A total of 158 articles were included. Details on the intervention intended, such as the surgical procedure, were reported in 138 (87.3%) articles, anesthetic management in 56 (35.4%), preoperative care in 34 (15.2%), and postoperative care in 78 (49.4%). How the experimental surgical intervention was carried out was reported in 64 articles (40.5%). Most trials were conducted in single centers (n = 109, 69.0%). The setting was reported in only 11 articles, and the volume of interventions performed was only reported in 5. Selection criteria were reported for care providers in 64 articles (40.5%). The number of care providers performing the intervention was reported in 51 articles (32.2%). The quality of reporting was low as assessed by CLEAR NPT (a 10-items checklist specifically developed to assess the reporting quality of RCTs assessing nonpharmacologic treatment). CONCLUSIONS: Inadequate reporting on the management of the surgical procedure, care providers, and surgery center may introduce bias in RCTs of surgical interventions, making their results questionable. We recommend extending the CONSORT Statement to surgical interventions.

Humans↗
PubMed2006

Improving the quality of randomized controlled trials in Chinese herbal medicine, part I: clinical trial design and methodology.

OBJECTIVE: To discuss the quality of randomized controlled trials (RCTs) in Chinese herbal medicine (CHM) with respect to design and methodology, and provide suggestions for further improvement in future clinical trials. METHODS: A search of the Cochrane Library was conducted to identify RCTs of CHM on line in July 2005. Quality of the RCTs was assessed using a 11-item checklist modified from the revised CONSORT statement, with 2 items specific to CHM (i.e. herb preparation form and quality control of herbs). RESULTS: The search yielded 167 RCTs that were selected for assessment. All trials included statements about the interventions, objectives, primary outcome design, statistical methods, and herb preparation form. Although 163 (97.6%) trials reported inclusion criteria, exclusion criteria were only reported in 26 (15.6%) trials. Fewer than 10% of trials clearly stated the random allocation sequence generation methods, and only 2.4% mentioned allocation concealment. The vast majority (86.8%) of trials were open-label, while only 13.2% used blinding. Almost half (45.5%) administered the CHM intervention as a tea or decoction. Only one trial (0.6%) reported a sample size calculation, and a single trial (0.6%) discussed quality control of the CHM intervention. CONCLUSION: The overall methodologic quality of RCTs in CHM was poor. It is essential to improve the design of future RCTs in this clinical area. RECOMMENDATIONS: (1) Investigator conducting RCTs should have formal training about clinical trial design; (2) A flow chart is recommended to ensure that all essential steps of clinical trial design are included. (3) Conducting pilot studies prior to RCTs may help improve their design; (4) Registration of clinical trials and publishing their protocols prior to enrollment may reduce publication bias and solicit peer reviews of the proposed design; (5) Collaboration between CHM investigators and traditional medicine academic research centers interested in integrative medicine may lead to quality improvement of RCTs of CHM.

Humans↗
PubMed2006

Improving the quality of randomized controlled trials in Chinese herbal medicine, part II: control group design.

OBJECTIVE: To discuss the types of control groups in randomized controlled trials (RCTs) of Chinese herbal medicine (CHM), and to provide suggestions for improving the design of control group in future clinical studies in this therapeutic area. METHODS: A search of the Cochrane Library was conducted in July 2005 to identify RCTs of CHM, and 66 RCTs with CHM for type 2 diabetes mellitus were obtained as the basis for further analysis. RESULTS: Of 66 RCTs with CHM for type 2 diabetes mellitus, 61 (92.4%) trials had both a treatment group and a control group. Twenty-seven (40.9%) RCTs compared CHM plus conventional drug vs conventional drug, 24 (36.4%) compared CHM vs conventional drug, 5 (7.6%) compared CHM vs placebo, 3 (4.5%) compared CHM plus conventional drug vs conventional drug plus placebo, 3 (4.5%) compared CHM plus conventional drug vs other CHM, 1 (1.5%) compared CHM vs no treatment, 1 (1.5%) compared CHM plus placebo vs conventional drug plus placebo, 1 (1.5%) compared CHM vs CHM plus conventional drug vs conventional drug vs placebo, and 1 (1.5%) compared CHM vs conventional drug vs CHM plus conventional drug. CONCLUSION: A variety of control groups were used in RCTs of CHM for type 2 diabetes mellitus, including placebo, active, and no treatment control groups. Justification for selecting particular types of control groups were not provided in the trials reviewed in this study. Different control groups may be appropriate according to the study objectives, and several factors should be considered prior to selecting control groups in future RCTs of CHM. RECOMMENDATIONS: (1) Investigators of CHM who design clinical trials should understand the rationale for selecting different types of control groups; (2) Control groups for RCTs should be selected according to study objectives; (3) Active control groups should select interventions for comparisons that have the strongest evidence of efficacy and prescribe them as recommended; (4) Placebo control groups should select a placebo that mimics the physical characteristics of test intervention as closely as possible and is completely inert; (5) No treatment control groups should only be used when withholding treatment is ethical and objectives outcomes will not be subject to bias due to absent blinding; (6) Crossover control groups may be appropriate in chronic and stable conditions.

Control Groups↗
PubMed2006

Improving the quality of randomized controlled trials in Chinese herbal medicine, part III: quality control of Chinese herbal medicine used in randomized controlled trials.

OBJECTIVE: To discuss quality control of Chinese herbal medicine (CHM) in randomized controlled trials (RCTs), and to provide suggestions for improving this aspect in future clinical study in this therapeutic area. METHODS: A search of the Cochrane Library was conducted to identify RCTs of CHM. Quality control information reported in those RCTs was then assessed independently. RESULTS: The search yielded a total of 167 RCTs of CHM for a variety of conditions. A total of 11 CHM preparations were used in those RCTs. Only one trial discussed quality control of the CHM interventions used. Issues affecting the safety and efficacy of CHM products used in RCTs were discussed including standardization of raw herbal materials, processing methods, screening for product contamination, and effects of combination products. CONCLUSION: The overall quality of reporting of RCTs of CHM was poor, reflecting the need for improvements in reporting future clinical trials in this area. RECOMMENDATIONS: To improve quality control of CHM used in RCTs in future, we recommend developing and implementing guidelines such as Good Agricultural Practice (GAP) for Chinese crude drugs, and current Good Manufacturing Practice (GMP) specific to CHM products. Chemical analyses of individual herbs of CHM and combination products are also recommended to provide reference standards for quality control.

Drugs, Chinese Herbal↗
PubMed2006

Improving the quality of randomized controlled trials in Chinese herbal medicine, part IV: applying a revised CONSORT checklist to measure reporting quality.

OBJECTIVE: To discuss the quality of reporting in randomized controlled trials (RCTs) of Chinese herbal medicine (CHM), and to provide suggestions for improving the reporting of future clinical studies in this therapeutic area. METHODS: A search of the Cochrane Library was conducted to identify RCTs of CHM. A revised CONSORT checklist designed for CHM clinical studies was implemented. The revised CONSORT checklist contained 63 items, including the following new items added specifically for CHM: (1) "syndrome of disease" based on Chinese medicine theories; (2) rationale of CHM formula; (3) formula composition; (4) preparation form of CHM; (5) quality control of CHM. RESULTS: The overall reporting quality of the RCTs as assessed with the revised CONSORT checklist varied between 19% and 44%, with a median score of 32% (standard deviation 8%). CONCLUSION: The overall quality of reporting of RCTs of CHM evaluated with a revised CONSORT checklist was poor, reflecting the need for improvements in reporting future clinical trials in this area. RECOMMENDATIONS: To improve the quality of reporting of RCTs of CHM, we recommend adopting a revised CONSORT checklist that includes items specific to CHM. We also recommend that editors of CHM journals require authors to use a structured approach to presenting their trials as a condition of publication.

Drugs, Chinese Herbal↗