Allocation concealment in randomised controlled trials: are we getting better?: Table 1

Clark, Laura; Fairhurst, Caroline; Torgerson, David

doi:10.1136/bmj.i5663

Cited by 50 publications

(44 citation statements)

References 24 publications

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“…Similar to blinding, allocation concealment is an important element to control bias in a clinical trial. A study examining a sample of RCTs published in major medical journals in 2015 found that nearly 40% of these studies did not report satisfactory methods for allocation concealment (40). However, improvements have been noted as far as reporting trends are concerned.…”

Section: Discussionmentioning

confidence: 99%

Methodological Characteristics of Clinical Trials: Impact of Mandatory Trial Registration

et al. 2019

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Purpose: Numerous studies across multiple specialties have evaluated the impact of trial registration on quality of study reports and found significant improvements over several domains. However, the impact of mandatory trial registration on the quality of clinical trial protocols remains hitherto unexplored. Methods: We carried out a retrospective cohort study of clinical trial applications submitted to drug regulatory authority of India for initial review with the objective of comparing methodological characteristics of their protocols. Since trial registration was made mandatory in the country in June 2009, we selected two study periods as between January 2007 to May 2009 (Period I) and July 2009 to December 2011 (Period II). Seventy-five protocols were randomly selected using a computer-generated list for each study period, making a total of 150 protocols. Data on twelve key methodological characteristics were collected including clearly defined primary outcomes, randomization, blinding, use of control group, statistical methods, handling of withdrawals amongst others. Results: More than 3/4th of the trial applications in the two study periods were for new chemical entities and nearly 90% were pharmaceutical industry sponsored studies. Comparing the period before and after implementation of mandatory trial registration, description of clearly defined trial outcomes improved from nearly 42% to 80% (p<0.001), sample size justifications increased from 38% to 70% (p<0.001) and use of allocation concealment improved from 24% to 49% (p=0.001). Marked improvement was also noted for blinding, description of statistical methods and handling of withdrawals and dropouts. Remaining characteristics did not change significantly between the two study periods. The mean cumulative scores for the study protocols improved significantly from 7± 0.296 in the first period to 8.93± 0.346 (p<0.001) in the second period. Conclusions: Our study found a significant improvement in the methodological quality characteristics of the protocols particularly in elements related to minimization of bias and statistical methods, which could be attributed to mandatory trial registration. Overall, the significant improvement was limited to global clinical trials, and room for improvement was noted for two quality characteristics – proportion of randomized studies and trials adequately describing the generation of allocation sequence.

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Section: Discussionmentioning

confidence: 99%

Methodological Characteristics of Clinical Trials: Impact of Mandatory Trial Registration

et al. 2019

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“…The randomisation permits the use of the probability theory to express the likelihood of chance as a source for the differences of an outcome . The allocation concealment refers to separate the act of randomisation from the person recruiting participants and is dependent on the method of sequence generation, as well as, the concealment mechanism . A total of seven out of the ten studies described clearly the randomisation and allocation concealment in this systematic review .…”

Section: Discussionmentioning

confidence: 99%

Effect of ibuprofen on the efficacy of inferior alveolar nerve block in patients with irreversible pulpitis: A meta‐analysis

et al. 2018

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Keywords ibuprofen, inferior alveolar nerve block, irreversible pulpitis, meta-analysis, systematic review. AbstractThe aim of this study was to compare preventive ibuprofen administration to placebo on the efficacy of inferior alveolar nerve block in patients with irreversible pulpitis. A search was performed in PubMed, Scopus, Web of Science, LILACS, BBO, Cochrane Library, SIGLE, and grey literature. The risk of bias was evaluated through the Cochrane Collaboration's tool. The quality of evidence was assessed using the GRADE approach. Only seven studies remained for the meta-analysis. Administering ibuprofen before anaesthesia increased the success rate of injectable anaesthesia (RR = 1.79; 95% confidence interval (CI) 1.32-2.42; P = 0.0002) even in cases of symptomatic irreversible pulpitis (RR = 1.55; 95% CI 1.05-2.29; P = 0.03). The intensity of pain was lower for ibuprofen (standardised difference means (SMD) = À3.73; 95% CI À6.43 to À1.04; P = 0.007). Ibuprofen as premedication is beneficial for the success of inferior alveolar nerve block.

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“…Fifty patients were randomly allocated into experimental and control groups (25 patients each) using the sequentially numbered, opaque sealed envelopes method. Where envelopes containing the treatment allocation were opened by the recruiting physician (Clark et al, 2016).…”

Section: Methodsmentioning

confidence: 99%

Assessment of Intravenous Lipid Emulsion as an Adjuvant Therapy in Acute Aluminum Phosphide Poisoning: A randomized Controlled Trial

ELabdeen

Saad

Oreby

et al. 2020

Ain Shams Journal of Forensic Medicine and Clinical Toxicology

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Background: Aluminum phosphide (ALP) is efficient rodenticide and insecticide. The increased incidence of acute ALP poisoning and its high mortality is a challenge for health professionals, there is no specific antidote and the treatment is mainly supportive. Aim of the work: The aim of this study was to evaluate the efficacy and safety of intravenous lipid emulsion as an adjuvant therapy for acute ALP poisoning. Patients and methods: The present study was carried out on fifty patients with acute ALP poisoning admitted at Poison Control Unit, Tanta University Emergency Hospital, throughout a period from the start of December 2016 till November 2017. The study participants were randomly allocated into 2 equal groups (25 patients each): The experimental group (received ILE 20% at a rate of 10ml/h IV infusion plus the conventional treatment of ALP poisoning), and the control group (received the conventional treatment only). Results: The number of deaths in the experimental group was lower than the control group, but it did not reach a significant level. The need for intubation and mechanical ventilation was significantly lower in the experimental group compared to the control group. Conclusion: The administration of ILE 20% in acute ALP poisoning at a rate of 10ml/h IV infusion is a safe therapy. Moreover, the adjuvant ILE use along with the conventional supportive treatment could have a therapeutic effect in ALP poisoned patients.

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Allocation concealment in randomised controlled trials: are we getting better?: Table 1

Abstract: Laura Clark and colleagues assess the allocation concealment methods in a sample of randomised controlled trial publications

Cited by 50 publications

References 24 publications

Methodological Characteristics of Clinical Trials: Impact of Mandatory Trial Registration

Methodological Characteristics of Clinical Trials: Impact of Mandatory Trial Registration

Effect of ibuprofen on the efficacy of inferior alveolar nerve block in patients with irreversible pulpitis: A meta‐analysis

Assessment of Intravenous Lipid Emulsion as an Adjuvant Therapy in Acute Aluminum Phosphide Poisoning: A randomized Controlled Trial

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