scholarly journals How reliable are randomised controlled trials for studying the relationship between diet and disease? A narrative review

2016 ◽  
Vol 116 (3) ◽  
pp. 381-389 ◽  
Author(s):  
Norman J. Temple
Keyword(s):  
Cohort Studies ◽  
Randomised Controlled Trials ◽  
Critical Evaluation ◽  
Epidemiological Studies ◽  
Dietary Factors ◽  
Controlled Trials ◽  
Large Numbers ◽  
History Of ◽  
Randomised Controlled

AbstractLarge numbers of randomised controlled trials (RCT) have been carried out in order to investigate diet–disease relationships. This article examines eight sets of studies and compares the findings with those from epidemiological studies (cohort studies in seven of the cases). The studies cover the role of dietary factors in blood pressure, body weight, cancer and heart disease. In some cases, the findings from the two types of study are consistent, whereas in other cases the findings appear to be in conflict. A critical evaluation of this evidence suggests factors that may account for conflicting findings. Very often RCT recruit subjects with a history of the disease under study (or at high risk of it) and have a follow-up of only a few weeks or months. Cohort studies, in contrast, typically recruit healthy subjects and have a follow-up of 5–15 years. Owing to these differences, findings from RCT are not necessarily more reliable than those from well-designed prospective cohort studies. We cannot assume that the results of RCT can be freely applied beyond the specific features of the studies.

Efficacy of electronic cigarettes for tobacco smoking cessation: An adapted systematic review

2020 ◽  
Vol 30 (Supplement_5) ◽  
Author(s):  
T O'Dowd
Keyword(s):  
Smoking Cessation ◽  
Cohort Studies ◽  
Randomised Controlled Trials ◽  
Electronic Cigarettes ◽  
Controlled Trials ◽  
Significant Heterogeneity ◽  
Smoking Reduction ◽  
Significant Difference ◽  
Randomised Controlled

Abstract Background Worldwide smoking remains the leading cause of preventable morbidity and mortality. Electronic cigarettes (ECs) are increasingly used by tobacco smokers as an aid to smoking cessation; however, their efficacy remains uncertain. Methods Electronic databases, clinical trial registries and grey literature sources were searched. The aim was to examine randomised controlled trials or prospective cohort studies, published since the 2016 Cochrane review on this topic, that assessed the efficacy of ECs in achieving smoking cessation among current smokers. Results Two RCTs and five cohort studies, including a total of 16,460 participants, were eligible for inclusion. One RCT found sustained 1-year abstinence of 18.0% in the EC group versus 9.9% in the nicotine replacement therapy group (RR: 1.83; 95% CI 1.30 to 2.58; P < 0.001). The second RCT did not find a statistically significant difference in abstinence rates between EC users and non-users (RR 0.71). Of the five included cohort studies, four reported statistically significant RRs. Two found a positive association (RRs of 1.45 and 1.84) between EC use and smoking cessation but two studies showed EC use was associated with reduced smoking cessation (RRs of 0.25 and 0.35). Due to significant heterogeneity between the studies the data were deemed unsuitable for pooling into a meta-analysis. All trials assessing smoking reduction reported higher rates of reduction among EC users. No serious adverse events were reported with EC use. Follow-up periods of included trials ranged from one to four years, with an average of 1.6 years. Conclusions There is limited, low-quality evidence that ECs are an effective intervention for smoking cessation and smoking reduction. The overall quality of evidence is low as it is based on a small number of studies with inconsistent and imprecise results. Due to the short follow-up periods of the included trials, the long-term safety of ECs is unclear from this review. Key messages Limited evidence that electronic cigarettes are an effective smoking cessation intervention. Further well-designed randomised controlled trials are required to investigate the efficacy of ECs for smoking cessation.

scholarly journals Potential impact on estimated treatment effects of information lost to follow-up in randomised controlled trials (LOST-IT): systematic review

BMJ ◽  
2012 ◽  
Vol 344 (may18 1) ◽  
pp. e2809-e2809 ◽  
Author(s):  
E. A. Akl ◽  
M. Briel ◽  
J. J. You ◽  
X. Sun ◽  
B. C. Johnston ◽  
...  
Keyword(s):  
Systematic Review ◽  
Randomised Controlled Trials ◽  
Treatment Effects ◽  
Controlled Trials ◽  
Potential Impact ◽  
Randomised Controlled ◽  
Lost To Follow Up

Seksueel onaangepast gedrag bij een patiënt met dementie: literatuurreview en casusrapport

2021 ◽  
Author(s):  
C. SEAUX ◽  
K. GOEDSEELS ◽  
J. DE LEPELEIRE
Keyword(s):  
Case Studies ◽  
Randomised Controlled Trials ◽  
Selective Serotonin Reuptake Inhibitors ◽  
Controlled Trials ◽  
Pharmacological Treatments ◽  
Pharmacological Interventions ◽  
Drug Of Choice ◽  
Cochrane Database ◽  
History Of ◽  
Randomised Controlled

Sexually inappropriate behaviour in a patient with dementia: literature review and case report In this paper, the medical history of a 75-year-old man with dementia and sexually inappropriate behaviour (SIB) is described. An overview of the literature regarding the approach and treatment of SIB in persons with dementia was performed. PubMed, Web of Science and the Cochrane database were consulted, and thirteen articles selected. There are no randomised controlled trials available. The literature is limited to case studies and reviews of case studies. Non-pharmacological treatments are perceived to be the first step, although they are rarely studied. There is no consensus regarding a pharmacological approach. However, all studies suggest the paradigm of “start low and go slow”. A variety of drugs have been described. When starting a pharmacological treatment, it is recommended to keep in mind comorbidities and possible side-effects. Selective serotonin reuptake inhibitors (SSRIs) seem to be the preferred first line treatment if the behaviour is not too harmful. If the behaviour is intrusive, anti-androgens seem to be the drug of choice. Further research is needed: a consensus regarding the definition and the development of a screening tool could support randomised controlled trials concerning pharmacological and non-pharmacological interventions. Research concerning ethical dilemmas should, however, not be neglected.

scholarly journals The impact of a run-in period on treatment effects in cardiovascular prevention randomised control trials: A protocol for a comprehensive review and meta-analysis

2020 ◽  
Vol 3 ◽  
pp. 82
Author(s):  
Robert Murphy ◽  
Emer McGrath ◽  
Aoife Nolan ◽  
Andrew Smyth ◽  
Michelle Canavan ◽  
...  
Keyword(s):  
Randomised Controlled Trials ◽  
Treatment Effects ◽  
Meta Analysis ◽  
Cardiovascular Prevention ◽  
Controlled Trials ◽  
Loss To Follow Up ◽  
Relative Risks ◽  
Prevention Trials ◽  
Randomised Controlled

Background: A run-in period is often employed in randomised controlled trials to increase adherence to the intervention and reduce participant loss to follow-up in the trial population. However, it is uncertain whether use of a run-in period affects the magnitude of treatment effect. Methods: We will conduct a sensitive search for systematic reviews of cardiovascular preventative trials and a complete meta-analysis of treatment effects comparing cardiovascular prevention trials using a run-in period (“run-in trials”) with matched cardiovascular prevention trials that did not use a run-in period (“non-run-in trials”). We describe a comprehensive matching process which will match run-in trials with non-run-in trials by patient populations, interventions, and outcomes. For each pair of run-in trial and matched non-run-in trial(s), we will estimate the ratio of relative risks and 95% confidence interval. We will evaluate differences in treatment effect between run-in and non-run-in trials and our and our priamry outcome will be the ratio of relative risks for matched run-in and non-run-in trials for their reported cardiovascular composite outcome. Our secondary outcomes are comparisons of mortality, loss to follow up, frequency of adverse events and methodological quality of trials. Conclusions: This study will answer a key question about what influence a run-in period has on the magnitude of treatment effects in randomised controlled trials for cardiovascular prevention therapies.

Effect of action observation therapy on motor function in children with cerebral palsy: a systematic review of randomized controlled trials with meta-analysis

2020 ◽  
pp. 026921552095434
Author(s):  
Naglaa Abdelhaleem ◽  
Samar Taher ◽  
Menna Mahmoud ◽  
Ahmad Hendawy ◽  
Maged Hamed ◽  
...  
Keyword(s):  
Cerebral Palsy ◽  
Methodological Quality ◽  
Randomised Controlled Trials ◽  
Action Observation ◽  
Meta Analysis ◽  
Post Treatment ◽  
Controlled Trials ◽  
Children With Cerebral Palsy ◽  
Randomised Controlled

Objective: To evaluate the evidence of using Action Observation Therapy in the rehabilitation of children with Cerebral Palsy. Study design: Systematic review with meta-analysis of Randomised Controlled Trials. Methods: For the purpose of identifying relevant studies, six databases were searched from inception until July 2020. The methodological quality was assessed by Physiotherapy Evidence Database scale. The outcomes were classified within the framework of the International Classification of Functioning. A pooled meta-analysis was performed on studies that demonstrated homogeneity. Results: Twelve randomised controlled trials with 307 participants were included with six of them were included in the meta-analysis. Non-significant difference between the groups was demonstrated by meta-analysis. Results of capacity assessed in post treatment and follow up evaluation were (0.06, –0.22 to 0.34, 95% (CI); P = 0.69 and (–0.35, –0.96 to 0.27, 95% (CI); P = 0.27); respectively. Actual performance in post-treatment and follow up were (0.10, –0.22 to 0.48, 95% (CI); P = 0.62) and (0.01, –0.40 to 0.41, 95% (CI); P = 0.97); respectively. Perceived performance evaluated using (ABILHAND-KIDS) were (0.30, –0.28 to 0.89, 95% (CI); P = 0.31) and (0.15, –0.43 to 0.73, 95% (CI); P = 0.61) for post treatment and follow up; respectively. Overall effect on activity domain was (0.08, –0.11 to 0.28, 95% (CI); P = 0.86) immediately and (0.04, –0.33 to 0.26, 95% (CI); P = 0.49) at follow-up; respectively. Conclusion: No evidence of benefit had been found to draw a firm conclusion regarding the effectiveness of action observation therapy in the rehabilitation of children with cerebral palsy due to limitations in methodological quality and variations between studies.

scholarly journals Protective effects of dietary PUFA against chronic disease: evidence from epidemiological studies and intervention trials

2013 ◽  
Vol 73 (1) ◽  
pp. 73-79 ◽  
Author(s):  
Thomas A. B. Sanders
Keyword(s):  
Chronic Disease ◽  
Cohort Studies ◽  
Cardiac Death ◽  
Lower Risk ◽  
Randomised Controlled Trials ◽  
Cochrane Review ◽  
Total Mortality ◽  
Partial Replacement ◽  
Controlled Trials ◽  
Randomised Controlled

This review considers evidence for a protective effect of PUFA on chronic disease. Estimates of PUFA intakes in prospective cohort studies are usually based on FFQ or biomarkers of intake. Cohort studies suggest that both linoleic and linolenic acid intake are associated with a lower risk of CHD. The intake of fish, the major source of long-chainn-3 PUFA is associated with a lower risk of both stroke and CHD, particularly sudden cardiac death. No relationship with common sites of cancer (breast and colon) and PUFA has been found. However, some recent studies suggest an association of high intakes ofn-3 PUFA with risk of prostate cancer. An updated Cochrane review of dietary fat modification (replacing SFA with PUFA) randomised controlled trials to prevent CHD found a 14 % lower incidence and a non-significant 7 % lower mortality from CHD. The effects of an increased intake ofn-3 PUFA on CHD incidence mortality have been tested in patients with pre-existing CHD in randomised controlled trials. Meta-analysis of these trials showed no overall benefit on total mortality or CVD incidence but a trend for lower risk of cardiac death was 0·91 (95 % CI 0·85, 0·98). At present, there is little evidence from other trials demonstrating the clear benefits or harm from increased intakes of PUFA. In conclusion, present evidence intakes benefit from partial replacement of SFA with a balanced mixture ofn-6 andn-3 PUFA which may contribute to CVD prevention.

Acupuncture Studies on Pain

1997 ◽  
Vol 15 (1) ◽  
pp. 23-31 ◽  
Author(s):  
Moolamanil Thomas
Keyword(s):  
Chronic Pain ◽  
Randomised Controlled Trials ◽  
Sensory Stimulation ◽  
Complementary Therapy ◽  
Controlled Trials ◽  
Clinical Use ◽  
Basic Understanding ◽  
History Of ◽  
Randomised Controlled ◽  
Peripheral Sensory

The relegation of acupuncture to complementary therapy ignores the history of its development and restricts possibilities for its clinical use and further research. Clinical studies with randomised, controlled trials and double blinding require reconsideration and adaptation when using acupuncture for treatment when multiple patient and treatment variables are involved. Ample experimental evidence exists for acupuncture to be considered as a modality of peripheral sensory stimulation, but present clinical research has not incontrovertibly validated the use of acupuncture on patients with chronic pain. A basic understanding of the neuro-physiology of pain and its differentiation does provide better indications for its use. More consistent results may then be obtained, as seen from a few recent studies.

Who Benefits from Electroconvulsive Therapy?

1992 ◽  
Vol 160 (3) ◽  
pp. 355-359 ◽  
Author(s):  
Heather Buchan ◽  
Eve Johnstone ◽  
K. McPherson ◽  
R. L. Palmer ◽  
T. J. Crow ◽  
...  
Keyword(s):  
Electroconvulsive Therapy ◽  
Treatment Effect ◽  
Randomised Controlled Trials ◽  
Controlled Trials ◽  
Combining Data ◽  
Randomised Controlled ◽  
Improved Outcome

This paper describes the results obtained by combining data from the Northwick Park and Leicester randomised controlled trials of ECT. Patients who suffered from depression in which retardation and delusions were features and who received real ECT had a significantly improved outcome at the end of four weeks of treatment (as measured by improvement in the HRSD) in comparison with those who received simulated ECT. However, this treatment effect was not detectable at six-month follow-up. Patients who were neither retarded nor deluded did not benefit significantly from real as opposed to simulated ECT.

scholarly journals Incidence and prognostic factors of knee extension deficits following anterior cruciate ligament reconstruction: A systematic review and meta-analysis of randomised controlled trials

2020 ◽  
Author(s):  
Nalan Ektas ◽  
Corey Scholes ◽  
Meredith Harrison-Brown ◽  
Maha Jegatheesan ◽  
Ashwin Rajesh ◽  
...  
Keyword(s):  
Prognostic Factors ◽  
Randomised Controlled Trials ◽  
Acl Injury ◽  
Knee Extension ◽  
Cochrane Library ◽  
Controlled Trials ◽  
Extension Deficit ◽  
Eligibility Criteria ◽  
Randomised Controlled

ABSTRACTBackground and aimsKnee extension deficits complicate recovery from ACL injury and reconstruction, however the incidence of knee extension loss is not well defined. The aim of this review was to identify the incidence of loss of extension (LOE) following ACL rupture and reconstruction, explore the definitions of knee extension deficits reported and identify prognostic factors affecting LOE incidence.Methods and analysisA systematic search was conducted in Medline, Cochrane Library and PEDro for studies in publication up to September 2019, with no restrictions on publication year. References were screened and assessed for inclusion using predetermined eligibility criteria. Randomised controlled trials (RCTs) that quantified knee angle, loss of extension or incidence of extension deficit were included for quality assessment and data extraction. Statistical summaries were generated and meta-analyses performed in two parts to examine: (i) the probability of a datapoint being zero incidence compared to a non-zero incidence, and (ii) the relationship between the predictors and non-zero LOE incidence.ResultsA sample of 8594 papers were retrieved using the search criteria, with 48 studies meeting eligibility criteria. Pooled results from 4065 participants were included for analysis, with 3965 participants who had undergone ACLR. The proportion of included studies judged at an overall low risk of bias was small (6%). The analysis revealed median LOE incidence of 15.9% (IQR 1.4 - 46.5) at a median follow up from treatment of 4.9 months (IQR 1.9 - 24). Median LOE incidence was 23 % (IQR 8.4 - 50.0) for the subset of studies reporting up to 12 months of follow up. The observed group and study were the most important predictors for whether a datapoint reported an incidence of extension deficit. Time to follow up (P < 0.001) and graft type (P = 0.02) were found to have a significant influence on non-zero LOE incidence (%).ConclusionsThis review examined the definitions for the measurement and interpretation of postoperative knee extension, and established the trajectory of knee extension deficit after ACL injury and reconstruction. While factors associated with loss of extension were identified, the trajectory of knee extension deficits were difficult to infer due to discrepancies in measurement techniques and patient variation. Clinicians should expect up to 1 in 3 patients to present postoperatively with loss of extension of at least 3 degrees, which may partially resolve over time. Future work should focus on the development of a standardised framework for postoperative measurement and reporting of LOE.

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