Time to onset of cannabidiol treatment effects in Dravet syndrome: Analysis from two randomized controlled trials

The most reliable information about treatment effects comes from randomized controlled trials (RCTs). However, the possibility of subtle interactions—for example, between treatment preferences and treatment effects—is generally subordinated in the quest for evidence about main treatment effects. If patient preferences can influence the effectiveness of treatments through poorly understood (psychological) pathways, then RCTs, particularly when unblinded, may wrongly attribute effects solely to a treatment's physiological/pharmacological properties. To interpret the RCT evidence base it is important to know whether any preference effects exist and, if so, by how much they affect outcome. Reliable measurement of these effects is difficult and will require new approaches to the conduct of trials. In view of the fanciful image with which such effects are portrayed and the uncertainties about their true nature and biological mechanisms, existing evidence is unlikely to provide sufficient justification for investment in trials. This is a Catch 22. Until an escape is found we might never know, even approximately, how much of modern medicine is attributable to psychological processes.

Download Full-text

Rigorous control conditions diminish treatment effects in weight loss-randomized controlled trials

International Journal of Obesity ◽

10.1038/ijo.2015.212 ◽

2015 ◽

Vol 40 (6) ◽

pp. 895-898 ◽

Cited By ~ 5

Author(s):

J A Dawson ◽

K A Kaiser ◽

O Affuso ◽

G R Cutter ◽

D B Allison

Keyword(s):

Weight Loss ◽

Randomized Controlled Trials ◽

Treatment Effects ◽

Controlled Trials ◽

Randomized Controlled

Download Full-text

Between-centre differences and treatment effects in randomized controlled trials: A case study in traumatic brain injury

Trials ◽

10.1186/1745-6215-12-201 ◽

2011 ◽

Vol 12 (1) ◽

Cited By ~ 20

Author(s):

Hester F Lingsma ◽

Bob Roozenbeek ◽

Pablo Perel ◽

Ian Roberts ◽

Andrew IR Maas ◽

...

Keyword(s):

Traumatic Brain Injury ◽

Brain Injury ◽

Randomized Controlled Trials ◽

Treatment Effects ◽

Controlled Trials ◽

Randomized Controlled

Download Full-text

Mindfulness Enhances Cognitive Functioning: A Meta-Analysis of 95 Randomized Controlled Trials

10.31234/osf.io/vzxw7 ◽

2020 ◽

Author(s):

Nur Hani Hani Zainal ◽

Michelle G. Newman

Keyword(s):

Randomized Controlled Trials ◽

Sustained Attention ◽

Treatment Effects ◽

Control Group ◽

Controlled Trials ◽

Cognitive Domains ◽

Positive Effects ◽

Mindfulness Skills ◽

Randomized Controlled ◽

The Impact

Background: The past 30 years have witnessed growing scientific interest regarding the impact of mindfulness-based interventions (MBIs) on cognitive functions. Several theories propose that habitually exercising mindfulness skills can improve cognitive abilities, but no comprehensive quantitative reviews of the effect of MBIs on global and unique cognitive domains exist to date. Method: This systematic review thus examined the effects of MBI on global cognitive ability (GCA) and 16 specific cognitive domains. MBI randomized controlled trials (RCTs) that administered cognitive tests pre- and post-treatment were included. Open-trials, non-randomized MBIs, and case-control studies were excluded. Keywords included “mindful*,” AND “executive attention (EA),” OR “working memory (WM).” Robust variance estimation and moderator analyses were conducted. Results: Ninety-five RCTs (n = 7,408) met eligibility criteria. MBI (vs. waitlist or no-treatment) had small-to-moderate significant effects on GCA, WM accuracy, inhibition accuracy and latency, EA, sustained attention accuracy, processing speed, and subjective attentional control (SAC) (g = 0.24 – 0.52). Likewise, MBI (vs. active control) had small-to-moderate positive effects on GCA, orienting, EA, WM accuracy, sustained attention (indexed by intra-individual coefficient of variation), and SAC (average g = 0.17 – 0.41). Age, gender, study quality, treatment duration, publication year, retention, statistical analysis, and country, moderated some treatment effects. Publication bias analyses showed that reliable treatment effects were restricted to EA, WM accuracy, inhibition accuracy, sustained attention, and SAC, depending on the control group. Conclusion: MBIs confer notable neuropsychological benefits and dose-response effects on some specific (vs. global) cognitive domains. Limitations, theoretical, and applied implications are discussed. (NOTE: This paper has not been peer reviewed. Please do not copy or cite without author's permission.)

Download Full-text

Impact of risk of bias on the magnitude of treatment effects of randomized controlled trials in implant dentistry

10.21203/rs.3.rs-41578/v1 ◽

2020 ◽

Author(s):

Ruolin Ding ◽

Wenxin Lu ◽

Jianru Yi ◽

Liang Zhang ◽

Zhihe Zhao

Keyword(s):

Randomized Controlled Trials ◽

Treatment Effects ◽

Permutation Test ◽

Random Sequence ◽

Allocation Concealment ◽

Risk Of Bias ◽

Selective Reporting ◽

Controlled Trials ◽

Randomized Controlled ◽

Implant Dentistry

Abstract Background: Risk of bias (RoB) could influence the magnitude of treatment effects of randomized controlled trials (RCTs). This study aims to investigate the potential influence of RoB on treatment effects estimates in RCTs in implant dentistry. Methods: The RCTs published in five leading oral implant journals during the recent five years were electronically searched. The RoB was assessed using the Cochrane Collaboration RoB tool. The meta-regression analysis and Monte Carlo permutation test were performed to identify the association between RoB and the magnitude of treatment effects.Results: A considerable amount of studies have high RoB in blinding of participants and personnel, and unclear RoB in allocation concealment and selective reporting. The treatment effects were exaggerated by flaws in allocation concealment for binary outcomes and by deficiencies in random sequence generation and selective reporting for continuous outcomes.Conclusion: RoB frequently exists in RCTs recently published in implant dentistry, which may lead to the exaggeration of treatment effects. Better study design, implementation, and reporting are required for clinical trials in implant dentistry to ensure more reliable evidence.

Download Full-text

Intensive versus Usual Control of Hypertension in the Prevention of Cardiovascular and Renal Outcomes: A Cumulative Meta-Analysis of Randomized Controlled Trials

Kidney & Blood Pressure Research ◽

10.1159/000499009 ◽

2019 ◽

Vol 44 (3) ◽

pp. 384-395 ◽

Cited By ~ 2

Author(s):

Li Li ◽

Ling Li

Keyword(s):

Myocardial Infarction ◽

Randomized Controlled Trials ◽

Cardiac Death ◽

Cardiovascular Events ◽

Treatment Effects ◽

Meta Analysis ◽

Controlled Trials ◽

Renal Outcomes ◽

Randomized Controlled ◽

Major Cardiovascular Events

Background/Aims: Previous studies have reported inconsistent results regarding the treatment effects of intensive blood pressure (IBP) control in the prevention of cardiovascular and renal outcomes. We conducted this cumulative meta-analysis to evaluate the treatment effects of IBP control on cardiovascular and renal outcomes. Methods: We systematically searched PubMed, EMBASE, and the Cochrane Library databases from the date of their inception to October 2017, to identify randomized controlled trials (RCTs). The relative risks (RRs) with corresponding 95% confidence intervals (CIs) were used to evaluate the treatment effects of IBP control by using a random-effects model. Results: The final analysis included 20 RCTs involving 56,687 individuals. The summary RRs indicated that IBP control treatment significantly reduced the risk of major cardiovascular events (RR: 0.85; 95% CI: 0.77–0.94; p = 0.001), including myocardial infarction (RR: 0.87; 95% CI: 0.76–1.00; p = 0.044), stroke (RR: 0.77; 95% CI: 0.66–0.89; p < 0.001), and albuminuria (RR: 0.90; 95% CI: 0.84–0.97; p = 0.007). However, IBP control had no significant effect on heart failure (RR: 0.80; 95% CI: 0.62–1.03; p = 0.077), all-cause mortality (RR: 0.91; 95% CI: 0.81–1.02; p = 0.112), cardiac death (RR: 0.91; 95% CI: 0.75–1.12; p = 0.390), non-cardiac death (RR: 0.98; 95% CI: 0.86–1.12; p = 0.773), end-stage renal disease (RR: 0.90; 95% CI: 0.77–1.06; p = 0.203), and retinopathy (RR: 0.81; 95% CI: 0.66–1.00; p = 0.052). Conclusion: The findings of this study suggest that IBP control plays a beneficial role in the prevention of some major cardiovascular events, including myocardial infarction, stroke, and albuminuria.

Download Full-text

Predicting response to topical non-steroidal anti-inflammatory drugs in osteoarthritis: an individual patient data meta-analysis of randomized controlled trials

Rheumatology ◽

10.1093/rheumatology/keaa113 ◽

2020 ◽

Vol 59 (9) ◽

pp. 2207-2216 ◽

Cited By ~ 4

Author(s):

Monica S M Persson ◽

Joanne Stocks ◽

Gyula Varadi ◽

Mohammad Hashem Hashempur ◽

Marienke van Middelkoop ◽

...

Keyword(s):

Pain Relief ◽

Randomized Controlled Trials ◽

Treatment Effects ◽

Individual Patient Data ◽

Meta Analysis ◽

Specific Effect ◽

Patient Data ◽

Controlled Trials ◽

Randomized Controlled ◽

Topical Nsaids

Abstract Objectives To identify predictors of the specific (difference between treatment and placebo) and overall (change from baseline in treatment arm) treatment effects of topical NSAIDs in OA. Methods Randomized controlled trials (RCTs) of topical NSAIDs in OA were identified through systematic literature searching and inquiry to pharmaceutical companies. The raw, de-identified data were analysed in one-stage individual patient data meta-analysis (IPD-MA). Negative values for treatment effects (0–100 scale) indicate pain reduction. Results Of 63 eligible RCTs, 15 provided IPD (n = 1951 on topical NSAID), including 11 placebo-controlled RCTs (n = 1587 on topical NSAIDs, 1553 on placebo). Seven potential predictors of response were examined. Topical NSAIDs were superior to placebo [−6 (95% CI −9, −4)], with a small, but statistically significant greater effect in women than men [difference −4 (95% CI −8, −1)]. The overall treatment effect was 4-fold larger than the specific effect [−25 (95% CI −31, −19)] and increased with greater baseline pain severity (P < 0.001). No differences in efficacy were observed for age, BMI, features of inflammation, duration of complaints or radiographic OA severity. Conclusion Topical NSAIDs are effective for OA pain relief. Greater overall pain relief in individuals with more baseline pain might be due to contextual and non-specific effects, including regression to the mean. Additional factors that have been linked either mechanistically or through empirical evidence to outcomes should be selected for inclusion across future RCTs in order to facilitate the identification of response predictors through IPD-MA.

Download Full-text