Causes for retraction in the biomedical literature: a systematic review of studies of retraction notices

Background: Many studies have evaluated the prevalence of different reasons for retraction in samples of retraction notices. We aimed to perform a systematic review of such empirical studies of retraction causes.  Methods: The PubMed/MEDLINE database and the Embase database were searched in June 2023. Eligible studies were those containing sufficient data on the reasons for retraction across samples of examined retracted notices.  Results: A 11,181 potentially eligible items were identified, and 43 studies of retractions were included in this systematic review. Studies limited to retraction notices of a specific subspecialty or country, journal/publication type are emerging since 2015. We noticed that the reasons for retraction are becoming more specific and more diverse. In a meta-analysis of 17 studies focused on different subspecialties, misconduct was responsible for 60% (95% confidence interval [CI], 53–67%) of all retractions while error and publication issues contributed to 17% (95% CI, 12–22%) and 9% (95% CI, 6–13%), respectively. The end year of the retraction period in all included studies and the proportion of misconduct presented a weak positive association (coefficient = 1.3% per year, P = 0.002).  Conclusion: Misconduct seems to be the most frequently recorded reason for retraction across empirical analyses of retraction notices, but other reasons are not negligible. Greater specificity of causes and standardization is needed in retraction notices.</p

The role of metformin as a treatment for neuropsychiatric illness

The role of metformin as a treatment for neuropsychiatric illnes

Causes for retraction in the biomedical literature: a systematic review of studies of retraction notices

Background: Many studies have evaluated the prevalence of different reasons for retraction in samples of retraction notices. We aimed to perform a systematic review of such empirical studies of retraction causes.  Methods: The PubMed/MEDLINE database and the Embase database were searched in June 2023. Eligible studies were those containing sufficient data on the reasons for retraction across samples of examined retracted notices.  Results: A 11,181 potentially eligible items were identified, and 43 studies of retractions were included in this systematic review. Studies limited to retraction notices of a specific subspecialty or country, journal/publication type are emerging since 2015. We noticed that the reasons for retraction are becoming more specific and more diverse. In a meta-analysis of 17 studies focused on different subspecialties, misconduct was responsible for 60% (95% confidence interval [CI], 53–67%) of all retractions while error and publication issues contributed to 17% (95% CI, 12–22%) and 9% (95% CI, 6–13%), respectively. The end year of the retraction period in all included studies and the proportion of misconduct presented a weak positive association (coefficient = 1.3% per year, P = 0.002).  Conclusion: Misconduct seems to be the most frequently recorded reason for retraction across empirical analyses of retraction notices, but other reasons are not negligible. Greater specificity of causes and standardization is needed in retraction notices.</p

Treatment efficacy of pharmacotherapies for frontotemporal dementia: a network meta-analysis of randomized controlled trials

Background The neuropsychiatric symptoms of frontotemporal dementia (FTD) have a profound negative impact on disease outcomes and care burden. Available pharmacotherapies might be supported by small-scale randomized controlled trials (RCTs); however, clinical recommendations might not be conclusive. Methods We systematically searched several databases from inception to April 30, 2022, for RCTs of drug therapy in patients with FTD and neuropsychiatric symptoms (primary outcome). Secondary outcomes included changes in caregiver stress, daily interactive activities, cognitive function, and acceptability (adverse event or dropout rates). The network meta-analysis (NMA) procedure was performed under the frequency model, showing effect sizes as standardized mean differences (SMD) or odds ratios (OR) with 95% confidence intervals (95% CIs). Results Seven RCTs with 243 participants were included. Compared with placebo, high-dose oxytocin (72 international units) was associated with the greatest improvement in patients' neuropsychiatric symptoms (SMD = −1.17, 95% CIs = −2.25 to −0.08, z = −2.10, p = 0.035). Piracetam significantly worsened neuropsychiatric symptoms (SMD = 3.48, 95% CIs = 1.58 to 5.37, z = 3.60, p Conclusions This study provides the first NMA for clinical recommendation to support the use of high-dose oxytocin and caution regarding the use of piracetam for neuropsychiatric symptoms in patients with FTD.</p

Treatment efficacy of pharmacotherapies for frontotemporal dementia: a network meta-analysis of randomized controlled trials

Background The neuropsychiatric symptoms of frontotemporal dementia (FTD) have a profound negative impact on disease outcomes and care burden. Available pharmacotherapies might be supported by small-scale randomized controlled trials (RCTs); however, clinical recommendations might not be conclusive. Methods We systematically searched several databases from inception to April 30, 2022, for RCTs of drug therapy in patients with FTD and neuropsychiatric symptoms (primary outcome). Secondary outcomes included changes in caregiver stress, daily interactive activities, cognitive function, and acceptability (adverse event or dropout rates). The network meta-analysis (NMA) procedure was performed under the frequency model, showing effect sizes as standardized mean differences (SMD) or odds ratios (OR) with 95% confidence intervals (95% CIs). Results Seven RCTs with 243 participants were included. Compared with placebo, high-dose oxytocin (72 international units) was associated with the greatest improvement in patients' neuropsychiatric symptoms (SMD = −1.17, 95% CIs = −2.25 to −0.08, z = −2.10, p = 0.035). Piracetam significantly worsened neuropsychiatric symptoms (SMD = 3.48, 95% CIs = 1.58 to 5.37, z = 3.60, p Conclusions This study provides the first NMA for clinical recommendation to support the use of high-dose oxytocin and caution regarding the use of piracetam for neuropsychiatric symptoms in patients with FTD.</p

Subjective and objective sleep alterations in medication-naïve children and adolescents with autism spectrum disorder: a systematic review and meta-analysis

Aims This study aimed to summarize the evidence on sleep alterations in medication-naïve children and adolescents with autism spectrum disorder (ASD). Methods We systematically searched PubMed/Medline, Embase and Web of Science databases from inception through March 22, 2021. This study was registered with PROSPERO (CRD42021243881). Any observational study was included that enrolled medication-naïve children and adolescents with ASD and compared objective (actigraphy and polysomnography) or subjective sleep parameters with typically developing (TD) counterparts. We extracted relevant data such as the study design and outcome measures. The methodological quality was assessed through the Newcastle-Ottawa Scale (NOS). A meta-analysis was carried out using the random-effects model by pooling effect sizes as Hedges’ g. To assess publication bias, Egger’s test and p-curve analysis were done. A priori planned meta-regression and subgroup analysis were also performed to identify potential moderators. Results Out of 4277 retrieved references, 16 studies were eligible with 981 ASD patients and 1220 TD individuals. The analysis of objective measures showed that medication-naïve ASD patients had significantly longer sleep latency (Hedges’ g 0.59; 95% confidence interval [95% CI] 0.26 to 0.92), reduced sleep efficiency (Hedges’ g −0.58; 95% CI −0.87 to −0.28), time in bed (Hedges’ g −0.64; 95% CI −1.02 to −0.26) and total sleep time (Hedges’ g −0.64; 95% CI −1.01 to −0.27). The analysis of subjective measures showed that they had more problems in daytime sleepiness (Hedges’ g 0.48; 95% CI 0.26 to 0.71), sleep latency (Hedges’ g 1.15; 95% CI 0.72 to 1.58), initiating and maintaining sleep (Hedges’ g 0.86; 95% CI 0.39 to 1.33) and sleep hyperhidrosis (Hedges’ g 0.48; 95% CI 0.29 to 0.66). Potential publication bias was detected for sleep latency, sleep period time and total sleep time measured by polysomnography. Some sleep alterations were moderated by age, sex and concurrent intellectual disability. The median NOS score was 8 (interquartile range 7.25–8.75). Conclusion We found that medication-naïve children and adolescents with ASD presented significantly more subjective and objective sleep alterations compared to TD and identified possible moderators of these differences. Future research requires an analysis of how these sleep alterations are linked to core symptom severity and comorbid behavioural problems, which would provide an integrated therapeutic intervention for ASD. However, our results should be interpreted in light of the potential publication bias.</p

Subjective and objective sleep alterations in medication-naïve children and adolescents with autism spectrum disorder: a systematic review and meta-analysis

Aims This study aimed to summarize the evidence on sleep alterations in medication-naïve children and adolescents with autism spectrum disorder (ASD). Methods We systematically searched PubMed/Medline, Embase and Web of Science databases from inception through March 22, 2021. This study was registered with PROSPERO (CRD42021243881). Any observational study was included that enrolled medication-naïve children and adolescents with ASD and compared objective (actigraphy and polysomnography) or subjective sleep parameters with typically developing (TD) counterparts. We extracted relevant data such as the study design and outcome measures. The methodological quality was assessed through the Newcastle-Ottawa Scale (NOS). A meta-analysis was carried out using the random-effects model by pooling effect sizes as Hedges’ g. To assess publication bias, Egger’s test and p-curve analysis were done. A priori planned meta-regression and subgroup analysis were also performed to identify potential moderators. Results Out of 4277 retrieved references, 16 studies were eligible with 981 ASD patients and 1220 TD individuals. The analysis of objective measures showed that medication-naïve ASD patients had significantly longer sleep latency (Hedges’ g 0.59; 95% confidence interval [95% CI] 0.26 to 0.92), reduced sleep efficiency (Hedges’ g −0.58; 95% CI −0.87 to −0.28), time in bed (Hedges’ g −0.64; 95% CI −1.02 to −0.26) and total sleep time (Hedges’ g −0.64; 95% CI −1.01 to −0.27). The analysis of subjective measures showed that they had more problems in daytime sleepiness (Hedges’ g 0.48; 95% CI 0.26 to 0.71), sleep latency (Hedges’ g 1.15; 95% CI 0.72 to 1.58), initiating and maintaining sleep (Hedges’ g 0.86; 95% CI 0.39 to 1.33) and sleep hyperhidrosis (Hedges’ g 0.48; 95% CI 0.29 to 0.66). Potential publication bias was detected for sleep latency, sleep period time and total sleep time measured by polysomnography. Some sleep alterations were moderated by age, sex and concurrent intellectual disability. The median NOS score was 8 (interquartile range 7.25–8.75). Conclusion We found that medication-naïve children and adolescents with ASD presented significantly more subjective and objective sleep alterations compared to TD and identified possible moderators of these differences. Future research requires an analysis of how these sleep alterations are linked to core symptom severity and comorbid behavioural problems, which would provide an integrated therapeutic intervention for ASD. However, our results should be interpreted in light of the potential publication bias.</p

Use of statins and the risk of dementia and mild cognitive impairment: a systematic review and meta-analysis

We conducted a systematic review and meta-analysis to investigate whether the use of statins could be associated with the risk of all-caused dementia, Alzheimer's disease (AD), vascular dementia (VaD), and mild cognitive impairment (MCI). Major electronic databases were searched until December 27th, 2017 for studies investigating use of statins and incident cognitive decline in adults. Random-effects meta-analyses calculating relative risks (RRs) were conducted to synthesize effect sizes of individual studies. Twenty-five studies met eligibility criteria. Use of statins was significantly associated with a reduced risk of all-caused dementia (k = 16 studies, adjusted RR (aRR) = 0.849, 95% CI = 0.787-0.916, p = 0.000), AD (k = 14, aRR = 0.719, 95% CI = 0.576-0.899, p = 0.004), and MCI (k = 6, aRR = 0.737, 95% CI = 0.556-0.976, p = 0.033), but no meaningful effects on incident VaD (k = 3, aRR = 1.012, 95% CI = 0.620-1.652, p = 0.961). Subgroup analysis suggested that hydrophilic statins were associated with reduced risk of all-caused dementia (aRR = 0.877; CI = 0.818-0.940; p = 0.000) and possibly lower AD risk (aRR = 0.619; CI = 0.383-1.000; p = 0.050). Lipophilic statins were associated with reduced risk of AD (aRR = 0.639; CI = 0.449-0.908; p = 0.013) but not all-caused dementia (aRR = 0.738; CI = 0.475-1.146; p = 0.176). In conclusion, our meta-analysis suggests that the use of statins may reduce the risk of all-type dementia, AD, and MCI, but not of incident VaD

The beneficial effect on cognition of noninvasive brain stimulation intervention in patients with dementia: a network meta-analysis of randomized controlled trials

Abstract Background Dementia [i.e., Alzheimer disease (AD)], the most common neurodegenerative disease, causes profound negative impacts on executive function and quality of life. Available pharmacological treatments often fail to achieve satisfactory outcomes. Noninvasive brain stimulation (NIBS) techniques, which focally modify cortical function and enhance synaptic long-term potentiation, are potentially beneficial for the cognition in patients with AD. The aim of the current network meta-analysis (NMA) was to evaluate the efficacy and safety of different NIBS interventions in patients with AD through NMA. Methods Only randomized controlled trials (RCTs) examining NIBS interventions in patients with AD had been included. All NMA procedures were performed under the frequentist model. The primary and secondary outcomes were changes in cognitive function and quality of life, respectively. Results Nineteen RCTs (639 participants) were included. The mean treatment and follow-up durations were 5.7 and 10.5 weeks, respectively. The combination of cathodal tDCS of the left dorsolateral prefrontal cortex and anodal tDCS over the right supraorbital region (c-tDCS-F3 + a-tDCS-Fp2) was associated with a significant beneficial effect on cognition compared with sham controls (standardized mean difference=2.43, 95% confidence interval=0.61–4.26, n=12 and 11). It was also associated with the greatest beneficial effect on cognition among all the investigated NIBS approaches. All the methods were well tolerated with regard to the safety profile, as reflected in the rates of adverse events or local discomfort, as well as acceptability, as indicated by dropout rate. Conclusions The present findings provide evidence of the benefits of NIBS, especially tDCS, for beneficial effect on cognition in patients with AD. However, because of few studies included, this effect was not replicated yet in the other studies. Therefore, future larger-scale and longer follow-up duration RCTs should be warranted. Trial registration PROSPERO CRD42020209516. The current study had been approved by the Institutional Review Board of the Tri-Service General Hospital, National Defense Medical Center (TSGHIRB No. B-109-29)

The beneficial effect on cognition of noninvasive brain stimulation intervention in patients with dementia: a network meta-analysis of randomized controlled trials

Abstract Background Dementia [i.e., Alzheimer disease (AD)], the most common neurodegenerative disease, causes profound negative impacts on executive function and quality of life. Available pharmacological treatments often fail to achieve satisfactory outcomes. Noninvasive brain stimulation (NIBS) techniques, which focally modify cortical function and enhance synaptic long-term potentiation, are potentially beneficial for the cognition in patients with AD. The aim of the current network meta-analysis (NMA) was to evaluate the efficacy and safety of different NIBS interventions in patients with AD through NMA. Methods Only randomized controlled trials (RCTs) examining NIBS interventions in patients with AD had been included. All NMA procedures were performed under the frequentist model. The primary and secondary outcomes were changes in cognitive function and quality of life, respectively. Results Nineteen RCTs (639 participants) were included. The mean treatment and follow-up durations were 5.7 and 10.5 weeks, respectively. The combination of cathodal tDCS of the left dorsolateral prefrontal cortex and anodal tDCS over the right supraorbital region (c-tDCS-F3 + a-tDCS-Fp2) was associated with a significant beneficial effect on cognition compared with sham controls (standardized mean difference=2.43, 95% confidence interval=0.61–4.26, n=12 and 11). It was also associated with the greatest beneficial effect on cognition among all the investigated NIBS approaches. All the methods were well tolerated with regard to the safety profile, as reflected in the rates of adverse events or local discomfort, as well as acceptability, as indicated by dropout rate. Conclusions The present findings provide evidence of the benefits of NIBS, especially tDCS, for beneficial effect on cognition in patients with AD. However, because of few studies included, this effect was not replicated yet in the other studies. Therefore, future larger-scale and longer follow-up duration RCTs should be warranted. Trial registration PROSPERO CRD42020209516. The current study had been approved by the Institutional Review Board of the Tri-Service General Hospital, National Defense Medical Center (TSGHIRB No. B-109-29)