What improvements do Cochrane systematic reviewers suggest for the design of trials?

Background: Many randomised trials have serious methodological flaws that fatally undermine their results, which makes the research wasteful. This is of concern for many, including those doing systematic reviews that include trials. Cochrane systematic reviews all have a section called ‘Implications for research’, which allows authors of the review to present their conclusions on how future research might be improved. Looking at these conclusions might highlight priority areas for improvement. Methods: We focused on the Cochrane Schizophrenia Review Group and the Multiple sclerosis and rare diseases of the central nervous system Review Group (the MS Review Group). Reviews with citations between 2009 and 2019 were identified and the recommendations given by review authors in ‘Implications for research’ were put into categories. Results: Between 2009 and 2019 we identified 162 reviews for the Schizophrenia Review Group and 43 reviews for the MS Review Group. We created 22 categories in total, of which 12 were common to both groups. The five most used categories were the same for both: better choice of outcomes; better choice of intervention/comparator; longer follow-up; larger sample size; use of validated scales. Better choice of outcomes and/or intervention/comparator was recommended in over 50% of reviews. Longer follow-up and larger sample size were recommended in over a third, with use of validated scales being suggested in around a fifth of reviews. There was no obvious pattern of improvement over time for trials included in systematic reviews published by both groups. Conclusions: We suggest that trialists working in these areas (and others too) ask themselves why they have chosen their particular outcomes, intervention and comparator, whether follow-up is long enough, if the sample size is big enough and whether the scales they choose to measure their outcomes are appropriate.

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Learning from Cochrane systematic reviews: what improvements do these suggest for the design of trials?

F1000Research ◽

10.12688/f1000research.22635.2 ◽

2020 ◽

Vol 9 ◽

pp. 178

Author(s):

Stefania Pirosca ◽

Mike Clarke ◽

Shaun Treweek

Keyword(s):

Sample Size ◽

Systematic Reviews ◽

Future Research ◽

Randomised Trials ◽

Review Group ◽

The Central Nervous System ◽

System Review ◽

Larger Sample ◽

Do So

Background: Many randomised trials have serious methodological flaws that fatally undermine their results, which makes the research wasteful. This is of concern for many, including those doing systematic reviews that include trials. Cochrane systematic reviews have a section called ‘ Implications for research’, which allows authors of the review to present their conclusions on how future research might be improved. Looking at these conclusions might highlight priority areas for improvement. Methods: We focused on the Cochrane Schizophrenia Review Group and the Multiple sclerosis and rare diseases of the central nervous system Review Group (the MS Review Group). Reviews with citation dates between 2009 and 2019 were identified and the recommendations of review authors in ‘ Implications for research’ were put into categories. Results: Between 2009 and 2019 we identified 162 reviews for the Schizophrenia Review Group and 43 reviews for the MS Review Group. We created 22 categories of recommendations in total, of which 12 were common to both groups. The five most used categories were the same for both: better choice of outcomes; better choice of intervention/comparator; longer follow-up; larger sample size; use of validated scales. Better choice of outcomes and/or intervention/comparator was recommended in over 50% of reviews. Longer follow-up and larger sample size were recommended in over a third, with use of validated scales being suggested in around a fifth of reviews. There was no obvious pattern of improvement over time for trials included in systematic reviews published by both groups. Conclusions: We suggest that trialists working in these and other areas ask themselves, or are compelled to do so by others (e.g. funders), why they have chosen their outcomes, intervention and comparator, whether follow-up is long enough, if the sample size is big enough and whether the scales they choose to measure their outcomes are appropriate.

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Methods of conduct and reporting of living systematic reviews: a protocol for a living methodological survey

F1000Research ◽

10.12688/f1000research.18005.2 ◽

2019 ◽

Vol 8 ◽

pp. 221 ◽

Cited By ~ 3

Author(s):

Assem M. Khamis ◽

Lara A. Kahale ◽

Hector Pardo-Hernandez ◽

Holger J. Schünemann ◽

Elie A. Akl

Keyword(s):

Systematic Review ◽

Systematic Reviews ◽

Evidence Synthesis ◽

Cochrane Library ◽

Cross Sectional Survey ◽

Systematic Review Methodology ◽

Cross Sectional ◽

Prospective Longitudinal ◽

Over Time

Background: The living systematic review (LSR) is an emerging approach for improved evidence synthesis that uses continual updating to include relevant new evidence as soon as it is published. The objectives of this study are to: 1) assess the methods of conduct and reporting of living systematic reviews using a living study approach; and 2) describe the life cycle of living systematic reviews, i.e., describe the changes over time to their methods and findings. Methods: For objective 1, we will begin by conducting a cross-sectional survey and then update its findings every 6 months by including newly published LSRs. For objective 2, we will conduct a prospective longitudinal follow-up of the cohort of included LSRs. To identify LSRs, we will continually search the following electronic databases: Medline, EMBASE and the Cochrane library. We will also contact groups conducting LSRs to identify eligible studies that we might have missed. We will follow the standard systematic review methodology for study selection and data abstraction. For each LSR update, we will abstract information on the following: 1) general characteristics, 2) systematic review methodology, 3) living approach methodology, 4) results, and 5) editorial and publication processes. We will update the findings of both the surveys and the longitudinal follow-up of included LSRs every 6 months. In addition, we will identify articles addressing LSR methods to be included in an ‘LSR methods repository’. Conclusion: The proposed living methodological survey will allow us to monitor how the methods of conduct, and reporting as well as the findings of LSRs change over time. Ultimately this should help with ensuring the quality and transparency of LSRs.

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Sounds Affecting the Moments of Stuttering in Multilingualism: A Case Study

Communication Disorders Quarterly ◽

10.1177/1525740116658008 ◽

2016 ◽

Vol 38 (3) ◽

pp. 154-160 ◽

Cited By ~ 1

Author(s):

Taryn Morrish ◽

Amy Nesbitt ◽

Mia le Roux ◽

Ursula Zsilavecz ◽

Jeannie van der Linde

Keyword(s):

Sample Size ◽

Language Proficiency ◽

Mixed Method ◽

Interrater Reliability ◽

Future Research ◽

African Language ◽

Mixed Method Design ◽

Larger Sample

Research involving stuttering in multilingual individuals is limited. Speech-language therapists face the challenge of treating a diverse client base, which includes multilingual individuals. The aim of this study was to examine the stuttering moments across English, Afrikaans, and German in a multilingual speaker. A single multilingual adult with a severe developmental stutter participated in this study. A mixed-method design was implemented. The results were perceptually analyzed, and interrater reliability was determined. The results revealed that the voiceless plosive [k], the voiceless fricative [f], and the plosive-lateral approximant cluster [kl] caused stuttering moments across the languages. More stuttering moments occurred on consonants as opposed to vowels. The most prominent core behavior was prolongations. Language proficiency plays a role in the increase of the moments of stuttering in the least proficient language. Future research on a larger sample size is recommended. Research on African language speaking multilingual person who stutters (PWS) should be pursued.

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Short Implants in Maxillary and Mandibular Rehabilitations: Interim Results (6 to 42 Months) of a Prospective Study

Journal of Oral Implantology ◽

10.1563/aaid-joi-d-12-00206 ◽

2015 ◽

Vol 41 (1) ◽

pp. 50-55 ◽

Cited By ~ 4

Author(s):

Silvio Taschieri ◽

Stefano Corbella ◽

Raffaella Molinari ◽

Massimo Saita ◽

Massimo Del Fabbro

Keyword(s):

Sample Size ◽

Cumulative Survival ◽

Short Implants ◽

Significant Difference ◽

Upper Jaw ◽

Maxilla And Mandible ◽

A Prospective Study ◽

Bone Height ◽

Larger Sample

The aim of this single-cohort study was to evaluate clinical survival and success of partial rehabilitation supported by reduced-length implants in maxilla and mandible. Data from 53 short implants placed in 41 patients are presented. Before surgery mean residual bone height was 6.21 ± 1.05 mm in the upper jaw and 10.73 ± 1.63 mm in the mandible. None of the implants failed, and the cumulative survival rate was 100% at 1 year after prosthetic loading. Mean peri-implant bone loss was 0.69 ± 0.24 mm for maxillary implants and 0.73 ± 0.23 mm for mandibular implants, and there was no significant difference between the 2 jaws. No complications were recorded. Despite the limitations of this study concerning study design and sample size, short implants may be considered effective in supporting partial rehabilitation in both maxilla and mandible. More well-designed studies with a larger sample size and longer follow-up are needed to validate the use of short implants.

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COVID-19: underpowered randomised trials, or no randomised trials?

Trials ◽

10.1186/s13063-021-05209-5 ◽

2021 ◽

Vol 22 (1) ◽

Author(s):

Atle Fretheim

Keyword(s):

Public Health ◽

Sample Size ◽

Systematic Reviews ◽

Sample Size Calculation ◽

Scientific Progress ◽

Face Mask ◽

Health Interventions ◽

Randomised Trials ◽

Public Health Interventions ◽

Key Barrier

AbstractA recently published trial of face mask use to protect against COVID-19 demonstrated a key barrier to carrying out randomised trials in public health: the need for unattainably large sample sizes. For many public health interventions, the choice is not between sufficiently powered trials and underpowered trials, but between underpowered trials and no trials at all. Underpowered trials should be viewed as contributions to the larger body of evidence, alongside other studies of various sizes and designs, collectively assessed and synthesized in systematic reviews. Overemphasis on sample size calculation is probably more of a hindrance than a help to scientific progress.

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Theory of Planned Behavior Analysis of Social Distancing During the COVID-19 Pandemic: Focusing on the Intention–Behavior Gap

Annals of Behavioral Medicine ◽

10.1093/abm/kaab041 ◽

2021 ◽

Author(s):

Laurel P Gibson ◽

Renee E Magnan ◽

Emily B Kramer ◽

Angela D Bryan

Keyword(s):

Theory Of Planned Behavior ◽

Planned Behavior ◽

Behavioral Control ◽

Longitudinal Design ◽

Subjective Norms ◽

Future Research ◽

Perceived Behavioral Control ◽

Social Distancing ◽

Over Time

Abstract Background As COVID-19 continues to spread globally, it is important to understand psychological factors that may influence compliance with social distancing. Purpose The present study examined whether Theory of Planned Behavior (TPB) constructs were associated with social distancing, with a focus on exploring moderators of the intention–behavior relationship. Methods Using a longitudinal design, U.S. adults (N = 507) self-reported TPB constructs and social distancing behavior at baseline and 3 months later. Participants were from 48 U.S. States and the District of Columbia and were on average 50.39 years old (SD = 15.32, range = 18–80). The majority were Non-Hispanic White (71.6%), had a bachelor’s degree or higher (55.3%), and resided in suburban areas (55.8%). Results While positive attitudes toward social distancing increased over time (p = .002), subjective norms weakened (p < .001) and perceived behavioral control (PBC) remained stable (p = .22). Interestingly, despite an increase in intentions from baseline to follow-up (p < .001), there was a significant decrease in social distancing behavior over time (p < .001). Consistent with the TPB, baseline attitudes (p < .001), subjective norms (p < .001), and PBC (p < .001) for social distancing were all associated with baseline intentions to social distance. In turn, baseline intentions were significantly associated with social distancing behavior at follow-up (p < .001). Younger adults (p < .001) and non-White participants (p = .002) displayed a greater intention–behavior gap relative to older and White participants. In contrast, participants with more stable intentions over time displayed a stronger intention–behavior relationship (p < .001). Conclusions Targeting individuals’ attitudes, norms, and PBC may effectively promote protective behaviors intended to mitigate the spread of COVID-19 and similar viral outbreaks. Future research should examine effective strategies for translating social distancing intentions into actions.

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Methods of conduct and reporting of living systematic reviews: a protocol for a living methodological survey

F1000Research ◽

10.12688/f1000research.18005.1 ◽

2019 ◽

Vol 8 ◽

pp. 221

Author(s):

Assem M. Khamis ◽

Lara A. Kahale ◽

Hector Pardo-Hernandez ◽

Holger J. Schünemann ◽

Elie A. Akl

Keyword(s):

Systematic Review ◽

Systematic Reviews ◽

Evidence Synthesis ◽

Cochrane Library ◽

Cross Sectional Survey ◽

Systematic Review Methodology ◽

Cross Sectional ◽

Prospective Longitudinal ◽

Over Time

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A CONTINUED STUDY TO DERTERMINE THE ASSOCIATION BETWEEN CHRONIC KIDNEY DISEASE AND NON-ALCOHALIC FATTY LIVER DISEASE AND ITS EFFECT ON eGFR

10.36106/gjra/1011593 ◽

2021 ◽

pp. 133-136

Author(s):

Arvind Gupta ◽

Poonam Gupta ◽

Anubha Srivastava ◽

Amit Kumar Panday

Keyword(s):

Chronic Kidney Disease ◽

Kidney Disease ◽

Physical Examination ◽

Sample Size ◽

Care Center ◽

Tertiary Care ◽

Ckd Stage ◽

High Prevalence ◽

Larger Sample

Background: The present study was conduct in Motilal Nehru Medical College, Swaroop Rani Nehru Hospital Prayagraj, a tertiary care center and data was collected over a period from January 2019 to April 2020. All 78 patients of CKD attending OPD & IPD of General Medicine and Nephrology, diagnosed by suggestive symptoms and conrmed by physical examination and laboratory investigations were taken , Among the subjects, those having NAFLD were grouped as cases. Patients of Chronic Kidney disease not having NAFLD were grouped as controls. Aim & Objective: To study the prevalence of NAFLD in patients of CKD and establish the association between NAFLD and CKD by studying the effect of NAFLD on eGFR. Methodology: This was a 16 month case control study. Total 78 patients with age 18-65 years , Either sex with Chronic kidney disease diagnosed by USG, KFT, physical examination and having NAFLD Patients with known diagnosis of metabolic syndrome, diabetes and/or hypothyroidism. Those on hepatotoxic medication (amiodarone, barbiturates, glucocorticoids, etc.). The data so collected was entered into computer using Microsoft Excel 2013 software and was subjected to statistical analysis. Result : The ndings of present study thus reafrm the observations of previous studies that highlight a high prevalence of NAFLD in CKD patients and link it to the deranged metabolic factors. In present study we could not found a convincing evidence supporting a relationship between NAFLD and its severity with progression of CKD, probably owing to three major factors – rst, owing to Discussion 71 limitation of study population in only CKD stage 3 and secondly, owing to absence of retrospective data tracing the time of development of NAFLD in these patients and thirdly, inability to carry out long-time follow-up of patients. In present study, though minor changes in eGFR values in patients were seen, however, during the limited period of follow-up no shift from Stage 3 to other stages of CKD was observed. All the patients were regular in follow-up and had a good medical compliance and in general did not show a phenomenal deterioration in renal function within the short span of study. Keeping in view these limitations, further studies are recommended on a larger sample size with inclusion of patients from different stages of CKD spanning over a longer duration of follow-up to see whether NAFLD presence and its severity has a relationship with long-term progression of CKD. Conclusion: The present study showed that, CKD patients had a high prevalence of NAFLD. The ndings also show that FIB-4 scores are useful noninvasive methods for detection of NAFLD in CKD patients. The ndings showed a possible signicant association between NAFLD and lower eGFR rates. One of the limitations of the present study was presence of only Stage 3 CKD patients, owing to which the linear correlations between eGFR and NAFLD severity could not be assessed properly. Further studies on larger sample size with inclusion of patients with other CKD stages too are recommended.

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Replication and contradiction of highly cited research papers in psychiatry: 10-year follow-up

The British Journal of Psychiatry ◽

10.1192/bjp.bp.113.143701 ◽

2015 ◽

Vol 207 (4) ◽

pp. 357-362 ◽

Cited By ~ 30

Author(s):

Aran Tajika ◽

Yusuke Ogawa ◽

Nozomi Takeshima ◽

Yu Hayasaka ◽

Toshi A. Furukawa

Keyword(s):

Sample Size ◽

Small Sample Size ◽

Total Sample ◽

Small Sample ◽

Research Papers ◽

Effective Interventions ◽

Mean Differences ◽

Larger Sample ◽

Highly Cited

BackgroundContradictions and initial overestimates are not unusual among highly cited studies. However, this issue has not been researched in psychiatry.AimsTo assess how highly cited studies in psychiatry are replicated by subsequent studies.MethodWe selected highly cited studies claiming effective psychiatric treatments in the years 2000 through 2002. For each of these studies we searched for subsequent studies with a better-controlled design, or with a similar design but a larger sample.ResultsAmong 83 articles recommending effective interventions, 40 had not been subject to any attempt at replication, 16 were contradicted, 11 were found to have substantially smaller effects and only 16 were replicated. The standardised mean differences of the initial studies were overestimated by 132%. Studies with a total sample size of 100 or more tended to produce replicable results.ConclusionsCaution is needed when a study with a small sample size reports a large effect.

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An Open Trial of a Mind–Body Intervention for Young Women with Moderate to Severe Primary Dysmenorrhea

Pain Medicine ◽

10.1093/pm/pnz378 ◽

2020 ◽

Vol 21 (7) ◽

pp. 1385-1392

Author(s):

Laura A Payne ◽

Laura C Seidman ◽

Tamineh Romero ◽

Myung-Shin Sim

Keyword(s):

Pain Catastrophizing ◽

Medication Use ◽

Open Trial ◽

Self Report ◽

Future Research ◽

Adult Women ◽

Primary Dysmenorrhea ◽

Menstrual Pain ◽

Over Time

Abstract Objective To evaluate the feasibility, acceptability, and preliminary efficacy of a mind–body intervention for moderate to severe primary dysmenorrhea (PD). Design Open trial (single arm). Setting Academic medical school. Subjects A total of 20 young adult women with moderate to severe primary dysmenorrhea were included across four separate intervention groups. Methods All participants received five 90-minute sessions of a mind–body intervention and completed self-report measures of menstrual pain, depression, anxiety, somatization, and pain catastrophizing at baseline, post-treatment, and at one-, two-, three-, and 12-month follow-up. Self-report of medication use and use of skills learned during the intervention were also collected at all follow-up points. Results Participants reported significantly lower menstrual pain over time compared with baseline. No changes in anxiety, depression, or somatization were observed, although pain catastrophizing improved over time. Changes in menstrual pain were not associated with changes in medication use or reported use of skills. Conclusions A mind–body intervention is a promising nondrug intervention for primary dysmenorrhea, and future research should focus on testing the intervention further as part of a randomized clinical trial.

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