scholarly journals Avoiding bias in trials in which allocation ratio is varied

2018 ◽  
Vol 111 (4) ◽  
pp. 143-144 ◽  
Author(s):  
Douglas G Altman
Keyword(s):  
Allocation Ratio

scholarly journals Effectiveness of using a meditation app in reducing anxiety and improving well-being during the COVID-19 pandemic: A structured summary of a study protocol for a randomized controlled trial

Trials ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
Katherine T. O’Donnell ◽  
Melanie Dunbar ◽  
Diana L. Speelman
Keyword(s):  
Randomized Controlled Trial ◽  
Controlled Trial ◽  
Well Being ◽  
Intervention Period ◽  
Post Intervention ◽  
Randomized Controlled ◽  
Survey Questions ◽  
Full Protocol ◽  
Allocation Ratio ◽  
Survey Responses

Abstract Objectives This interventional study will investigate the effect of daily use of a mindfulness app on measures of participant anxiety, well-being, and perceived outlook during the COVID-19 pandemic, by comparing pre-intervention survey responses to post-intervention survey responses. Trial design Randomized, controlled trial with parallel assignment. Adults will be assigned either to daily use of a meditation app for 30 days or to a control group (no usage of meditation app) with a 1:1 equivalence allocation ratio. Participants Inclusion Criteria: Participants must be 18 or older, have a smartphone, able to download apps to their smartphone, must be fluent in the English language, able to complete surveys on their own, and must be in the United States for the duration of the study. Exclusion Criteria: Current regular use of a mindfulness or meditation app, regular practice of mindfulness or meditation, regular therapy sessions, inability to complete surveys independently, or any mental health restrictions that would prevent participation. All data will be collected through the Insight Timer Meditation App and Google Forms. This trial is being conducted through the Lake Erie College of Osteopathic Medicine in Erie, PA, with all data collected digitally. Intervention and comparator Intervention: Participants will be sent a link to a pre-intervention survey prior to first use of the mindfulness app. Participants will be instructed to use the Insight Timer app for 10 minutes daily for 30 days. At the end of the 30-day intervention period, participants will be sent a link for the post-intervention survey. Two months after the conclusion of the 30-day intervention period, participants will be sent a link for another post-intervention survey. Comparator: Participants will receive the same surveys, but will not use any mindfulness app for the 30-day intervention period. After this 30-day period, participants are invited to use the Insight Timer app if they so choose. Main outcomes The main outcomes are (1) anxiety as assessed by survey questions adapted from the GAD7, comparing pre-intervention to post-30-days of app usage and (2) well-being as assessed by survey questions adapted from the WHO-5, comparing pre-intervention and post-30-days of app usage. Randomization Participants will be allocated to interventions via a block random sequence generator with a 1:1 allocation ratio in blocks of 8. Blinding (masking) No masking is being used in this study (open label). Numbers to be randomized (sample size) Approximately 75 participants will be randomized to each group, with an estimated enrollment of 150 participants. Trial status This study is protocol version number 27-126 and was approved on May 10, 2020. Recruitment began on August 19, 2020 and will end February 28, 2021. The study is estimated to complete on April 30, 2021. Trial registration This trial was registered to ClinicalTrials.gov on 30 April 2020. The ClinicalTrials.gov Identifier is NCT04369378. Full protocol The full protocol is attached as an additional file, accessible from the Trials website (Additional File 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol.

scholarly journals INFLUENCE OF GOVERNMENT CREDIT RISK ON PPP PROJECTS IN OPERATION STAGE

2021 ◽  
Vol 25 (3) ◽  
pp. 216-227
Author(s):  
Yining Zhou ◽  
Jicai Liu
Keyword(s):  
Credit Risk ◽  
Credit Rating ◽  
Negative Impact ◽  
Optimal Choice ◽  
Default Probability ◽  
Effort Level ◽  
Contractual Relationship ◽  
Allocation Ratio ◽  
Government Credit ◽  
The Government

In PPP projects, insufficient risk management may lead to the breakdown of partnerships and even project failures. Among them, the government credit risk is regarded as unbearable risk and a key risk affecting PPP projects because of its high frequency and impact. Therefore, based on the contractual relationship between both sides, a principal-agent model for the optimal choice of investors and the government under the government default probability is constructed. This paper explored the quantity relationship of the government credit risk and the project utility through analysing the effect of government default probability perceived by both parties on the investor’s optimal effort level and government allocation ratio. The results demonstrate that the government credit risk will decrease the effort level of investors and have a negative impact on the utility of the project. Furthermore, the government’s modification of the contract allocation ratio based on its own credit rating can offset the negative impact of its credit risk on the effectiveness of the project. But this regulatory effect is limited. The findings effectively provide some insights and theoretical basis for solving the negative effects of government credit risk.

scholarly journals Evaluation of FunFRIENDS program in prevention of anxiety in Brazilian children: a randomized controlled pilot trial

2020 ◽  
Vol 25 (11) ◽  
pp. 4497-4508
Author(s):  
Lina Maria Herrera Nunez Rivero ◽  
André Luiz Monezi Andrade ◽  
Larissa Zeggio Perez Figueredo ◽  
Bruno de Oliveira Pinheiro ◽  
Denise De Micheli
Keyword(s):  
Pilot Trial ◽  
Intervention Group ◽  
Anxiety Symptoms ◽  
Future Research ◽  
Control Group ◽  
Behavioral Profile ◽  
Intention To Treat ◽  
Randomized Controlled ◽  
Allocation Ratio ◽  
The City

Abstract This study aimed to evaluate the effects of the FunFRIENDS protocol on anxiety symptoms, internalizing problems and prosocial behavior in 4- to 5-year old children. Participated of this study 43 children with an allocation ratio of 1:1 between groups (Intervention Group [IG], N = 21; Control Group [CG], N = 22) from a public school in the city of Sao Paulo participated in the study. Behaviors were evaluated by using standardized questionnaires (PAS, CBCL, SDQ, SCBE) assessing the behavioral profile of the children at three different periods; baseline (T0), one month (T1) and three months (T2) after the intervention. It was observed a reduction in the intensity of anxiety symptoms in the IG after the intervention but with no significant effect. Overall, there were no significant differences between the IG and the CG in most behaviors on all periods evaluated. On both Intention-to-Treat analyses also it was not detected significant effects of the intervention. This is the first Brazilian study evaluating the effects of FunFRIENDS program and the implications of these findings are discussed and its significance for future research.

scholarly journals Honey and Nigella Sativa in the Prophylaxis of COVID-19; A Randomized Controlled Trial

2021 ◽  
Author(s):  
Sohaib Ashraf ◽  
Shoaib Ashraf ◽  
Rutaba Akmal ◽  
Moneeb Ashraf ◽  
Larab Kalsoom ◽  
...  
Keyword(s):  
Clinical Trial ◽  
High Risk ◽  
Sample Size ◽  
Nigella Sativa ◽  
Risk Exposure ◽  
Medical Institute ◽  
Care Providers ◽  
Post Graduate ◽  
Graduate Medical ◽  
Allocation Ratio

Abstract ObjectivesConsidering the therapeutic potential of honey and Nigella sativa (HNS) in coronavirus disease 2019 (COVID-19) patients, the objective of the study is defined to evaluate the prophylactic role of HNS. Trial designThe study is a randomized, placebo-controlled, adaptive clinical trial with parallel group design, superiority framework with an allocation ratio of 1:1 among experimental (HNS) and placebo group. An interim analysis will be done when half of the patients have been recruited to evaluate the need to adapt sample size, efficacy, and futility of the trial.ParticipantsAll asymptomatic patients with hospital or community based COVID-19 exposure will be screened if they have had 4 days exposure to a confirmed case. Non-pregnant adults with significant exposure level will be enrolled in the study● High-risk exposure (<6 feet distance for >10min without face protection) ● Moderate exposure (<6 feet distance for >10min with face protection)Subjects with acute or chronic infection, COVID-19 vaccinated, and allergy to HNS will be excluded from the study.Recruitment will be done at Shaikh Zayed Post-Graduate Medical Institute, Ali Clinic and Doctors Lounge in Lahore (Pakistan). Intervention and comparatorIn this clinical study, patients will receive either raw natural honey (0.5 g) and encapsulated organic Nigella sativa seeds (40 mg) per kg body weight per day or empty capsule with and 30 ml of 5% dextrose water as a placebo for 14 days. Both the natural products will be certified for standardization by Government College University (Botany department). Furthermore, each patient will be given standard care therapy according to version 3.0 of the COVID-19 clinical management guidelines by the Ministry of National Health Services of Pakistan.Main outcomesPrimary outcome will be Incidence of COVID-19 cases within 14 days of randomisation. Secondary endpoints include incidence of COVID-19-related symptoms, hospitalizations, and deaths along with the severity of COVID-19-related symptoms till 14th day of randomization. RandomisationParticipants will be randomized into experimental and control groups (1:1 allocation ratio) via the lottery method. There will be stratification based on high risk and moderate risk exposure. Blinding (masking)Quadruple blinding will be ensured for the participants, care providers and outcome accessors. Data analysts will also be blinded to avoid conflict of interest. Site principal investigator will be responsible for ensuring masking.Numbers to be randomised (sample size)1000 participants will be enrolled in the study with 1:1 allocation.Trial StatusThe final protocol version 1.4 was approved by institutional review board of Shaikh Zayed Post-Graduate Medical Complex on February 15, 2021. The trial recruitment was started on March 05, 2021, with a trial completion date of February 15, 2022. Trial registrationClinical trial was registered on February 23, 2021, www.clinicaltrials.gov with registration ID NCT04767087.

scholarly journals The efficacy of Siddha Medicine, Kabasura Kudineer (KSK) compared to Vitamin C & Zinc (CZ) supplementation in the management of asymptomatic COVID-19 cases: A structured summary of a study protocol for a randomised controlled trial

Trials ◽  
2020 ◽  
Vol 21 (1) ◽  
Author(s):  
S. Natarajan ◽  
C. Anbarasi ◽  
P. Sathiyarajeswaran ◽  
P. Manickam ◽  
S. Geetha ◽  
...  
Keyword(s):  
Data Analysis ◽  
Vitamin C ◽  
Sample Size ◽  
Study Protocol ◽  
Controlled Trial ◽  
Severe Illness ◽  
Control Group ◽  
Rt Pcr ◽  
Full Protocol ◽  
Allocation Ratio

Abstract Objectives The primary objectives of this study are to determine efficacy of Siddha medicine, Kabasura kudineer in reduction of SARS-CoV-2 viral load and reducing the onset of symptoms in asymptomatic COVID-19 when compared to Vitamin C and Zinc (CZ) supplementation. In addition, the trial will examine the changes in the immunological markers of the Siddha medicine against control. The secondary objectives of the trial are to evaluate the safety of the Siddha medicine and to document clinical profile of asymptomatic COVID-19 as per principles of Siddha system of Medicine. Trial design A single centre, open-label, parallel group (1:1 allocation ratio), exploratory randomized controlled trial. Participants Cases admitted at non-hospital settings designated as COVID Care Centre and managed by the State Government Stanley Medical College, Chennai, Tamil Nadu, India will be recruited. Eligible participants will be those tested positive for COVID-19 by Reverse Transcriptase Polymerase Chain reaction (RT-PCR) aged 18 to 55 years without any symptoms and co-morbidities like diabetes mellitus, hypertension and bronchial asthma. Those pregnant or lactating, with severe respiratory disease, already participating in COVID trials and with severe illness like malignancy will be excluded. Intervention and comparator Adopting traditional methods, decoction of Kabasura kudineer will be prepared by boiling 5g of KSK powder in 240 ml water and reduced to one-fourth (60ml) and filtered. The KSK group will receive a dose of 60ml decoction, orally in the morning and evening after food for 14 days. The control group will receive Vitamin C (60000 IU) and Zinc tablets (100mg) orally in the morning and evening respectively for 14 days. Main outcomes The primary outcomes are the reduction in the SARS-CoV-2 load [as measured by cyclic threshold (CT) value of RT-PCR] from the baseline to that of seventh day of the treatment, prevention of progression of asymptomatic to symptomatic state (clinical symptoms like fever, cough and breathlessness) and changes in the immunity markers [Interleukins (IL) 6, IL10, IL2, Interferon gamma (IFNγ) and Tumor Necrosis Factor (TNF) alpha]. Clinical assessment of COVID-19 as per standard Siddha system of medicine principles and the occurrence of adverse effects will be documented as secondary outcomes. Randomisation The assignment to the study or control group will be allocated in equal numbers through randomization using random number generation in Microsoft Excel by a statistician who is not involved in the trial. The allocation scheme will be made by an independent statistician using a sealed envelope. The participants will be allocated immediately after the eligibility assessment and informed consent procedures. Blinding (masking) This study is unblinded. The investigators will be blinded to data analysis, which will be carried out by a statistician who is not involved in the trial. Numbers to be randomised (sample size) Sample size could not be calculated, as there is no prior trial on KSK. This trial will be a pilot trial. Hence, we intend to recruit 60 participants in total using a 1:1 allocation ratio, with 30 participants randomised into each arm. Trial status Protocol version 2.0 dated 16th May 2020. Recruitment is completed. The trial started recruitment on the 25th May 2020. We anticipate study including data analysis will finish on November 2020. We also stated that protocol was submitted before the end of data collection Trial registration The study protocol was registered with clinical trial registry of India (CTRI) with CTRI/2020/05/025215 on 16 May 2020. Full protocol The full protocol is attached as an additional file, accessible from the Trials website (Additional file 1). In the interest in expediting dissemination of this material, the familiar formatting has been eliminated; this Letter serves as a summary of the key elements of the full protocol. The study protocol has been reported in accordance with the Standard Protocol Items: Recommendations for Clinical Interventional Trials (SPIRIT) guidelines (Additional file 2).

Homogenization of Japanese Industrial Technology From the Perspective of R&D Expenses

2021 ◽  
Vol 11 (2) ◽  
pp. 24-51
Author(s):  
Hirokazu Yamada
Keyword(s):  
New Products ◽  
Japanese Economy ◽  
Industrial Technology ◽  
Technical Knowledge ◽  
Structure Changes ◽  
Technological Structure ◽  
Information And Communication ◽  
Japanese Industry ◽  
Allocation Ratio ◽  
Electronic Parts

The aim of this paper is to discuss the reasons for the decline in the profitability of Japanese R&D from the perspective of in-house R&D efforts. Focusing on changes in the allocation ratio of in-house R&D expenses by industry from 1972 to 2017, technological structure changes in the Japanese industry during that period are empirically analyzed. Based on the analysis, the technological structure of the Japanese industry has been consistently moving toward homogenization since 1972. Homogenization is mainly directed toward the related technical fields of automobiles and information and communication machinery/equipment/electronic parts, which are the main industries that currently lead the Japanese economy. While the types of technical knowledge possessed by the Japanese industry are decreasing, there is a lack of R&D activities that will create new products and markets and increase the pie of the Japanese industry or greatly promote the metabolism of technology of the entire industry.

Generalized Efron's biased coin design and its theoretical properties

2016 ◽  
Vol 53 (2) ◽  
pp. 327-340 ◽  
Author(s):  
Yanqing Hu
Keyword(s):  
Clinical Trials ◽  
General Theory ◽  
Convergence Rate ◽  
Biased Coin Design ◽  
Target Ratio ◽  
Allocation Ratio ◽  
Target Allocation ◽  
Biased Coin

Abstract In clinical trials with two treatment arms, Efron's biased coin design, Efron (1971), sequentially assigns a patient to the underrepresented arm with probability p > ½. Under this design the proportion of patients in any arm converges to ½, and the convergence rate is n-1, as opposed to n-½ under some other popular designs. The generalization of Efron's design to K ≥ 2 arms and an unequal target allocation ratio (q1, . . ., qK) can be found in some papers, most of which determine the allocation probabilities ps in a heuristic way. Nonetheless, it has been noted that by using inappropriate ps, the proportion of patients in the K arms never converges to the target ratio. We develop a general theory to answer the question of what allocation probabilities ensure that the realized proportions under a generalized design still converge to the target ratio (q1, . . ., qK) with rate n-1.

Sign in / Sign up

Export Citation Format

Share Document