"Innovative Sample Size Methods for Clinical Trials" is hosted to coincide with the Spring 2018 update to nQuery - The leading Sample Size Software.
Hosted by Ronan Fitzpatrick - Head of Statistics and nQuery Lead Researcher at Statsols - you'll learn about the benefits of a range of procedures and how you can implement them into your work:
1) Dose-escalation with the Bayesian Continual Reassessment Method
CRM is a growing alternative to the 3+3 method for Phase I trials finding the Maximum Tolerated Dose (MTD).
See how researchers can overcome 3+3 drawbacks to easily find the required sample size for this beneficial alternative for finding the MTD.
2) Bayesian Assurance with Survival Example
This Bayesian alternative to power has experienced a rapid rise in interest and application from researchers.
See how Assurance is being used by researchers to discover the true “probability of success” of a trial.
3) Mendelian Randomization
Mendelian randomization (MR) is a method that allows testing of a causal effect from observational data in the presence of confounding factors.
However, in order to design efficient Mendelian randomization studies, it is essential to calculate the appropriate sample sizes required. We demonstrate what to do to achieve this.
4) Negative Binomial Distribution
Negative binomial model has been increasingly used to model the count data. One of the challenges of applying negative binomial model in clinical trial design is the sample size estimation.
We demonstrate how best to determine the appropriate sample size in the presence of challenges such as unequal follow-up or dispersion.
Webinar slides- alternatives to the p-value and power nQuery
What are the alternatives to the p-value & power? What is the next step for sample size determination? We will explore these issues in this free webinar presented by nQuery
2020 trends in biostatistics what you should know about study design - slid...nQuery
2020 Trends In Biostatistics - What you should know about study design.
In this free webinar you will learn about:
-Adaptive designs in confirmatory trials
-Using external data in study planning
-Innovative designs in early-stage trials
To watch the full webinar:
https://www.statsols.com/webinar/2020-trends-in-biostatistics-what-you-should-know-about-study-design
Sample size for survival analysis - a guide to planning successful clinical t...nQuery
Determining the appropriate number of events needed for survival analysis is a complex task as study planners try to predict what sample size will be needed after accounting for the complications of unequal follow-up, drop-out and treatment crossover.
The statistical, logistical and ethical considerations all complicate life for biostatisticians as issues to balance in planning a survival analysis. However, this complexity has created a need for new analyses and procedures to help the planning process for survival analysis trials.
The wider move from fixed to flexible designs has opened up opportunities for advanced methods such as adaptive design and Bayesian analysis to help deal with the unique complications of planning for survival data but these methods have their own complications that need to be explored too.
Designing studies with recurrent events | Model choices, pitfalls and group s...nQuery
In this free webinar, we will examine the important design considerations for analyzing recurring events and counts.
Watch the webinar at: https://www.statsols.com/en/webinar/designing-studies-with-recurrent-events
Designing studies with recurrent events (Model choices, pitfalls and group sequential design)
Webinar slides how to reduce sample size ethically and responsiblynQuery
[Webinar] How to reduce sample size...ethically and responsibly | In this free webinar, you will learn various design strategies to help reduce the sample size of your study in an ethical and responsible manner. Practical examples will be used throughout.
Webinar slides sample size for survival analysis - a guide to planning succ...nQuery
Determining the appropriate number of events needed for survival analysis is a complex task as study planners try to predict what sample size will be needed after accounting for the complications of unequal follow-up, drop-out and treatment crossover.
The statistical, logistical and ethical considerations all complicate life for biostatisticians as issues to balance in planning a survival analysis. However, this complexity has created a need for new analyses and procedures to help the planning process for survival analysis trials.
The wider move from fixed to flexible designs has opened up opportunities for advanced methods such as adaptive design and Bayesian analysis to help deal with the unique complications of planning for survival data but these methods have their own complications that need to be explored too.
Non-inferiority and Equivalence Study design considerations and sample sizenQuery
About the webinar
This webinar examines the role of non-inferiority and equivalence in study design
In this free webinar, you will learn about:
-Regulatory information on this type of study design
-Considerations for study design and your sample size
-Practical worked examples of
--Non-inferiority Testing
--Equivalence Testing
Duration - 60 minutes
Speaker: Ronan Fitzpatrick, Head of Statistics, Statsols
Watch the video at: https://www.statsols.com/webinars
Webinar slides- alternatives to the p-value and power nQuery
What are the alternatives to the p-value & power? What is the next step for sample size determination? We will explore these issues in this free webinar presented by nQuery
2020 trends in biostatistics what you should know about study design - slid...nQuery
2020 Trends In Biostatistics - What you should know about study design.
In this free webinar you will learn about:
-Adaptive designs in confirmatory trials
-Using external data in study planning
-Innovative designs in early-stage trials
To watch the full webinar:
https://www.statsols.com/webinar/2020-trends-in-biostatistics-what-you-should-know-about-study-design
Sample size for survival analysis - a guide to planning successful clinical t...nQuery
Determining the appropriate number of events needed for survival analysis is a complex task as study planners try to predict what sample size will be needed after accounting for the complications of unequal follow-up, drop-out and treatment crossover.
The statistical, logistical and ethical considerations all complicate life for biostatisticians as issues to balance in planning a survival analysis. However, this complexity has created a need for new analyses and procedures to help the planning process for survival analysis trials.
The wider move from fixed to flexible designs has opened up opportunities for advanced methods such as adaptive design and Bayesian analysis to help deal with the unique complications of planning for survival data but these methods have their own complications that need to be explored too.
Designing studies with recurrent events | Model choices, pitfalls and group s...nQuery
In this free webinar, we will examine the important design considerations for analyzing recurring events and counts.
Watch the webinar at: https://www.statsols.com/en/webinar/designing-studies-with-recurrent-events
Designing studies with recurrent events (Model choices, pitfalls and group sequential design)
Webinar slides how to reduce sample size ethically and responsiblynQuery
[Webinar] How to reduce sample size...ethically and responsibly | In this free webinar, you will learn various design strategies to help reduce the sample size of your study in an ethical and responsible manner. Practical examples will be used throughout.
Webinar slides sample size for survival analysis - a guide to planning succ...nQuery
Determining the appropriate number of events needed for survival analysis is a complex task as study planners try to predict what sample size will be needed after accounting for the complications of unequal follow-up, drop-out and treatment crossover.
The statistical, logistical and ethical considerations all complicate life for biostatisticians as issues to balance in planning a survival analysis. However, this complexity has created a need for new analyses and procedures to help the planning process for survival analysis trials.
The wider move from fixed to flexible designs has opened up opportunities for advanced methods such as adaptive design and Bayesian analysis to help deal with the unique complications of planning for survival data but these methods have their own complications that need to be explored too.
Non-inferiority and Equivalence Study design considerations and sample sizenQuery
About the webinar
This webinar examines the role of non-inferiority and equivalence in study design
In this free webinar, you will learn about:
-Regulatory information on this type of study design
-Considerations for study design and your sample size
-Practical worked examples of
--Non-inferiority Testing
--Equivalence Testing
Duration - 60 minutes
Speaker: Ronan Fitzpatrick, Head of Statistics, Statsols
Watch the video at: https://www.statsols.com/webinars
Innovative sample size methods for adaptive clinical trials webinar web ver...nQuery
View the video here:
https://www.statsols.com/webinar/innovative-sample-size-methods-for-adaptive-clinical-trials
Given the high failure rates and the increased costs of clinical trials, researchers need innovative design strategies to best optimize financial resources and reduce the risk to patients.
Adaptive designs are emerging as a way to reduce risk and cost associated with clinical trials. The FDA recently published guidance (Innovative Cures Act) and are actively encouraging sponsors to use Adaptive trials.
Adaptive design is a clinical trial design that allows adaptations or modifications to aspects of the trial after its initiation without undermining the validity and integrity of the trial.
In this webinar, Ronan will demonstrate nQuery's new Adaptive module focusing on Sample Size Re-Estimation & Group-Sequential Design.
In this webinar you will learn about:
The pros and cons of adaptive designs
Sample Size Re-Estimation
Group-Sequential Design
Conditional Power
Predictive Power
Optimizing Oncology Trial Design FAQs & Common IssuesnQuery
Optimizing Oncology Trial Design - FAQs & Common Issues
In this free webinar you will learn about
Endpoints
Models
Covariates, stratification and censoring issues
Adaptive design - complications and opportunities
Sample size determination
& more
In this free webinar we will offer guidance on how to optimize your oncology trial design. Specifically, we will examine the frequently asked questions and common issues that arise.
https://www.statsols.com/webinar/optimizing-oncology-trial-design
Innovative Strategies For Successful Trial Design - Webinar SlidesnQuery
Full webinar available here: https://www.statsols.com/webinar/innovative-strategies-for-successful-trial-design
[Webinar] Innovative Strategies For Successful Trial Design- In this free webinar, you will learn about:
- The challenges facing your trials
- How to calculate the correct sample size
- Worked examples including Mixed/Hierarchical Models
- Posterior Error
- Adaptive Designs For Survival
www.statsols.com
Extending A Trial’s Design Case Studies Of Dealing With Study Design IssuesnQuery
About the webinar
As trials increase in complexity and scope, there is a requirement for trial designs to reflect this.
From dealing with non-proportional hazards in survival analysis to dealing with cluster randomization, we examine how to deal with study design issues of complex trials.
In this free webinar, you will learn about:
Dealing with study design issues
Practical worked examples of
Non-proportional Hazards
Cluster Randomization
Three Armed Trials
Non-proportional Hazards
Non-proportional hazards and complex survival curves have become of increasing interest, due to being commonly seen in immunotherapy development. This has led to interest in assessing the robustness of standard methods and alternative methods that better adapt to deviations.
In this webinar, we look at methods proposed for complex survival curves and the weighted log-rank test as a candidate model to deal with a delayed survival effect.
Cluster Randomization
Cluster-randomized designs are often adopted when there is a high risk of contamination if cluster members were randomized individually. Stepped-wedge designs are useful in cases where it is difficult to apply a particular treatment to half of the clusters at the same time.
In this webinar, we introduce cluster randomization and stepped-wedge designs to provide an insight into the requirements of more complex randomization schedules.
Three Armed Trials
Non-inferiority testing is a common hypothesis test in the development of generic medicine and medical devices. The most common design compares the proposed non-inferior treatment to the standard treatment alone but this leaves uncertain if the treatment effect is the same as from previous studies. This “assay sensitivity” problem can be resolved by using a three arm trial which includes placebo alongside the new and reference treatments for direct comparison.
In this webinar we show a complete testing approach to this gold standard design and how to find the appropriate allocation and sample size for this study.
Duration - 60 minutes
Speaker: Ronan Fitzpatrick, Head of Statistics, Statsols
Cluster randomised trials with excessive cluster sizes: ethical and design im...Karla hemming
Investigators submitting funding applications strive for nominal levels of power to ensure their applications are competitive. If the number of clusters is limited this might mean large clusters are needed to achieve that power; but a slightly lower power might be achievable with a drastic reduction in cluster sizes. Alternatively, increasing the number of clusters minimally might mean the desired level of power is achievable, again with a drastic reduction in cluster sizes.
5 essential steps for sample size determination in clinical trials slidesharenQuery
In this free webinar hosted by nQuery Researcher & Statistician Eimear Keyes, we map out the 5 essential steps for sample size determination in clinical trials. At each step, Eimear will highlight the important function it plays and how to avoid the errors that will negatively impact your sample size determination and therefore your study.
Watch the Video: https://www.statsols.com/webinar/the-5-essential-steps-for-sample-size-determination
Sample size and how to calculate it
- Why sample size is important
- Alpha and beta errors
- Main outcome and Effect size
- Practical examples using Means-Proportions-Correlation- Confidence Interval
Poster Randomization Approach in Case-Based Reasoning: Case of Study of Mammo...Miled Basma Bentaiba
This document was presented on 8 May 2018 at the doctoral symposium at IFIP International Conference on Computational Intelligence and Its Applications (IFIP CIIA 2018).
An introduction to the stepped wedge cluster randomised trial, by Dr Karla Hemming for the CLAHRC West Midlands Scientific Advisory Group meeting, 9th June 2015, Birmingham, UK
Summary of current research on routine outcome measurement, feedback, the validity, reliability, and effectiveness of the ORS and SRS (or PCOMS Outcome Management System)
Talk given at ISCB 2016 Birmingham
For indications and treatments where their use is possible, n-of-1 trials represent a promising means of investigating potential treatments for rare diseases. Each patient permits repeated comparison of the treatments being investigated and this both increases the number of observations and reduces their variability compared to conventional parallel group trials.
However, depending on whether the framework for analysis used is randomisation-based or model- based produces puzzling difference in inferences. This can easily be shown by starting on the one hand with the randomisation philosophy associated with the Rothamsted school of inference and building up the analysis through the block + treatment structure approach associated with John Nelder’s theory of general balance (as implemented in GenStat®) or starting on the other hand with a plausible variance component approach through a mixed model. However, it can be shown that these differences are related not so much to modelling approach per se but to the questions one attempts to answer: ranging from testing whether there was a difference between treatments in the patients studied, to predicting the true difference for a future patient, via making inferences about the effect in the average patient.
This in turn yields interesting insight into the long-run debate over the use of fixed or random effect meta-analysis.
Some practical issues of analysis will also be covered in R and SAS®, in which languages some functions and macros to facilitate analysis have been written. It is concluded that n-of-1 hold great promise in investigating chronic rare diseases but that careful consideration of matters of purpose, design and analysis is necessary to make best use of them.
Acknowledgement
This work is partly supported by the European Union’s 7th Framework Programme for research, technological development and demonstration under grant agreement no. 602552. “IDEAL”
Practical Methods To Overcome Sample Size ChallengesnQuery
Watch the video at: https://www.statsols.com/webinars/practical-methods-to-overcome-sample-size-challenges
In this webinar hosted by Ronan Fitzpatrick - Head of Statistics and nQuery Lead Researcher at Statsols - we will examine some of the most common practical challenges you will experience while calculating sample size for your study. These challenges will be split into two categories:
1. Overcoming Sample Size Calculation Challenges
(Survival Analysis Example)
We will examine practical methods to overcome common sample size calculation issues by focusing in on one of the more complex areas for sample size determination; Survival analysis. We will cover difficulties and potential issues surrounding challenges such as:
Drop Out: How to deal with expected dropouts or censoring. We compare the simple loss-to-follow-up method and integrating a dropout process into the sample size model?
Planning Uncertainty: How best to deal with the inevitable uncertainty at the planning stage? We examine how best to apply a sensitivity analysis and Bayesian approaches to explore the uncertainty in your sample size calculations.
Choosing the Effect Size: Various approaches and interpretations exist for how to find the effect size value. We examine those contrasting interpretations and determine the best method and also how to deal with parameterization options.
2. Overcoming Study Design Challenges
(Vaccine Efficacy Example)
The Randomised Controlled Trial (RCT) is considered the gold standard in trial design in drug development. However, there are often practical impediments which mean that adjustments or pragmatic approaches are needed for some trials and studies.
We will examine practical methods how to overcome common study design challenges and how these affect your sample size calculations. In this webinar, we will use common issues in vaccine study design to examine difficulties surrounding issues such as:
Case-Control Analysis: We will examine how to deal with study constraints and how to deal with analyses done during an observational study.
Alternative Randomization Methods: How best to address randomization in your vaccine trial design when full randomization is difficult, expensive or impractical. We examine how sample size calculations are affected with cluster or Mendelian randomization.
Rare Events: How does an outcome being rare affect the types of study design and statistical methods chosen in your study.
Minimizing Risk In Phase II and III Sample Size CalculationnQuery
[ Watch Webinar: http://bit.ly/2thIgmi ]. In this free webinar, Head of Statistics at Statsols, Ronan Fitzpatrick, addresses the issues of reducing risk in Phase II/III sample size calculations. Topics covered will include:
Sample Size Determination For Different Trial Designs
Bayesian Sample Size Determination
Sample Size For Survival Analysis
& more
Innovative sample size methods for adaptive clinical trials webinar web ver...nQuery
View the video here:
https://www.statsols.com/webinar/innovative-sample-size-methods-for-adaptive-clinical-trials
Given the high failure rates and the increased costs of clinical trials, researchers need innovative design strategies to best optimize financial resources and reduce the risk to patients.
Adaptive designs are emerging as a way to reduce risk and cost associated with clinical trials. The FDA recently published guidance (Innovative Cures Act) and are actively encouraging sponsors to use Adaptive trials.
Adaptive design is a clinical trial design that allows adaptations or modifications to aspects of the trial after its initiation without undermining the validity and integrity of the trial.
In this webinar, Ronan will demonstrate nQuery's new Adaptive module focusing on Sample Size Re-Estimation & Group-Sequential Design.
In this webinar you will learn about:
The pros and cons of adaptive designs
Sample Size Re-Estimation
Group-Sequential Design
Conditional Power
Predictive Power
Optimizing Oncology Trial Design FAQs & Common IssuesnQuery
Optimizing Oncology Trial Design - FAQs & Common Issues
In this free webinar you will learn about
Endpoints
Models
Covariates, stratification and censoring issues
Adaptive design - complications and opportunities
Sample size determination
& more
In this free webinar we will offer guidance on how to optimize your oncology trial design. Specifically, we will examine the frequently asked questions and common issues that arise.
https://www.statsols.com/webinar/optimizing-oncology-trial-design
Innovative Strategies For Successful Trial Design - Webinar SlidesnQuery
Full webinar available here: https://www.statsols.com/webinar/innovative-strategies-for-successful-trial-design
[Webinar] Innovative Strategies For Successful Trial Design- In this free webinar, you will learn about:
- The challenges facing your trials
- How to calculate the correct sample size
- Worked examples including Mixed/Hierarchical Models
- Posterior Error
- Adaptive Designs For Survival
www.statsols.com
Extending A Trial’s Design Case Studies Of Dealing With Study Design IssuesnQuery
About the webinar
As trials increase in complexity and scope, there is a requirement for trial designs to reflect this.
From dealing with non-proportional hazards in survival analysis to dealing with cluster randomization, we examine how to deal with study design issues of complex trials.
In this free webinar, you will learn about:
Dealing with study design issues
Practical worked examples of
Non-proportional Hazards
Cluster Randomization
Three Armed Trials
Non-proportional Hazards
Non-proportional hazards and complex survival curves have become of increasing interest, due to being commonly seen in immunotherapy development. This has led to interest in assessing the robustness of standard methods and alternative methods that better adapt to deviations.
In this webinar, we look at methods proposed for complex survival curves and the weighted log-rank test as a candidate model to deal with a delayed survival effect.
Cluster Randomization
Cluster-randomized designs are often adopted when there is a high risk of contamination if cluster members were randomized individually. Stepped-wedge designs are useful in cases where it is difficult to apply a particular treatment to half of the clusters at the same time.
In this webinar, we introduce cluster randomization and stepped-wedge designs to provide an insight into the requirements of more complex randomization schedules.
Three Armed Trials
Non-inferiority testing is a common hypothesis test in the development of generic medicine and medical devices. The most common design compares the proposed non-inferior treatment to the standard treatment alone but this leaves uncertain if the treatment effect is the same as from previous studies. This “assay sensitivity” problem can be resolved by using a three arm trial which includes placebo alongside the new and reference treatments for direct comparison.
In this webinar we show a complete testing approach to this gold standard design and how to find the appropriate allocation and sample size for this study.
Duration - 60 minutes
Speaker: Ronan Fitzpatrick, Head of Statistics, Statsols
Cluster randomised trials with excessive cluster sizes: ethical and design im...Karla hemming
Investigators submitting funding applications strive for nominal levels of power to ensure their applications are competitive. If the number of clusters is limited this might mean large clusters are needed to achieve that power; but a slightly lower power might be achievable with a drastic reduction in cluster sizes. Alternatively, increasing the number of clusters minimally might mean the desired level of power is achievable, again with a drastic reduction in cluster sizes.
5 essential steps for sample size determination in clinical trials slidesharenQuery
In this free webinar hosted by nQuery Researcher & Statistician Eimear Keyes, we map out the 5 essential steps for sample size determination in clinical trials. At each step, Eimear will highlight the important function it plays and how to avoid the errors that will negatively impact your sample size determination and therefore your study.
Watch the Video: https://www.statsols.com/webinar/the-5-essential-steps-for-sample-size-determination
Sample size and how to calculate it
- Why sample size is important
- Alpha and beta errors
- Main outcome and Effect size
- Practical examples using Means-Proportions-Correlation- Confidence Interval
Poster Randomization Approach in Case-Based Reasoning: Case of Study of Mammo...Miled Basma Bentaiba
This document was presented on 8 May 2018 at the doctoral symposium at IFIP International Conference on Computational Intelligence and Its Applications (IFIP CIIA 2018).
An introduction to the stepped wedge cluster randomised trial, by Dr Karla Hemming for the CLAHRC West Midlands Scientific Advisory Group meeting, 9th June 2015, Birmingham, UK
Summary of current research on routine outcome measurement, feedback, the validity, reliability, and effectiveness of the ORS and SRS (or PCOMS Outcome Management System)
Talk given at ISCB 2016 Birmingham
For indications and treatments where their use is possible, n-of-1 trials represent a promising means of investigating potential treatments for rare diseases. Each patient permits repeated comparison of the treatments being investigated and this both increases the number of observations and reduces their variability compared to conventional parallel group trials.
However, depending on whether the framework for analysis used is randomisation-based or model- based produces puzzling difference in inferences. This can easily be shown by starting on the one hand with the randomisation philosophy associated with the Rothamsted school of inference and building up the analysis through the block + treatment structure approach associated with John Nelder’s theory of general balance (as implemented in GenStat®) or starting on the other hand with a plausible variance component approach through a mixed model. However, it can be shown that these differences are related not so much to modelling approach per se but to the questions one attempts to answer: ranging from testing whether there was a difference between treatments in the patients studied, to predicting the true difference for a future patient, via making inferences about the effect in the average patient.
This in turn yields interesting insight into the long-run debate over the use of fixed or random effect meta-analysis.
Some practical issues of analysis will also be covered in R and SAS®, in which languages some functions and macros to facilitate analysis have been written. It is concluded that n-of-1 hold great promise in investigating chronic rare diseases but that careful consideration of matters of purpose, design and analysis is necessary to make best use of them.
Acknowledgement
This work is partly supported by the European Union’s 7th Framework Programme for research, technological development and demonstration under grant agreement no. 602552. “IDEAL”
Practical Methods To Overcome Sample Size ChallengesnQuery
Watch the video at: https://www.statsols.com/webinars/practical-methods-to-overcome-sample-size-challenges
In this webinar hosted by Ronan Fitzpatrick - Head of Statistics and nQuery Lead Researcher at Statsols - we will examine some of the most common practical challenges you will experience while calculating sample size for your study. These challenges will be split into two categories:
1. Overcoming Sample Size Calculation Challenges
(Survival Analysis Example)
We will examine practical methods to overcome common sample size calculation issues by focusing in on one of the more complex areas for sample size determination; Survival analysis. We will cover difficulties and potential issues surrounding challenges such as:
Drop Out: How to deal with expected dropouts or censoring. We compare the simple loss-to-follow-up method and integrating a dropout process into the sample size model?
Planning Uncertainty: How best to deal with the inevitable uncertainty at the planning stage? We examine how best to apply a sensitivity analysis and Bayesian approaches to explore the uncertainty in your sample size calculations.
Choosing the Effect Size: Various approaches and interpretations exist for how to find the effect size value. We examine those contrasting interpretations and determine the best method and also how to deal with parameterization options.
2. Overcoming Study Design Challenges
(Vaccine Efficacy Example)
The Randomised Controlled Trial (RCT) is considered the gold standard in trial design in drug development. However, there are often practical impediments which mean that adjustments or pragmatic approaches are needed for some trials and studies.
We will examine practical methods how to overcome common study design challenges and how these affect your sample size calculations. In this webinar, we will use common issues in vaccine study design to examine difficulties surrounding issues such as:
Case-Control Analysis: We will examine how to deal with study constraints and how to deal with analyses done during an observational study.
Alternative Randomization Methods: How best to address randomization in your vaccine trial design when full randomization is difficult, expensive or impractical. We examine how sample size calculations are affected with cluster or Mendelian randomization.
Rare Events: How does an outcome being rare affect the types of study design and statistical methods chosen in your study.
Minimizing Risk In Phase II and III Sample Size CalculationnQuery
[ Watch Webinar: http://bit.ly/2thIgmi ]. In this free webinar, Head of Statistics at Statsols, Ronan Fitzpatrick, addresses the issues of reducing risk in Phase II/III sample size calculations. Topics covered will include:
Sample Size Determination For Different Trial Designs
Bayesian Sample Size Determination
Sample Size For Survival Analysis
& more
Bayesian Approaches To Improve Sample Size WebinarnQuery
Title: Bayesian Approaches To Improve Sample Size
Duration: 60 minutes
Speaker: Ronan Fitzpatrick, Head of Statistics, Statsols
In this webinar you'll learn about:
Bayesian Sample Size Determination: See how the growth of Bayesian analysis has helped transform our ideas about statistical inference and methodologies in clinical trials
Bayesian Assurance: Get an informative answer on how likely it is to see a “positive” outcome from the trial and then make better decisions on what trials to back
Posterior Credible Intervals and Mixed Bayesian Likelihood: Enable researchers to use prior information from pilot studies and other sources to make quicker and better decisions
Plus much more
Bayesian Assurance: Formalizing Sensitivity Analysis For Sample SizenQuery
Title: Bayesian Assurance: Formalizing Sensitivity Analysis For Sample Size
Duration: 60 minutes
Speaker: Ronan Fitzpatrick, Head of Statistics, Statsols
Watch Here: http://bit.ly/2ndRG4B
In this webinar you’ll learn about:
Benefits of Sensitivity Analysis: What does the researcher gain by conducting a sensitivity analysis?
Why isn't Sensitivity Analysis formalized: Why does sensitivity analysis still lack the type of formalized rules and grounding to make it a routine part of sample size determination in every field?
How Bayesian Assurance works: Using Bayesian Assurance provides key contextual information on what is likely to happen over the total range possible values rather than the small number of fixed points used in a sensitivity analysis
Elicitation & SHELF: How expert opinion is elicited and then how to integrate these opinions with each other plus prior data using the Sheffield Elicitation Framework (SHELF)
Why use in both Frequentist or Bayesian analysis: How and why these methods can be used for studies which will use Frequentist or Bayesian methods in their final analysis
Plus more
About the webinar
Flexible Clinical Trial Design | Survival, Stepped-Wedge & MAMS Designs
As clinical trials increase in complexity, the requirement is for trial designs to adapt to these complications.
From dealing with non-proportional hazards in survival analysis to creating seamless Phase II/III clinical trials, it is an exciting time to be involved in clinical trial design and analysis.
In this free webinar, we will explore a select few topics that highlight the additional flexibility available when designing modern clinical trials.
In this free webinar you will learn about:
Flexible Survival Analysis Designs
Non-proportional hazards and other complex survival curves have become of increasing interest, due to being commonly seen in immunotherapy development. This has led to interest in assessing the robustness of standard methods and alternative methods that better adapt to deviations.
In this webinar, we will look at power analysis assuming complex survival curves and the weighted log-rank test as one candidate model to deal with a delayed survival effect.
Stepped-Wedge designs
Cluster-randomized designs are often adopted when there is a high risk of contamination if cluster members were randomized individually. Stepped-wedge designs are useful in cases where it is difficult to apply a particular treatment to half of the clusters at the same time.
In this webinar, we will introduce stepped-wedge designs and provide an insight into the more complex, flexible randomization schedules available.
Multi-Arm Multi-Stage (MAMS)
MAMs designs provide the ability to assess more treatments in less time than could be done with a series of two-arm trials and can offer smaller sample size requirements when compared to that required for the equivalent number of two-arm trials.
In this webinar, we will look at the design of a Group Sequential MAMS design and explore its design requirements.
Duration - 60 minutes
Speaker: Ronan Fitzpatrick, Head of Statistics, Statsols
For more webinars check out https://www.statsols.com/webinars
Meta-analysis in Epidemiology is:
Useful tool for epidemiological studies which investigates the relationships between certain risk factors and disease.
Useful tool to improve animal well-being and productivity
Despite of a wealth of suitable studies it is relatively underutilized in animal and veterinary science.
Meta-analysis can provide reliable results about diseases occurrence, pattern and impact in livestock.
It is utmost essential to take benefit of this statistical tool for produce. more reliable estimates of concern effects in animal and veterinary science data.
Crimson Publishers: Reply To: Comments on "Transabdominal Preperitoneal (TAPP...CrimsonGastroenterology
Reply To: Comments on “Transabdominal Preperitoneal (TAPP) Versus Totally Extraperitoneal (TEP) for Laparoscopic Hernia Repair: A Meta-Analysis” by Feng Xian Wei in Gastroenterology Medicine & Research
Acute scrotum is a general term referring to an emergency condition affecting the contents or the wall of the scrotum.
There are a number of conditions that present acutely, predominantly with pain and/or swelling
A careful and detailed history and examination, and in some cases, investigations allow differentiation between these diagnoses. A prompt diagnosis is essential as the patient may require urgent surgical intervention
Testicular torsion refers to twisting of the spermatic cord, causing ischaemia of the testicle.
Testicular torsion results from inadequate fixation of the testis to the tunica vaginalis producing ischemia from reduced arterial inflow and venous outflow obstruction.
The prevalence of testicular torsion in adult patients hospitalized with acute scrotal pain is approximately 25 to 50 percent
NVBDCP.pptx Nation vector borne disease control programSapna Thakur
NVBDCP was launched in 2003-2004 . Vector-Borne Disease: Disease that results from an infection transmitted to humans and other animals by blood-feeding arthropods, such as mosquitoes, ticks, and fleas. Examples of vector-borne diseases include Dengue fever, West Nile Virus, Lyme disease, and malaria.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Prix Galien International 2024 Forum ProgramLevi Shapiro
June 20, 2024, Prix Galien International and Jerusalem Ethics Forum in ROME. Detailed agenda including panels:
- ADVANCES IN CARDIOLOGY: A NEW PARADIGM IS COMING
- WOMEN’S HEALTH: FERTILITY PRESERVATION
- WHAT’S NEW IN THE TREATMENT OF INFECTIOUS,
ONCOLOGICAL AND INFLAMMATORY SKIN DISEASES?
- ARTIFICIAL INTELLIGENCE AND ETHICS
- GENE THERAPY
- BEYOND BORDERS: GLOBAL INITIATIVES FOR DEMOCRATIZING LIFE SCIENCE TECHNOLOGIES AND PROMOTING ACCESS TO HEALTHCARE
- ETHICAL CHALLENGES IN LIFE SCIENCES
- Prix Galien International Awards Ceremony
Title: Sense of Smell
Presenter: Dr. Faiza, Assistant Professor of Physiology
Qualifications:
MBBS (Best Graduate, AIMC Lahore)
FCPS Physiology
ICMT, CHPE, DHPE (STMU)
MPH (GC University, Faisalabad)
MBA (Virtual University of Pakistan)
Learning Objectives:
Describe the primary categories of smells and the concept of odor blindness.
Explain the structure and location of the olfactory membrane and mucosa, including the types and roles of cells involved in olfaction.
Describe the pathway and mechanisms of olfactory signal transmission from the olfactory receptors to the brain.
Illustrate the biochemical cascade triggered by odorant binding to olfactory receptors, including the role of G-proteins and second messengers in generating an action potential.
Identify different types of olfactory disorders such as anosmia, hyposmia, hyperosmia, and dysosmia, including their potential causes.
Key Topics:
Olfactory Genes:
3% of the human genome accounts for olfactory genes.
400 genes for odorant receptors.
Olfactory Membrane:
Located in the superior part of the nasal cavity.
Medially: Folds downward along the superior septum.
Laterally: Folds over the superior turbinate and upper surface of the middle turbinate.
Total surface area: 5-10 square centimeters.
Olfactory Mucosa:
Olfactory Cells: Bipolar nerve cells derived from the CNS (100 million), with 4-25 olfactory cilia per cell.
Sustentacular Cells: Produce mucus and maintain ionic and molecular environment.
Basal Cells: Replace worn-out olfactory cells with an average lifespan of 1-2 months.
Bowman’s Gland: Secretes mucus.
Stimulation of Olfactory Cells:
Odorant dissolves in mucus and attaches to receptors on olfactory cilia.
Involves a cascade effect through G-proteins and second messengers, leading to depolarization and action potential generation in the olfactory nerve.
Quality of a Good Odorant:
Small (3-20 Carbon atoms), volatile, water-soluble, and lipid-soluble.
Facilitated by odorant-binding proteins in mucus.
Membrane Potential and Action Potential:
Resting membrane potential: -55mV.
Action potential frequency in the olfactory nerve increases with odorant strength.
Adaptation Towards the Sense of Smell:
Rapid adaptation within the first second, with further slow adaptation.
Psychological adaptation greater than receptor adaptation, involving feedback inhibition from the central nervous system.
Primary Sensations of Smell:
Camphoraceous, Musky, Floral, Pepperminty, Ethereal, Pungent, Putrid.
Odor Detection Threshold:
Examples: Hydrogen sulfide (0.0005 ppm), Methyl-mercaptan (0.002 ppm).
Some toxic substances are odorless at lethal concentrations.
Characteristics of Smell:
Odor blindness for single substances due to lack of appropriate receptor protein.
Behavioral and emotional influences of smell.
Transmission of Olfactory Signals:
From olfactory cells to glomeruli in the olfactory bulb, involving lateral inhibition.
Primitive, less old, and new olfactory systems with different path
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ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Knee anatomy and clinical tests 2024.pdfvimalpl1234
This includes all relevant anatomy and clinical tests compiled from standard textbooks, Campbell,netter etc..It is comprehensive and best suited for orthopaedicians and orthopaedic residents.
New Directions in Targeted Therapeutic Approaches for Older Adults With Mantl...i3 Health
i3 Health is pleased to make the speaker slides from this activity available for use as a non-accredited self-study or teaching resource.
This slide deck presented by Dr. Kami Maddocks, Professor-Clinical in the Division of Hematology and
Associate Division Director for Ambulatory Operations
The Ohio State University Comprehensive Cancer Center, will provide insight into new directions in targeted therapeutic approaches for older adults with mantle cell lymphoma.
STATEMENT OF NEED
Mantle cell lymphoma (MCL) is a rare, aggressive B-cell non-Hodgkin lymphoma (NHL) accounting for 5% to 7% of all lymphomas. Its prognosis ranges from indolent disease that does not require treatment for years to very aggressive disease, which is associated with poor survival (Silkenstedt et al, 2021). Typically, MCL is diagnosed at advanced stage and in older patients who cannot tolerate intensive therapy (NCCN, 2022). Although recent advances have slightly increased remission rates, recurrence and relapse remain very common, leading to a median overall survival between 3 and 6 years (LLS, 2021). Though there are several effective options, progress is still needed towards establishing an accepted frontline approach for MCL (Castellino et al, 2022). Treatment selection and management of MCL are complicated by the heterogeneity of prognosis, advanced age and comorbidities of patients, and lack of an established standard approach for treatment, making it vital that clinicians be familiar with the latest research and advances in this area. In this activity chaired by Michael Wang, MD, Professor in the Department of Lymphoma & Myeloma at MD Anderson Cancer Center, expert faculty will discuss prognostic factors informing treatment, the promising results of recent trials in new therapeutic approaches, and the implications of treatment resistance in therapeutic selection for MCL.
Target Audience
Hematology/oncology fellows, attending faculty, and other health care professionals involved in the treatment of patients with mantle cell lymphoma (MCL).
Learning Objectives
1.) Identify clinical and biological prognostic factors that can guide treatment decision making for older adults with MCL
2.) Evaluate emerging data on targeted therapeutic approaches for treatment-naive and relapsed/refractory MCL and their applicability to older adults
3.) Assess mechanisms of resistance to targeted therapies for MCL and their implications for treatment selection
Ethanol (CH3CH2OH), or beverage alcohol, is a two-carbon alcohol
that is rapidly distributed in the body and brain. Ethanol alters many
neurochemical systems and has rewarding and addictive properties. It
is the oldest recreational drug and likely contributes to more morbidity,
mortality, and public health costs than all illicit drugs combined. The
5th edition of the Diagnostic and Statistical Manual of Mental Disorders
(DSM-5) integrates alcohol abuse and alcohol dependence into a single
disorder called alcohol use disorder (AUD), with mild, moderate,
and severe subclassifications (American Psychiatric Association, 2013).
In the DSM-5, all types of substance abuse and dependence have been
combined into a single substance use disorder (SUD) on a continuum
from mild to severe. A diagnosis of AUD requires that at least two of
the 11 DSM-5 behaviors be present within a 12-month period (mild
AUD: 2–3 criteria; moderate AUD: 4–5 criteria; severe AUD: 6–11 criteria).
The four main behavioral effects of AUD are impaired control over
drinking, negative social consequences, risky use, and altered physiological
effects (tolerance, withdrawal). This chapter presents an overview
of the prevalence and harmful consequences of AUD in the U.S.,
the systemic nature of the disease, neurocircuitry and stages of AUD,
comorbidities, fetal alcohol spectrum disorders, genetic risk factors, and
pharmacotherapies for AUD.
micro teaching on communication m.sc nursing.pdfAnurag Sharma
Microteaching is a unique model of practice teaching. It is a viable instrument for the. desired change in the teaching behavior or the behavior potential which, in specified types of real. classroom situations, tends to facilitate the achievement of specified types of objectives.
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Ozempic: Preoperative Management of Patients on GLP-1 Receptor Agonists Saeid Safari
Preoperative Management of Patients on GLP-1 Receptor Agonists like Ozempic and Semiglutide
ASA GUIDELINE
NYSORA Guideline
2 Case Reports of Gastric Ultrasound
6. Sample Size Determination
(SSD) Review
SSD finds the appropriate sample size for
your study
Common metrics are statistical power, interval
width or cost
SSD seeks to balance ethical and practical
issues
A standard design requirement for regulatory
purposes
SSD is crucial to arrive at valid conclusions in
a study
8. 5 Essential Steps for Sample Size
1 Plan Study
Study question, primary outcome,
method
2 Specify Parameters
Significance Level, Standard deviation,
dispersion
3 Choose Effect Size
Expected/targeted difference, ratio or
effect size
4
Compute Sample Sample Size for specified metric such as
10. Sample Size Innovation
Overview
Sample Size Determination (SSD) has multiple
challenges to getting the appropriate sample
size.
These include uncertainty at planning stage
and lack of methods for newer statistical
methods and study designs.
In this webinar focus on three main areas of
interest:
1. Sample Size for Innovative Study Designs
2. Sample Size for Innovative Statistical Methods
11. Sample Size Innovation
Examples
1. Sample Size for Innovative Study Designs
Examples: Adaptive/seamless designs and causal
studies
2. Sample Size for Innovative Statistical
Methods
Examples: Bayesian methods, mixed and
generalized models
3. Innovative Methods in Sample Size
Determination
13. In 2017, 90% of organizations with clinical trials
approved
by the FDA used nQuery for sample size and power
calculation
14. nQuery Timeline
nTerim introduced
G.S.T
C.R.T
Count Data
MANOVA / ANOVA
Launch of nQuery
Advanced
New platform = Modern
all-in-one software
solution
New Bayesian Module
Survival Focus
IQ/OQ Tools
52 new Core
Tables
20 new Bayes
Tables
-Launch of nQuery
Advisor 1.0
Developed by Dr.
Janet D. Elashoff
-Contiguous
Innovation and
releases
2007 - 2016 2017 Spring 20181996-2007
15. nQuery Spring 2018 Update
Initial release focused on Survival & Bayesian tables.
April release adds 72 new tables in following areas:
New Bayes tables in
April update
New tables in April
update
Epidemiology Non-inferiority/
Equivalence
Correlation/ROC
Bayesian
Sample Size
16. Mendelian Randomization Studies
Mendelian Randomization
(MR) uses underlying
genetic variation to make
causal inferences
Uses genes with well
understood link between
polymorphism(s) and
relevant intermediate
phenotype
Note that gene must be
indirectly related to
exposure of interest
MR uses gene(s) as an
Source: S. Burgess et. al.
(2012)
17. Mendelian Randomization Example
“We computed F statistics
and R 2 values (the proportion of
variation in height and BMI
explained by the genetic risk
score) from the linear regression
to evaluate the strength of the
genetic risk score instruments in
a population of men at increased
risk of cancer. We had 82 and
78 % power to detect an odds
ratio of 1.12 and 1.25 for the
effects of height and BMI on
prostate cancer risk, assuming a
sample size of 41,062 and that
the genetic risk scores explained
6.31 and 1.46 % of the variation
Source: Springer.com
Parameter Value
Significance Level (Two-
Sided)
0.05
Positive Outcome
Proportion
0.5
Odds Ratio 1.12/1.25
Variance Explained 0.0631/0.01
46
18. Sample Size for Incidence Rates
(Counts)
Incidences rates (a.k.a
counts) are a study outcome
where measuring rate of
event per unit time
Traditional methods were
normal approximations or
Poisson model
Negative Binomial or Quasi-
Poisson model increasingly
popular
Sample Size methods for NB
and Q-P being actively
Source: R. Lehr
(1992)
Source: H. Zhu & H. Lakkis
(2014)
Source: Y. Tang (2015)
19. Negative Binomial Regression
Example
“On the basis of previous
studies of fluticasone
propionate–salmeterol
combinations we assumed a
yearly exacerbation rate with
vilanterol of 1·4 and a
dispersion parameter of 0·7.
Thus, we calculated that a
sample size of 390 assessable
patients per group in each
study would provide each study
with 90% power to detect a 25%
reduction in exacerbations in
the fluticasone furoate and
vilanterol groups versus the
Source: TheLancet.com
Parameter Value
Significance Level (Two-Sided) 0.05
Control Incidence Rate (per year) 1.4
Rate Ratio 0.75
Exposure Time (Years) 0.7
Dispersion Parameter 74
Power (%) 90%
20. Assurance for Clinical Trials
Assurance (a.k.a “Bayesian
Power”) is the unconditional
probability of significance
given a prior
Focus on methods proposed
by O’Hagan et al. (2005)
Assurance is the expectation
of the power averaged over
a prior distribution for the
effect
Often framed the “true
probability of success” of a
trial
Can be considered as a
Bayesian analogue to
Source: O’Hagan
(2005)
21. Survival Assurance Example
“Using an unstratified log-rank test at
the one-sided 2.5% significance level, a
total of 282 events would allow 92.6%
power to demonstrate a 33% risk
reduction (hazard ratio for RAD/placebo
of about 0.67, as calculated from an
anticipated 50% increase in median PFS,
from 6 months in placebo arm to 9
months in the RAD001 arm). With a
uniform accrual of approximately 23
patients per month over 74 weeks and a
minimum follow up of 39 weeks, a total
of 352 patients would be required to
obtain 282 PFS events, assuming an
exponential progression-free survival
distribution with a median of 6 months
in the Placebo arm and of 9 months in
RAD001 arm. With an estimated 10% lost
to follow up patients, a total sample size
of 392 patients should be randomized.”
Source: nejm.org
Parameter Value
Significance Level (One-Sided) 0.025
Placebo Median Survival
(months)
6
Everolimus Median Survival
(months)
9
Hazard Ratio 0.6666
7
Accrual Period (Weeks) 74
Minimum Follow-Up (Weeks) 39
22. Continual Reassessment Method
(CRM)
CRM is increasingly popular
design for Phase I MTD trials
Provides better results for
MTD over 3+3 design and
allows potential efficacy
assessment
Small N and minimal prior
info requires simulations for
planning
nQuery provides starting
approximation for sample
size from YK Cheung (2013)
Source: Y.K. Cheung
(2011)
23. Continual Reassessment Example
“To provide a quick estimate of
budget (that is, n) for a dose
finding study of PTEN-long
monotherapy in patients with
pancreatic cancer, we calculated
the required sample size … In the
trial, the MTD was defined with
target θ = 0.25. The starting dose
of the trial would be determined
based on a prior pharmacokinetic
study, and would be the third dose
level in a panel of K = 5 test doses.
To obtain an average PCS of a* =
0.6 under R = 1.8, we obtained b*
= 0.648 and ñ(b*) = 31.6. Thus,
the sample size of the trial was set
Source:
journals.sagepub.com
Parameter Value
Probability of Success 60%
Target Dose Toxicity Rate 0.25
Number of Dose Levels 9
Effect Size (Odds Ratio) 0.6666
7
25. Discussion and Conclusions
Much Interest in finding SSD solutions for
new methods
Push to allow more innovation in study planning
and design
Continuing interest in dealing with complex
SSD issues
Uncertainty is intrinsic part of SSD since at
planning stage
Large eco-system of potential solutions for
your study
27. References
Burgess, S. (2014). Sample size and power calculations in Mendelian randomization with a single
instrumental variable and a binary outcome. International Journal of Epidemiology, 43, 922-929
Davies, N. M., et. al. (2015). The effects of height and BMI on prostate cancer incidence and mortality: a
Mendelian randomization study in 20,848 cases and 20,214 controls from the PRACTICAL consortium.
Cancer Causes & Control, 26(11), 1603-1616.
Tang, Y. (2017). Sample size for comparing negative binomial rates in noninferiority and equivalence trials
with unequal follow-up times. Journal of biopharmaceutical statistics, 1-17.
Dransfield, M. T., et. al. (2013). Once-daily inhaled fluticasone furoate and vilanterol versus vilanterol only
for prevention of exacerbations of COPD: two replicate double-blind, parallel-group, randomised
controlled trials. The lancet Respiratory medicine, 1(3), 210-223.
O'Hagan, A., Stevens, J. W., & Campbell, M. J. (2005). Assurance in clinical trial design. Pharmaceutical
Statistics, 4(3), 187-201.
Yao, J. C., et. al. (2011). Everolimus for advanced pancreatic neuroendocrine tumors. New England Journal
of Medicine, 364(6), 514-523.
Kuen Cheung, Y. (2013), Sample size formulae for the Bayesian continual reassessment method, Clinical
Trials: Journal of the Society for Clinical Trials, 10(6), 852-861.
Editor's Notes
More detail available on our website via a whitepaper.
Point 1:
http://rsos.royalsocietypublishing.org/content/1/3/140216 -> Screening problem analogy.
Type S Error = Sign Error i.e. sign of estimate is different than actual population value
Type M Error = Magnitude Error i.e. estimate is order of magnitude different than actual value
Point 2:
Know we have only 100 subjects available. Need to know what power will this give us, i.e. is there enough power to justify even doing the study.
Stage III clinical trials constitute 90% of trial costs, vital to reduce waste and ensure can fulfil goal.
Point 3:
Sample Size requirements described in ICH Efficacy Guidelines 9: STATISTICAL PRINCIPLES FOR CLINICAL TRIALS
See FDA/NIH draft protocol template here: http://osp.od.nih.gov/sites/default/files/Protocol_Template_05Feb2016_508.pdf (Section 10.5)
Nature Statistical Checklist: http://www.nature.com/nature/authors/gta/Statistical_checklist.doc
Point 4:
In Cohen’s (1962) seminal power analysis of the journal of Abnormal and Social Psychology he concluded that over half of the published studies were insufficiently powered to result in statistical significance for the main hypothesis. Many journals (e.g. Nature) now require that authors submit power estimates for their studies.
Power/Sample size one of areas highlighted when discussing “crisis of reproducibility” (Ioannidis). Relatively easy fix compared to finding p-hacking etc.