A systematic review of the reporting of Data Monitoring Committees' roles, interim analysis and early termination in pediatric clinical trials

Stochastic curtailment tests for phase II trial with time-to-event outcome using the concept of relative time in the case of non-proportional hazards

As part of the drug development process, interim analysis is frequently used to design efficient phase II clinical trials. A stochastic curtailment framework is often deployed wherein a decision to continue or curtail the trial is taken at each interim look based on the likelihood of observing a positive or negative treatment effect if the trial were to continue to its anticipated end. Thus, curtailment can take place due to evidence of early efficacy or futility. Traditionally, in the case of time-to-event endpoints, interim monitoring is conducted in a two-arm clinical trial using the log-rank test, often with the assumption of proportional hazards. However, when this is violated, the log-rank test may not be appropriate, resulting in loss of power and subsequently inaccurate sample sizes. In this paper, we propose stochastic curtailment methods for two-arm phase II trial with the flexibility to allow non-proportional hazards. The proposed methods are built utilizing the concept of relative time assuming that the survival times in the two treatment arms follow two different Weibull distributions. Three methods - conditional power, predictive power and Bayesian predictive probability - are discussed along with corresponding sample size calculations. The monitoring strategy is discussed with a real-life example.

Developments in the Design, Conduct, and Reporting of Child Health Trials

To identify priority areas to improve the design, conduct, and reporting of pediatric clinical trials, the international expert network, Standards for Research (StaR) in Child Health, was assembled and published the first 6 Standards in Pediatrics in 2012. After a recent review summarizing the 247 publications by StaR Child Health authors that highlight research practices that add value and reduce research "waste," the current review assesses the progress in key child health trial methods areas: consent and recruitment, containing risk of bias, roles of data monitoring committees, appropriate sample size calculations, outcome selection and measurement, and age groups for pediatric trials. Although meaningful change has occurred within the child health research ecosystem, measurable progress is still disappointingly slow. In this context, we identify and review emerging trends that will advance the agenda of increased clinical usefulness of pediatric trials, including patient and public engagement, Bayesian statistical approaches, adaptive designs, and platform trials. We explore how implementation science approaches could be applied to effect measurable improvements in the design, conducted, and reporting of child health research.

A Decade of Efforts to Add Value to Child Health Research Practices

OBJECTIVE

To identify practices that add value to improve the design, conduct, and reporting of child health research and reduce research waste.

STUDY DESIGN

In order to categorize the contributions of members of Standards for Research (StaR) in Child Health network, we developed a novel Child Health Improving Research Practices (CHIRP) framework comprised of 5 domains meant to counteract avoidable child health research waste and improve quality: 1) address research questions relevant to children, their families, clinicians, and researchers; 2) apply appropriate research design, conduct and analysis; 3) ensure efficient research oversight and regulation; 4) Provide accessible research protocols and reports; and 5) develop unbiased and usable research reports, including 17 responsible research practice recommendations. All child health research relevant publications by the 48 original StaR standards' authors over the last decade were identified, and main topic areas were categorized using this framework.

RESULTS

A total of 247 publications were included in the final sample: 100 publications (41%) in domain 1 (3 recommendations), 77 publications (31%) in domain 2 (3), 35 publications (14%) in domain 3 (4), 20 publications (8%) in domain 4 (4), and 15 publications (6%) in domain 5 (3). We identified readily implementable "responsible" research practices to counter child health research waste and improve quality, especially in the areas of patients and families' engagement throughout the research process, developing Core Outcome Sets, and addressing ethics and regulatory oversight issues.

CONCLUSION

While most of the practices are readily implementable, increased awareness of methodological issues and wider guideline uptake is needed to improve child health research. The CHIRP Framework can be used to guide responsible research practices that add value to child health research.

Data monitoring committees in pediatric randomized controlled trials registered in ClinicalTrials.gov

BACKGROUND

Data monitoring committees advise on clinical trial conduct through appraisal of emerging data to ensure participant safety and scientific integrity. While consideration of their use is recommended for trials performed with vulnerable populations, previous research has shown that data monitoring committees are reported infrequently in publications of pediatric randomized controlled trials. We aimed to assess the frequency of reported data monitoring committee adoption in ClinicalTrials.gov registry records and to examine the influence of key trial characteristics.

METHODS

We conducted a cross-sectional data analysis of all randomized controlled trials performed exclusively in a pediatric population and registered in ClinicalTrials.gov between 2008 and 2021. We used the Access to Aggregate Content of ClinicalTrials.gov database to retrieve publicly available information on trial characteristics and data on safety results. Abstracted data included reported trial design and conduct parameters, population and intervention characteristics, reasons for prematurely halting, serious adverse events, and mortality outcomes. We performed descriptive analyses on the collected data and explored the influence of clinical, methodological, and operational trial characteristics on the reported adoption of data monitoring committees.

RESULTS

We identified 13,928 pediatric randomized controlled trial records, of which 39.7% reported adopting a data monitoring committee, 49.0% reported not adopting a data monitoring committee, and 11.3% did not answer on this item. While the number of registered pediatric trials has been increasing since 2008, we found no clear time trend in the reported adoption of data monitoring committees. Data monitoring committees were more common in multicenter trials (50.6% vs 36.9% for single-center), multinational trials (60.2% vs 38.7% for single-country), National Institutes of Health-funded (60.3% vs 40.1% for industry-funded or 37.5% for other funders), and placebo-controlled (47.6% vs 37.5% for other types of control groups). Data monitoring committees were also more common among trials enrolling younger participants, trials employing blinding techniques, and larger trials. Data monitoring committees were more common in trials with at least one serious adverse event (52.6% vs 38.4% for those without) as well as for trials with reported deaths (70.3% vs 38.9% for trials without reported deaths). In all, 4.9% were listed as halted prematurely, most often due to low accrual rates. Trials with a data monitoring committee were more often halted for reasons related to scientific data than trials without a data monitoring committee (15.7% vs 7.3%).

CONCLUSION

According to registry records, the use of data monitoring committees in pediatric randomized controlled trials was more frequent than previously reported in reviews of published trial reports. The use of data monitoring committees varied across key clinical and trial characteristics based on which their use is recommended. Data monitoring committees may still be underutilized in pediatric trials, and reporting of this item could be improved.

Point estimation for adaptive trial designs II: Practical considerations and guidance

In adaptive clinical trials, the conventional end-of-trial point estimate of a treatment effect is prone to bias, that is, a systematic tendency to deviate from its true value. As stated in recent FDA guidance on adaptive designs, it is desirable to report estimates of treatment effects that reduce or remove this bias. However, it may be unclear which of the available estimators are preferable, and their use remains rare in practice. This article is the second in a two-part series that studies the issue of bias in point estimation for adaptive trials. Part I provided a methodological review of approaches to remove or reduce the potential bias in point estimation for adaptive designs. In part II, we discuss how bias can affect standard estimators and assess the negative impact this can have. We review current practice for reporting point estimates and illustrate the computation of different estimators using a real adaptive trial example (including code), which we use as a basis for a simulation study. We show that while on average the values of these estimators can be similar, for a particular trial realization they can give noticeably different values for the estimated treatment effect. Finally, we propose guidelines for researchers around the choice of estimators and the reporting of estimates following an adaptive design. The issue of bias should be considered throughout the whole lifecycle of an adaptive design, with the estimation strategy prespecified in the statistical analysis plan. When available, unbiased or bias-reduced estimates are to be preferred.

Results Reporting and Early Termination of Childhood Obesity Trials Registered on ClinicalTrials.gov

Objective

Childhood obesity is one of the most severe challenges of public health in the twenty-first century and may increase the risk of various physical and psychological diseases in adulthood. The prevalence and predictors of unreported results and premature termination in pediatric obesity research are not clear. We aimed to characterize childhood obesity trials registered on ClinicalTrials.gov and identify features associated with early termination and lack of results reporting.

Methods

Records were downloaded and screened for all childhood obesity trials from the inception of ClinicalTrials.gov to July 29, 2021. We performed descriptive analyses of characteristics, Cox regression for early termination, and logistic regression for lack of results reporting.

Results

We identified 1,312 trials registered at ClinicalTrials.gov. Among clinicalTrials.gov registered childhood obesity-related intervention trials, trial unreported results were 88.5 and 4.3% of trials were prematurely terminated. Additionally, the factors that reduced the risk of unreported outcomes were US-registered clinical studies and drug intervention trials. Factors associated with a reduced risk of early termination are National Institutes of Health (NIH) or other federal agency funding and large trials.

Conclusion

The problem of unreported results in clinical trials of childhood obesity is serious. Therefore, timely bulletin of the results and reasons for termination remain urgent aims for childhood obesity trials.

The adaptive designs CONSORT extension (ACE) statement: a checklist with explanation and elaboration guideline for reporting randomised trials that use an adaptive design

Adaptive designs (ADs) allow pre-planned changes to an ongoing trial without compromising the validity of conclusions and it is essential to distinguish pre-planned from unplanned changes that may also occur. The reporting of ADs in randomised trials is inconsistent and needs improving. Incompletely reported AD randomised trials are difficult to reproduce and are hard to interpret and synthesise. This consequently hampers their ability to inform practice as well as future research and contributes to research waste. Better transparency and adequate reporting will enable the potential benefits of ADs to be realised.This extension to the Consolidated Standards Of Reporting Trials (CONSORT) 2010 statement was developed to enhance the reporting of randomised AD clinical trials. We developed an Adaptive designs CONSORT Extension (ACE) guideline through a two-stage Delphi process with input from multidisciplinary key stakeholders in clinical trials research in the public and private sectors from 21 countries, followed by a consensus meeting. Members of the CONSORT Group were involved during the development process.The paper presents the ACE checklists for AD randomised trial reports and abstracts, as well as an explanation with examples to aid the application of the guideline. The ACE checklist comprises seven new items, nine modified items, six unchanged items for which additional explanatory text clarifies further considerations for ADs, and 20 unchanged items not requiring further explanatory text. The ACE abstract checklist has one new item, one modified item, one unchanged item with additional explanatory text for ADs, and 15 unchanged items not requiring further explanatory text.The intention is to enhance transparency and improve reporting of AD randomised trials to improve the interpretability of their results and reproducibility of their methods, results and inference. We also hope indirectly to facilitate the much-needed knowledge transfer of innovative trial designs to maximise their potential benefits. In order to encourage its wide dissemination this article is freely accessible on the BMJ and Trials journal websites."To maximise the benefit to society, you need to not just do research but do it well" Douglas G Altman.

The Adaptive designs CONSORT Extension (ACE) statement: a checklist with explanation and elaboration guideline for reporting randomised trials that use an adaptive design

Adaptive designs (ADs) allow pre-planned changes to an ongoing trial without compromising the validity of conclusions and it is essential to distinguish pre-planned from unplanned changes that may also occur. The reporting of ADs in randomised trials is inconsistent and needs improving. Incompletely reported AD randomised trials are difficult to reproduce and are hard to interpret and synthesise. This consequently hampers their ability to inform practice as well as future research and contributes to research waste. Better transparency and adequate reporting will enable the potential benefits of ADs to be realised.This extension to the Consolidated Standards Of Reporting Trials (CONSORT) 2010 statement was developed to enhance the reporting of randomised AD clinical trials. We developed an Adaptive designs CONSORT Extension (ACE) guideline through a two-stage Delphi process with input from multidisciplinary key stakeholders in clinical trials research in the public and private sectors from 21 countries, followed by a consensus meeting. Members of the CONSORT Group were involved during the development process.The paper presents the ACE checklists for AD randomised trial reports and abstracts, as well as an explanation with examples to aid the application of the guideline. The ACE checklist comprises seven new items, nine modified items, six unchanged items for which additional explanatory text clarifies further considerations for ADs, and 20 unchanged items not requiring further explanatory text. The ACE abstract checklist has one new item, one modified item, one unchanged item with additional explanatory text for ADs, and 15 unchanged items not requiring further explanatory text.The intention is to enhance transparency and improve reporting of AD randomised trials to improve the interpretability of their results and reproducibility of their methods, results and inference. We also hope indirectly to facilitate the much-needed knowledge transfer of innovative trial designs to maximise their potential benefits.

Reporting of data monitoring committees and adverse events in paediatric trials: a descriptive analysis

OBJECTIVES

For 300 paediatric trials, we evaluated the reporting of: a data monitoring committee (DMC); interim analyses, stopping rules and early stopping; and adverse events and harm-related endpoints.

METHODS

For this cross-sectional evaluation, we randomly selected 300 paediatric trials published in 2012 from the Cochrane Central Register of Controlled Trials. We collected data on the reporting of a DMC; interim analyses, stopping rules and early stopping; and adverse events and harm-related endpoints. We reported the findings descriptively and stratified by trial characteristics.

RESULTS

Eighty-five (28%) of the trials investigated drugs, and 18% (n=55/300) reported a DMC. The reporting of a DMC was more common among multicentre than single centre trials (n=41/132, 31% vs n=14/139, 10%, p<0.001) and industry-sponsored trials compared with those sponsored by other sources (n=16/50, 32% vs n=39/250, 16%, p=0.009). Trials that reported a DMC enrolled more participants than those that did not (median [range]): 224 (10-60480) vs 91 (10-9528) (p<0.001). Only 25% of these trials reported interim analyses, and 42% reported stopping rules. Less than half (n=143/300, 48%) of trials reported on adverse events, and 72% (n=215/300) reported on harm-related endpoints. Trials that reported a DMC compared with those that did not were more likely to report adverse events (n=43/55, 78% vs 100/245, 41%, p<0.001) and harm-related endpoints (n=52/55, 95% vs. 163/245, 67%, p<0.001). Only 32% of drug trials reported a DMC; 18% and 19% did not report on adverse events or harm-related endpoints, respectively.

CONCLUSIONS

The reporting of a DMC was infrequent, even among drug trials. Few trials reported stopping rules or interim analyses. Reporting of adverse events and harm-related endpoints was suboptimal.

Premature Discontinuation of Pediatric Randomized Controlled Trials: A Retrospective Cohort Study

OBJECTIVES

To determine the proportion of pediatric randomized controlled trials (RCTs) that are prematurely discontinued, examine the reasons for discontinuation, and compare the risk for recruitment failure in pediatric and adult RCTs.

STUDY DESIGN

A retrospective cohort study of RCTs approved by 1 of 6 Research Ethics Committees (RECs) in Switzerland, Germany, and Canada between 2000 and 2003. We recorded trial characteristics, trial discontinuation, and reasons for discontinuation from protocols, corresponding publications, REC files, and a survey of trialists.

RESULTS

We included 894 RCTs, of which 86 enrolled children and 808 enrolled adults. Forty percent of the pediatric RCTs and 29% of the adult RCTs were discontinued. Slow recruitment accounted for 56% of pediatric RCT discontinuations and 43% of adult RCT discontinuations. Multivariable logistic regression analyses suggested that pediatric RCT was not an independent risk factor for recruitment failure after adjustment for other potential risk factors (aOR, 1.22; 95% CI, 0.57-2.63). Independent risk factors were acute care setting (aOR, 4.00; 95% CI, 1.72-9.31), nonindustry sponsorship (aOR, 4.45; 95% CI, 2.59-7.65), and smaller planned sample size (aOR, 1.05; 95% CI 1.01-1.09, in decrements of 100 participants).

CONCLUSION

Forty percent of pediatric RCTs were discontinued prematurely, owing predominately to slow recruitment. Enrollment of children was not an independent risk factor for recruitment failure.

Reporting of data monitoring boards in publications of randomized clinical trials is often deficient: ACTTION systematic review

OBJECTIVE

To examine whether primary reports of randomized clinical trials (RCTs) in six high-impact, general medical journals reported (1) whether or not a Data Monitoring Committee/Data and Safety Monitoring Board (DMC/DSMB) was used and (2) the composition of the responsibilities of the reported DSMB/DMCs.

STUDY DESIGN AND SETTING

Systematic review of RCTs published in 2014 in Annals of Internal Medicine, BMJ, NEJM, JAMA, JAMA Internal Medicine, and Lancet.

RESULTS

Of the 294 articles identified, 174 (59%) mentioned using a DMC/DSMB. Of these 174, 126 (72%) indicated at least one responsibility of the DMC/DSMB, 26% listed the names of the DMC/DSMB members, and another 14% listed both their names and affiliations. Only one article stated that a DSMB was not used. The remaining 119 articles did not report whether or not a DMC/DSMB was used, although 59 had previously stated in a clinical trials registry entry or a published protocol that a DMC/DSMB was to be used.

CONCLUSIONS

Considering the major role that DMC/DSMBs play in protecting participant safety, data quality, and interim analyses in RCTs, we recommend that authors of publications of RCTs report whether a DMC/DSMB was used and the responsibilities and members of DMC/DSMBs to increase transparency regarding study conduct.

Reporting on data monitoring committees in neonatal randomised controlled trials is inconsistent

AIM

To evaluate the reported use of data monitoring committees (DMCs), the frequency of interim analysis, prespecified stopping rules and early trial termination in neonatal randomised controlled trials (RCTs).

METHODS

We reviewed neonatal RCTs published in four high-impact general medical journals, specifically looking at safety issues including documented involvement of a DMC, stated interim analysis, stopping rules and early trial termination. We searched all journal issues over an 11-year period (2003-2013) and recorded predefined parameters on each item for RCTs meeting inclusion criteria.

RESULTS

Seventy neonatal trials were identified in four general medical journals: Lancet, New England Journal of Medicine (NEJM), British Medical Journal and Journal of American Medical Association. A total of 43 (61.4%) studies reported the presence of a DMC, 36 (51.4%) explicitly mentioned interim analysis, stopping rules were reported in 15 (21.4%) RCTs and seven (10%) trials were terminated early. The NEJM most frequently reported these parameters compared to the other three journals reviewed.

CONCLUSION

While the majority of neonatal RCTs report on DMC involvement and interim analysis, there is still scope for improvement. Clear documentation of safety-related issues should be a central component of reporting in neonatal trials involving newborn infants.

Moving toward a paradigm shift in the regulatory requirements for pediatric medicines

Over the past two decades, there has been growing concern over the lack of proper medication for children. This review attempts to evaluate the current progress of EU Pediatric Regulation made since 2007. The lack of properly evaluated pediatric medication has for long been a source of concern in the European Union. The drugs that were used in the past were often not properly evaluated, and dosage was arbitrarily calculated. Therefore, it was necessary to establish the Pediatric Regulation (EC no. 1901/2006) in the EU which would mandate research for pediatric drugs. Current legislations in place not only require mandatory research by pharma industry but also have guidelines to direct the quality of pediatric research performed. The main aim of this regulation was to advance high-quality research and development of pediatric drugs, thereby increasing the availability of safe and effective drugs for children. It also aimed to improve the information available on existing pediatric drugs. It has been 9 years since the pediatric regulation was framed. The pharma industry now sees pediatric research as an integral process of development. Drug companies which develop plans for a new drug, new form of drug, new indication, or new route of administration for adults are obliged to integrate in their development plan similar research for pediatric populations as well.

CONCLUSION

It is hoped that the implementation of the current legislation will be reflected better in the future by the marketing of better and safer drugs for the pediatric population. The upcoming assessment to the European Commission in 2017 will further inform us on the impact after 10 years implementation of the legislation. What is Known: • The lack of properly evaluated pediatric medication has for long been a source of concern in the European Union. • Therefore, it was necessary to establish the EU Pediatric Regulation which would mandate research for pediatric drugs. What is New: • It has been 9 years since the pediatric regulation was framed, and the teething problems are slowly being overcome and the regulation is being used with increasing confidence. • As the Regulation is due for revision in 2017, this paper gives a current perspective on the impact of the regulation on availability and access to medicine for children.

StaR Child Health: developing evidence-based guidance for the design, conduct and reporting of paediatric trials

There has been a huge upsurge in clinical research in children in the last decade, stimulated in England by dedicated research infrastructure and support through the National Institute for Health Research. This infrastructure offering research design, expert review, trial management, research nurse, data support and dedicated facilities enables paediatricians to conduct more and better research. The challenge is how to design and conduct trials that will make a real difference to children's health. Standards for Research (StaR) in Child Health was founded in 2009 to address the paucity and shortcomings of paediatric clinical trials. This global initiative involves methodologists, clinicians, patient advocacy groups and policy makers dedicated to developing practical, evidence-based standards for enhancing the reliability and relevance of paediatric clinical research. In this overview, we highlight the contribution of StaR to this agenda, describe the international context, and suggest how StaR's future plans could be integrated with new and existing support for research.

Mask versus nasal tube for stabilization of preterm infants at birth: a randomized controlled trial

OBJECTIVE

Positive-pressure ventilation (PPV) using a manual ventilation device and a face mask is recommended for compromised newborn infants in the delivery room (DR). Mask ventilation is associated with airway obstruction and leak. A nasal tube is an alternative interface, but its safety and efficacy have not been tested in extremely preterm infants.

METHODS

An unblinded randomized controlled trial was conducted in Australia, and the Netherlands. Infants were stratified by gestational age (24-25/26-29 weeks) and center. Immediately before birth infants were randomly assigned to receive PPV and/or continuous positive airway pressure with either a nasal tube or a size 00 soft, round silicone mask. Resuscitation protocols were standardized; respiratory support was provided using a T-piece device commencing in room air. Criteria for intubation included need for cardiac compressions, apnea, continuous positive airway pressure >7 cm H2O, and fraction of inspired oxygen >0.4. Primary outcome was endotracheal intubation in the first 24 hours from birth.

RESULTS

Three hundred sixty-three infants were randomly assigned; the study terminated early on the grounds of futility. Baseline variables were similar between groups. Intubation rates in the first 24 hours were 54% and 55% in the nasal tube and face mask groups, respectively (odds ratio: 0.97; 95% confidence interval: 0.63-1.50). There were no important differences in any of the secondary outcomes within the whole cohort or between the 2 gestational age subgroups.

CONCLUSIONS

In infants at <30 weeks' gestation receiving PPV in the DR, there were no differences in short-term outcomes using the nasal tube compared with the face mask.

Safety methodology in pediatric psychopharmacology trials

In recent years, there has been an increase in pediatric clinical trials as the result of an identified need for greater research with this population. Given the potential risks, and the vulnerability of the population, there has also been an identified need for greater safety elicitation and monitoring in pediatric psychopharmacology trials, for example, through the use of a data and safety monitoring board (DSMB). However, research indicates that pediatric trials and psychiatric trials are less likely to use a DSMB. The rationale for the current study was to determine what safety methodologies have been reported in pediatric psychopharmacology trials over the past 10 years. A literature review was conducted of all pediatric psychopharmacology trials published since 2001. Results indicated that the most common elicitation method was collecting laboratory information and vital signs. Six percent of trials solely relied on spontaneous reporting of adverse events, and only 11.8% reported using a DSMB. These results suggest that elicitation methods and use of DSMBs are still low. Practical considerations, affected stakeholders, and barriers are discussed. Recommendations for moving forward include the use of multiple elicitation methods and automatic requirement of a DSMB for pediatric psychopharmacology trials, required completion of a standardized safety reporting form, and engaging multiple interested parties in these processes.

StaR Child Health: developing evidence-based guidance for the design, conduct, and reporting of pediatric trials

Standards for Research in (StaR) Child Health was founded in 2009 to address the paucity and shortcomings of pediatric clinical trials. This initiative involves international experts who are dedicated to developing practical, evidence-based standards to enhance the reliability and relevance of pediatric clinical research. Through a systematic "knowledge to action" plan, StaR Child Health will make efforts to improve and expand the evidence base for child health across the world.

Data monitoring committees, interim analysis and early termination in paediatric trials

AIM

To evaluate whether paediatric randomized clinical trials (RCTs) adopt recent guidance on Data Monitoring Committees (DMCs), interim analysis and early termination.

METHODS

We reviewed paediatric RCTs that reported on DMCs, interim analysis or early termination, published in eight general medical and paediatric journals (2005-2007). We searched full-text databases for eligible trials and recorded predefined parameters on each item. Reported activities were compared with current scientific guidance.

RESULTS

A total of 110 of 648 paediatric trials (17%) reported on DMC, interim analysis or early stopping. Various approaches for convening a DMC were identified; information on DMC composition and independence was limited. Strict predefined statistical stopping 'rules' were reported in 10 of 23 trials, and interim analyses were more frequently performed on efficacy than on safety outcomes (39/45 vs 27/45). No adjustment for repeated testing was reported in 11 of 33 trials reporting monitoring methods and in 7 of 17 early terminated trials. Validity of results from early stopped trials was threatened by small sample sizes. Incomplete reporting hampered a full analysis.

CONCLUSION

Few paediatric trials report on DMCs' roles, interim analysis or early stopping. Heterogeneous practices and apparent shortcomings jeopardize the validity of trial results. Easily accessible guidelines for the design, conduct and reporting of paediatric DMCs are needed.

Small sample approach, and statistical and epidemiological aspects

In this chapter, the design of pharmacokinetic studies and phase III trials in children is discussed. Classical approaches and relatively novel approaches, which may be more useful in the context of drug research in children, are discussed. The burden of repeated blood sampling in pediatric pharmacokinetic studies may be overcome by the population pharmacokinetics approach using nonlinear mixed effect modeling as the statistical solution to sparse data. Indications and contraindications for phase III trials are discussed: only when there is true "equipoise" in the medical scientific community, it is ethical to conduct a randomized clinical trial. The many reasons why a pediatric trial may fail are illustrated with examples. Inadequate sample sizes lead to inconclusive results. Twelve classical strategies to minimize sample sizes are discussed followed by an introduction to group sequential design, boundaries design, and adaptive design. The evidence that these designs reduce sample sized between 35 and 70% is reviewed. The advantages and disadvantages of the different approaches are highlighted to give the reader a broad idea of the design types that can be considered. Finally, working with DMCs during the conduct of trials is introduced. The evidence regarding DMC activities, interim analysis results, and early termination of pediatric trials is presented. So far reporting is incomplete and heterogeneous, and users of trial reports may be misled by the results. A proposal for a checklist for the reporting of DMC issues, interim analyses, and early stopping is presented.