Sample Size Calculation Research Articles

Patent Foramen Ovale Closure in Older Patients With Stroke: Patient Selection for Trial Feasibility.

Whether patent foramen ovale (PFO) closure benefits older patients with PFO and cryptogenic stroke is unknown because randomized controlled trials (RCTs) have predominantly enrolled patients younger than 60 years of age. Our objective was to estimate anticipated effects of PFO closure in older patients to predict the numbers needed to plan an RCT. Effectiveness estimates are derived from major observational studies (Risk of Paradoxical Embolism [RoPE] Study and Oxford Vascular Study, together referred to as the "RoPE-Ox" database) and all 6 major RCTs (Systematic, Collaborative, PFO Closure Evaluation [SCOPE] Consortium). To estimate stroke recurrence risk, observed outcomes were calculated for patients older than 60 years in the age-inclusive observational databases (n = 549). To estimate the reduction in the rate of recurrent stroke associated with PFO closure vs medical therapy based on the RoPE score and the presence of high-risk PFO features, a Cox proportional hazards regression model was developed on the RCT data in the SCOPE database (n = 3,740). These estimates were used to calculate sample sizes required for a future RCT. Five-year risk of stroke recurrence using Kaplan-Meier estimates was 13.7 (95% CI 10.5-17.9) overall, 14.9% (95% CI 10.2-21.6) in those with high-risk PFO features. Predicted relative reduction in the event rate with PFO closure was 12.9% overall, 48.8% in those with a high-risk PFO feature. Using these estimates, enrolling all older patients with cryptogenic stroke and PFO would require much larger samples than those used for prior PFO closure trials, but selectively enrolling patients with high-risk PFO features would require totals of 630 patients for 90% power and 471 patients for 80% power, with an average of 5 years of follow-up. Based on our projections, anticipated effect sizes in older patients with high-risk features make a trial in these subjects feasible. With lengthening life expectancy in almost all regions of the world, the utility of PFO closure in older adults is increasingly important to explore.

TEACHERS’ CONFLICT-INDUCING ATTITUDES AND THEIR REPERCUSSIONS ON STUDENTS’ PSYCHOLOGICAL HEALTH

This purpose of the study was to determine the influence of teachers conflict-inducing attitudes on the students psychological health. A total of 110 public elementary school teachers teaching in Tarragona District, Davao Oriental Division were identified through Tabachnick and Fidell (2007) calculation of sample size. The study utilized a descriptive-correlation design. Mean, Pearson r, and regression analysis were used as statistical tools of the study. Results revealed on the extent of teachers conflict inducing attitudes in terms of Teacher Incivility were sometimes evident, in terms of Teacher Discrimination was sometimes evident, in terms of University Resources was oftentimes evident. On the Students Psychological Health was always evident. Clearly, the findings inferred a strong significant relationship between teachers conflict-inducing attitudes and students psychological health. Based on the result of the analysis, the teachers conflict inducing attitudes domains namely: teacher incivility, teacher discrimination, and university resources significantly influences students psychological health by registering a p-value of less than.000 in the level of significance. Further, the result indicates that for every unit increase in the three domains of teachers conflict inducing attitudes predictors, the students psychological health will increase by 3.894 holding other factors constant. Conflict inducing attitudes significantly influenced students psychological health. Hence, this study recommends teachers should be encouraged professional development programs that target specific conflict-inducing attitudes, leading to personal growth and improved professional practice. Teachers should engage in training and workshops that help them develop stronger interpersonal skills and conflict resolution strategies. KEYWORDS: Teachers conflict inducing attitudes, psychological health, teacher incivility, teacher discrimination, university resources

Comparison of plasma and neuroimaging biomarkers to predict cognitive decline in non-demented memory clinic patients.

Plasma biomarkers of Alzheimer's disease (AD) pathology, neurodegeneration, and neuroinflammation are ideally suited for secondary prevention programs in self-sufficient persons at-risk of dementia. Plasma biomarkers have been shown to be highly correlated with traditional imaging biomarkers. However, their comparative predictive value versus traditional AD biomarkers is still unclear in cognitively unimpaired (CU) subjects and with mild cognitive impairment (MCI). Plasma (Aβ42/40, p-tau181, p-tau231, NfL, and GFAP) and neuroimaging (hippocampal volume, centiloid of amyloid-PET, and tau-SUVR of tau-PET) biomarkers were assessed at baseline in 218 non-demented subjects (CU = 140; MCI = 78) from the Geneva Memory Center. Global cognition (MMSE) was evaluated at baseline and at follow-ups up to 5.7 years. We used linear mixed-effects models and Cox proportional-hazards regression to assess the association between biomarkers and cognitive decline. Lastly, sample size calculations using the linear mixed-effects models were performed on subjects positive for amyloid-PET combined with tau-PET and plasma biomarker positivity. Cognitive decline was significantly predicted in MCI by baseline plasma NfL (β=-0.55), GFAP (β=-0.36), hippocampal volume (β = 0.44), centiloid (β=-0.38), and tau-SUVR (β=-0.66) (all p < 0.05). Subgroup analysis with amyloid-positive MCI participants also showed that only NfL and GFAP were the only significant predictors of cognitive decline among plasma biomarkers. Overall, NfL and tau-SUVR showed the highest prognostic values (hazard ratios of 7.3 and 5.9). Lastly, we demonstrated that adding NfL to the inclusion criteria could reduce the sample sizes of future AD clinical trials by up to one-fourth in subjects with amyloid-PET positivity or by half in subjects with amyloid-PET and tau-PET positivity. Plasma NfL and GFAP predict cognitive decline in a similar manner to traditional imaging techniques in amyloid-positive MCI patients. Hence, even though they are non-specific biomarkers of AD, both can be implemented in memory clinic workups as important prognostic biomarkers. Likewise, future clinical trials might employ plasma biomarkers as additional inclusion criteria to stratify patients at higher risk of cognitive decline to reduce sample sizes and enhance effectiveness.

Pre-ANDA strategy and human factors activities to de-risk pharmaceutical companies ANDA submission of drug-device combination products: case study of a formative comparative use human factors study.

This article presents a strategy that a Drug Delivery Device Developer (DDDD) has adopted to support Abbreviated New Drug Application (ANDA) submissions of drug-device combination products. As per the related FDA guidance, a threshold analysis should be compiled. If 'other differences' between the Reference Listed Drug (RLD) and the generic drug devices are identified, a Comparative Use Human Factors (CUHF) study may be requested. The DDDD performed task analysis and physical comparison to assess the pen injector design differences. Then, a formative CUHF study with 25 participants simulating injections using both RLD and the generic pen injectors was conducted. After each participant completed four simulated injections, similar type and rates of use error between the RLD (0.70) and generic (0.68) pen injectors were observed. DDDDs can support pharmaceutical companies in the ANDA submission strategy of their drug-device combination product by initiating comparative task analysis and physical comparison of the device as inputs for the threshold analysis. If 'other differences' are identified, a formative CUHF study can be performed. As shown in our case study, this approach can be leveraged to support the sample size calculation and non-inferiority margin determination for a CUHF study with the final combination product.

Has Coca-Cola treatment become the first-line therapy for gastric bezoars, both in general and specifically for western countries?

Phytobezoars is a rare disease and less common in Western countries. The stomach is the primary site for these formations, and endoscopic treatment involving fragmentation and extraction has traditionally been the most effective approach. However, medical treatments using enzymatic and chemical agents, such as cellulase and Coca-Cola, aimed at dissolving the bezoars, have also been utilized, showing varying degrees of resolution success. Notably, the oral dissolution treatment with Coca-Cola has emerged as a promising, simpler, and more cost-effective method. The study by Liu et al represents an important step in clinical research on this topic, despite some limitations that need addressing for a more comprehensive understanding of its findings. Key considerations for future research include sample size calculation, endoscopic procedure details, outpatient vs. inpatient treatment, and detailed cost calculations. The study's exclusions, such as patients with upper gastric surgery, phytobezoars older than 14 d, and cases of gastroparesis, limit its applicability to broader populations, especially in Western countries. Given the promising outcomes of the Coca-Cola treatment, it's advocated as a first-line therapy for phytobezoars. Nonetheless, further research is essential to overcome these limitations. However special situations such as perforation or small bowel obstruction will require surgical treatment.

Multilevel Intervention Stepped Wedge Designs (MLI-SWDs).

Multilevel interventions (MLIs) hold promise for reducing health inequities by intervening at multiple types of social determinants of health consistent with the socioecological model of health. In spite of their potential, methodological challenges related to study design compounded by a lack of tools for sample size calculation inhibit their development. We help address this gap by proposing the Multilevel Intervention Stepped Wedge Design (MLI-SWD), a hybrid experimental design which combines cluster-level (CL) randomization using a Stepped Wedge design (SWD) with independent individual-level (IL) randomization. The MLI-SWD is suitable for MLIs where the IL intervention has a low risk of interference between individuals in the same cluster, and it enables estimation of the component IL and CL treatment effects, their interaction, and the combined intervention effect. The MLI-SWD accommodates cross-sectional and cohort designs as well as both incomplete (clusters are not observed in every study period) and complete observation patterns. We adapt recent work using generalized estimating equations for SWD sample size calculation to the multilevel setting and provide an R package for power and sample size calculation. Furthermore, motivated by our experiences with the ongoing NC Works 4 Health study, we consider how to apply the MLI-SWD when individuals join clusters over the course of the study. This situation arises when unemployment MLIs include IL interventions that are delivered while the individual is unemployed. This extension requires carefully considering whether the study interventions will satisfy additional causal assumptions but could permit randomization in new settings.

Sample size calculation for comparing two screening tests when the gold standard is missing at random.

Sample size formulas have been proposed for comparing two sensitivities (specificities) in the presence of verification bias under a paired design. However, the existing sample size formulas involve lengthy calculations of derivatives and are too complicated to implement. In this paper, we propose alternative sample size formulas for each of three existing tests, two Wald tests and one weighted McNemar's test. The proposed sample size formulas are more intuitive and simpler to implement than their existing counterparts. Furthermore, by comparing the sample sizes calculated based on the three tests, we can show that the three tests have similar sample sizes even though the weighted McNemar's test only use the data from discordant pairs whereas the two Wald tests also use the additional data from accordant pairs.

Implementation and dissemination of physical activity-related health competence in vocational nursing training: study protocol for a cluster-randomized controlled intervention trial

BackgroundAlthough the nursing sector gains growing importance in an aging society, students representing the future workforce often show insufficient health. Acknowledging the health-enhancing effects of adequate physical activity, the educational system in Bavaria, Germany, has recently integrated the promotion of physical activity-related health competence (PAHCO) into the nursing curriculum. However, it cannot be assumed that PAHCO has sufficiently permeated the educational practices and routines of the nursing schools. Therefore, the goal of the present study is to examine and compare the effectiveness as well as implementation of different intervention approaches to address PAHCO in the Bavarian nursing school system.MethodsWe randomly assign 16 nursing schools (cluster-based) to four study arms (bottom-up, top-down led by teachers, top down led by external physical activity experts, control group). Schools in intervention group 1 (IG-1) develop multicomponent inventions to target PAHCO via cooperative planning (preparation, planning, and implementation phase). Intervention groups 2 and 3 (IG-2, IG-3) receive both an expert-based intervention (developed through intervention mapping) via trained mediators to address PAHCO. External physical activity experts deliver the structured PAHCO intervention in IG-2, while teachers from the nursing schools themselves conduct the PAHCO intervention in IG-3. In line with a hybrid effectiveness implementation trial, we apply questionnaire-based pre-post measurements across all conditions (sample size calculation: nfinal = 636) to examine the effectiveness of the intervention approaches and, simultaneously, draw on questionnaires, interview, and protocol data to examine their implementation. We analyze quantitative effectiveness data via linear models (times-group interaction), and implementation data using descriptive distributions and content analyses.ConclusionThe study enables evidence-based decisions about the suitability of three intervention approaches to promote competencies for healthy, physically active lifestyles among nursing students. The findings inform dissemination activities to effectively reach all 185 schools of the Bavarian nursing system.Trial registrationClinical trials NCT05817396. Registered on April 18, 2023.

Study protocol of a prospective, interventional non-randomised trial investigating the impact of asthma education on specific disease understanding, health literacy and therapy outcome in childhood

IntroductionChildhood asthma is a highly prevalent chronic disease. A failure to implement patient education programmes may result in increased morbidity, despite the availability of distinct diagnostic and therapeutic approaches. Patients...

Health Risk Associated with Conventional Skin Lighteners and Female Civil Servants’ Comprehension of Skin Lightening Ingredient Information in Anambra State

Skin-lightening products have been in use for many years to lighten skin colour. However, these products contain chemicals that can alter the skin's chemical structure and inhibit the production of melanin. Therefore, users of these products need to understand the ingredients and the potential health risks associated with their use. A study was conducted to assess the health risks associated with conventional skin-lightening products and to determine how well female civil servants understood the ingredient information on the product packaging. The study aimed to determine how many women read the ingredient information on these products, how many understood the information, and how many were aware of the health risks associated with their use. The study was conducted as a survey of 348 civil servants from 21 Ministries in Anambra State using an online sample size calculator. The study was anchored on the Individual Difference theory and selective perception media effect. The survey found that a significant number of female civil servants in Anambra state do not read the ingredient information on skin-lightening products. It was also discovered that the majority of female civil servants in Anambra State do not comprehend the product ingredient information because of its technical nature. Despite this, the study found that most women were aware of the health risks associated with the use of these products. The study concluded that female civil servants in Anambra State were aware of the ingredient information composition on skin-lightening products, but did not read it, making it difficult for them to understand and interpret the information. However, most of these women were still aware of the health risks associated with the use of skin-lightening products but still used them because of the benefits they claimed to have experienced. The study recommended that manufacturers and brand designers should simplify the technical language used to describe the product ingredients to make it easier for users to understand. Additionally, regulatory agencies like NAFDAC and SON should ensure that manufacturers produce skin products that do not contain harmful chemicals like hydroquinone, corticosteroids, and mercury. If these chemicals are used, users should be informed of the negative side effects.

Change-readiness instrument for library managers: development and analysis of a scale

PurposeThis study focuses on developing a scale that encompasses aspects of readiness to change by library management in dealing with the next normal scenario in libraries. It investigates measuring change readiness in terms of library service operations, workflows, administration, programs and spaces, which can give an overview of a library institution's preparedness to meet new roles and expectations.Design/methodology/approachThe descriptive quantitative research was employed using a two-phase approach. It attempts to design an instrument referred to as change-readiness instrument for library managers (CRILM), which was derived from an original self-developed questionnaire consisting of a 20-item readiness-for-change attributes. Validity and reliability of CRILM were tested using Exploratory Factor Analysis and Cronbach’s Alpha. Sample size calculation was employed to determine the required number of subjects to participate in the study. Library managers who are head librarians from different types of libraries were the target samples. Content validation of the items was conducted for suitability and context.FindingsCRILM was tested both valid and reliable. The initial results yielded from the respondent sample indicated that CRILM is deemed suitable for measuring change-readiness among library managers and libraries. The factor-analyzed items were grouped into three subscales based on their characteristics, namely, flexibility in work and services, learning support readiness and adaptive to changing service environments.Research limitations/implicationsCRILM covered the major domains and constructs of change readiness in the context of a library setting. However, the scale should be subjected to further testing and use by a wider target group to strengthen its usability and confidence level. Item analysis was not employed.Practical implicationsThe results of the study offer help to library managers in assessing the readiness of their organizations to effectively manage change and be future-ready.Originality/valueThis study attempts to bridge the gap in readiness-for-change instruments by introducing a scale in the library service environment as a potential contribution in the practice of library management.

Clinical Profile and In-hospital Outcome of Acute Household Substances Poisoning in a Tertiary Care Hospital

Background: Poisoning is an acute medical emergency. Among the thousands of harmless products available for household, very few are hazardous. Still, self-poisoning with these substances is one of the commonest mode of poisoning. This study was carried out to get information related to clinical profile and inhospital outcome of household substances poisoning in a particular area of Bangladesh. Methods: This cross-sectional type of descriptive study was carried out in the department of Medicine, Sylhet M.A.G. Osmani Medical College Hospital, Sylhet, Bangladesh during the period of June 2022 to November 2022.Purposive convenient sampling was applied to recruit sample from study population. Calculated sample size was 64. Detailed history including nature of poisoning (unintentional/ intentional), route of poisoning, type of poison, symptoms and signs with relevant laboratory findings were documented in a structured data collection sheet through interview from the patient or their guardians after obtaining informed written consent. In-hospital outcome in terms of survival (discharged, discharge without advice/absconded) and mortality were recorded.Results:Among 64 participants majority 65.63% (n=42) were female and most 56.25% (n=36) were of 18-20 years age group.Regarding educational status 96.87 %(n=62) participants were educated. All of the poisoning were intentional and by oral route. Harpic was the most common agents 59.38% (n=38) used by the victims.Vomiting was the most common 81.25% (n=52) symptomand oral ulcer was the commonest 40.63% (n=26) sign. No significant abnormality of vital signs and laboratory investigations were found. Majority of the respondents 43.75 % (n=28) stayed 2 days in hospital for treatment purpose. Total 85.94% (n=55) respondents were discharged with advice and 14.06% (n=9) respondents left hospital without medical advice. No death was documented in this study. Conclusion: Young teenaged female patients were the majority of victims in our study reflecting the degree of powerlessness and hopelessness of young, educated people with unemployment and difficulties in coping with life stressors. Bangladesh J Medicine 2024; 35: 70-75

A Predictive Noninvasive Single-Nucleotide Variation-Based Biomarker Signature for Resectable Pancreatic Cancer: Protocol for a Prospective Validation Study.

Single-nucleotide variations (SNVs; formerly SNPs) are inherited genetic variants that can be easily determined in routine clinical practice using a simple blood or saliva test. SNVs have potential to serve as noninvasive biomarkers for predicting cancer-specific patient outcomes after resection of pancreatic ductal adenocarcinoma (PDAC). Two recent analyses led to the identification and validation of three SNVs in the CD44 and CHI3L2 genes (rs187115, rs353630, and rs684559), which can be used as predictive biomarkers to help select patients most likely to benefit from pancreatic resection. These variants were associated with an over 2-fold increased risk for tumor-related death in three independent PDAC study cohorts from Europe and the United States, including The Cancer Genome Atlas cohorts (reaching a P value of 1×10-8). However, these analyses were limited by the inherent biases of a retrospective study design, such as selection and publication biases, thereby limiting the clinical use of these promising biomarkers in guiding PDAC therapy. To overcome the limitations of previous retrospectively designed studies and translate the findings into clinical practice, we aim to validate the association of the identified SNVs with survival in a controlled setting using a prospective cohort of patients with PDAC following pancreatic resection. All patients with PDAC who will undergo pancreatic resection at three participating hospitals in Switzerland and fulfill the inclusion criteria will be included in the study consecutively. The SNV genotypes will be determined using standard genotyping techniques from patient blood samples. For each genotyped locus, log-rank and Cox multivariate regression tests will be performed, accounting for the relevant covariates American Joint Committee on Cancer stage and resection status. Clinical follow-up data will be collected for at least 3 years. Sample size calculation resulted in a required sample of 150 patients to sufficiently power the analysis. The follow-up data collection started in August 2019 and the estimated end of data collection will be in May 2027. The study is still recruiting participants and 142 patients have been recruited as of November 2023. The DNA extraction and genotyping of the SNVs will be performed after inclusion of the last patient. Since no SNV genotypes have been determined, no data analysis has been performed to date. The results are expected to be published in 2027. This is the first prospective study of the CD44 and CHI3L2 SNV-based biomarker signature in PDAC. A prospective validation of this signature would enable its clinical use as a noninvasive predictive biomarker of survival after pancreatic resection that is readily available at the time of diagnosis and can assist in guiding PDAC therapy. The results of this study may help to individualize treatment decisions and potentially improve patient outcomes. DERR1-10.2196/54042.

Citizens’ Perception on Effects of Kidnapping on Security in Edo South Senatorial District

The cases of kidnapping in Nigeria and in Edo State in particular are rising, and taking dangerous dimensions. What exists in the literature is an ample of research reports on the causes and socioeconomic implications of kidnapping. The general objective of this study is to explore citizens’ perception of the effects of the rising incidence of kidnapping on the security situations in Edo South Senatorial District of Edo State. The exploratory research design operated with the cross sectional research design was adopted for this study. The calculated sample size for this study was placed at approximately 816. For the collection of qualitative data, the purposive sampling techniques were used to select two interviewees from each of the local government areas. Hence, there were 14 interviewees for the collection of qualitative data that complemented the quantitative data. The majority of respondents (54.7%) believe that the death of victims during kidnappings is avoidable or preventable. There was statistically significant difference in the perception of the level of panic due to kidnapping in Edo South according to the age groups. There is statistically significant association between educational qualification and the tendency to get the Police involved in cases of kidnapping. There was statistically significant difference in perceived police effectiveness in the fight against kidnapping in Edo South according the respondents’ nature of employment. In conclusion, there is a significant number of people who are concerned about kidnapping in their area, with most of affirming a high level of panic due to kidnapping. Kidnapping has a negative impact on society and is a source of fear and concern for many people. The lack of proper security measures adds to the problem, and people are left to take precautions to avoid being kidnapped. The citizens are adjusting to the panic caused by kidnapping by taking practical measures to ensure their safety and seeking solace through spiritual practices. It is recommended that the police should take proactive measures to prevent kidnappings, have the necessary resources and training to handle kidnapping cases, and work with other security agencies and organizations to provide support and services to victims after their release.

An interventional cross-sectional study of electrolyte levels in newborns with hyperbilirubinemia before and after phototherapy in a tertiary care hospital in central India

Introduction This study protocol outlines a comprehensive investigation into the impact of phototherapy on electrolyte levels in newborns with hyperbilirubinemia. With a focus on neonates admitted to the Neonatal Intensive Care Unit (NICU) at Jawaharlal Nehru Medical College and AVBR Hospital, Sawangi, Wardha, Central India, the research aims to contribute valuable insights into the physiological changes associated with this common neonatal condition. The study’s introduction highlights the rationale, significance, and gaps in current knowledge, emphasising the need for a detailed exploration of electrolyte dynamics before and after phototherapy. Method The methodology involves a descriptive, interventional cross-sectional design with a calculated sample size of 264 neonates. Standardised protocols for data collection, including serum electrolyte analysis and urine-specific gravity assessment, will be employed. Inclusion and exclusion criteria are clearly defined to ensure a homogenous study population. Statistical analyses, utilising R Studio 4.3.1 will encompass descriptive statistics, comparative analysis, correlation analysis, and multivariate analysis to explore the nuanced relationships between variables. Rigorous ethical considerations and transparency in reporting will guide the data collection process. Expected Result Anticipated outcomes include a nuanced understanding of changes in serum electrolyte levels following phototherapy and the correlation of these changes with the treatment duration. The study is poised to shed light on the impact of gestational age and birth weight on electrolyte responses. Through rigorous statistical analysis, the research aims to provide evidence-based insights that can inform neonatal care protocols. The anticipated findings hold the potential to influence clinical practices, enhancing the quality of care provided to newborns with hyperbilirubinemia undergoing phototherapy.

A Comparison Between Skeletal Class II and Class III Malocclusion Patients in Terms of the Masticatory Muscles' Activity: A Cross-Sectional Study.

Background This study aimed to determine if individuals with skeletal Class II and skeletal Class III malocclusions had different levels of masticatory muscle activity. Materials and methods This cross-sectional study, conducted at the University of Damascus, investigated the myoelectric activity of perioral muscles in patients with Class II and III malocclusions. The sample size of 60 patients was determined according to a prior sample size calculation. Patients were selected based on specific inclusion and exclusion criteria and divided into Class II and III groups. Electromyography was used to monitor the activity of various muscles, including the temporalis, masseter, orbicularis oris, buccinator, mentalis, and digastric muscles. Results The study found similar muscle activity within the same group in the temporalis, masseter, buccinator, digastric, and orbicularis oris muscles. No significant differences were observed between the Class II and III groups for several oral and perioral muscles (P > 0.05). However, the mean activity of the digastric muscle was significantly greater in the Class II group (P < 0.05), whereas the mean activity of the mentalis muscle was smaller in the Class II group (P < 0.05). Conclusions Perioral muscles influence facial complex development and jaw relationship, affecting orthodontic treatment. Digastric muscle activity is greater in Class II patients, while mental muscle activity is smaller in Class III patients. Further studies are needed for older age groups and other skeletal malocclusion types.

Improved Test Procedure and Sample Size Calculation for Assessing Similarity in Two-Group Comparative Studies with Heterogeneous Variances

AbstractThe two one-sided tests (TOST) method for mean equivalence or average equivalence has been extended to assessing similarity or switchability for individual equivalence in clinical trials. Tolerance interval procedures are available to establish similarity with respect to the proportion of the response differences covered by a prespecified threshold range. However, the extended TOST procedures based on tolerance intervals are potentially susceptible to the control of Type I errors. This article aims to present an exact approach with the specified Type I error probability for appraising similarity between two treatments in comparative studies with heterogeneous variances. Analytic examination and numerical comparison are conducted to clarify the utility of the suggested similarity test and the drawback of the current TOST procedures. To enhance the usefulness of the described exact method, the related power and sample size issues are also considered. Computer algorithms are provided to implement the proposed test procedure, power calculation, and sample size determination in similarity studies.

Prevalence of Noncommunicable Disease (NCDs) risk factors in Tamil Nadu: Tamil Nadu STEPS Survey (TN STEPS), 2020.

Noncommunicable diseases (NCDs) account for nearly 75% of all deaths in Tamil Nadu. The government of Tamil Nadu has initiated several strategies to control NCDs under the Tamil Nadu Health Systems Reform Program (TNHSRP). We aimed to estimate the prevalence of NCD risk factors and determine the predictors of diabetes and hypertension, which will be helpful for planning and serve as a baseline for evaluating the impact of interventions. A state-wide representative cross-sectional study was conducted among 18-69-year-old adults in Tamil Nadu in 2020. The study used a multi-stage sampling method to select the calculated sample size of 5780. We adapted the study tools based on WHO's STEPS surveillance methodology. We collected information about sociodemographic factors, NCD risk factors and measured blood pressure and fasting capillary blood glucose. The predictors of diabetes and hypertension were calculated using generalised linear models with 95% confidence intervals (95% CI). Due to the COVID-19 pandemic lockdown, we could cover 68% (n = 3800) of the intended sample size. Among the eligible individuals surveyed (n = 4128), we had a response rate of 92%. The mean age of the study participants was 42.8 years, and 51% were women. Current tobacco use was prevalent in 40% (95% CI: 33.7-40.0) of men and 7.9% (95% CI: 6.4-9.8) of women. Current consumption of alcohol was prevalent among 39.1% (95% CI: 36.4-42.0) of men. Nearly 28.5% (95% CI: 26.7-30.4) of the study participants were overweight, and 11.4% (95% CI: 10.1-12.7) were obese. The prevalence of hypertension was 33.9% (95% CI: 32.0-35.8), and that of diabetes was 17.6% (95% CI: 16.1-19.2). Older age, men, and obesity were independently associated with diabetes and hypertension. The burden of NCD risk factors like tobacco use, and alcohol use were high among men in the state of Tamil Nadu. The prevalence of other risk factors like physical inactivity, raised blood pressure and raised blood glucose were also high in the state. The state should further emphasise measures that reduce the burden of NCD risk factors. Policy-based and health system-based interventions to control NCDs must be a high priority for the state.

Exploring Sample Size Determination in Educational Research: A Comprehensive Review

Background By conducting an in-depth study of the publications, a review was conducted with the goal of evaluating the sample size in educational research. The sample size, represented by the letter “n,” is a key factor in this research because it specifies the number of participants who represent the target population. Although various studies have been published in the literature defining the processes for calculating sample sizes, there is still much uncertainty. It is vital to understand that there is no single all-encompassing method for determining sample sizes for different study designs. Instead, different study designs call for different approaches to determine sample numbers. Methods Information was retrieved from the databases in accordance with updated PRISMA recommendations. The keywords used for the retrieval of the relevant articles from two databases (Google Scholar and PubMed). The articles were selected by thorough scrutiny and application of inclusion and exclusion criteria. Results Seven articles were selected and the comparison was made among the studies in the relation to methods, objective, and outcome from the enrolled studies. Conclusions The evaluation of the seven studies as a whole concluded that the sample size for testing any novel approach essentially required 24.24 participants in each group. The median sample size for the simulation-based educational research was 30. Further research is required to determine the proper sample size based on a single universal formula for all types of designs.

Adaptive two-stage seamless sequential design for clinical trials

ABSTRACT We propose an adaptive sequential testing procedure for the selection and testing of multiple treatment options, such as dose/regimen, different drugs, sub-populations, endpoints, or a mixture of them in a seamlessly combined phase II/III trial. The selection is to be made at the end of phase 2 stage. Unlike in many of the published literature, the selection rule is not required to be to “select the best”, and does not need to be pre-specified, which provides flexibility and allows the trial investigators to use any efficacy and safety information/criteria, or surrogate or intermediate endpoint to make the selection. Sample size and power calculations are provided. The calculations have been confirmed to be accurate by simulations. Interim analysis can be performed after the selection, sample size can be modified if the observed efficacy deviates from the assumed. Inference after the trial, including p-value, median unbiased point estimate and confidence intervals, are provided. By applying a dominance theorem, the procedure can be applied to normal, binary, Poisson, negative binomial distributed endpoints and time-to-event endpoints, and a mixture of these distributions (in trials involving endpoint selection).