SM Journal of Biometrics & Biostatistics

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Forming the Differential Equations from Simple Polynomial Regression Models

It is presented a method useful to form ordinary differential equations from nonlinear regression models of the type , a power series allowing to directly retrieving the differential model from raw data after fitting, to be differential equation itself. compared with the differential model expected for the biological system which is studied. In particular for any possible value of n, the highest power at which the independent variable is raised, the paper gives the method to get the differential equation having the polynomial as solution. The use of power series allows some practical advantages when dealing with differential equations, and one of these - in some

Michele Nichelatti*


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Assessing Non-Inferiority Hypothesis in Two-Arm Trials with Log-Normal Data

In health related studies, non-inferiority tests are used to demonstrate that a new treatment is not worse than a currently existing treatment by more than a pre-specified margin. In this paper we have proposed a Bayesian approach and compared it with two other methods available in the literature. We discuss three approaches; a Z-score approach, a generalized p-value approach and a Bayesian approach, to test the non-inferiority hypotheses in two-arm trials for ratio of log-normal means. The log-normal distribution is widely used to describe the positive random variables with positive skewness which is appealing for data arising from studies with small sample sizes. We demonstrate the approaches using data arising from an experimental aging study on cognitive penetrability of posture control. We also examine the suitability of three methods under various sample sizes via simulations. The results from the simulation studies indicate that the generalized p-value and the Bayesian approach reach an agreement approximately and the degree of the agreement increases when the sample sizes increase. However, the Z-score approach can produce unsatisfactory results even under large sample sizes.

Lahiru Wickramasinghe1 and Saman Muthukumarana1*


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The Assessment of Concerns, Opinions and Perceptions of Biometric Technologists to Find the Significant Metrics for Deployment of Biometrics in E-Banking

The research work was conducted with the objective to find the significant metrics for biometrics deployment in e-banking through an assessment of the concerns, opinions and perceptions of biometric technologists regarding the implementation of biometrics in e-banking. This paper is pursued by collecting information through survey of technologists working with biometrics; the technologists are chosen using snowball sampling. Then the results of the surveys are analyzed to find the significant metrics for the deployment of biometrics technology in e-banking. The study suggests that the overall significant metrics for the deployment of Biometric technology in E-Banking with the biometric technologists perspective are Performance, Circumvention Resistance, Collectability, Size and Comparability, Minimum Operational Limitations, Intrusion Level and Portability.

Dr. Munish Sabharwal1*


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Progressive Alpha-Exhaustive Multiple Testing Procedure with Independent Test Statistics

A multiple testing procedure can be a single-step data-independent procedure, such as Bonferroni’s method, or a data-dependent stepwise procedure such as Hochberg’s step-up method and Hommel’s method. It can be an α-exhaustive, where the maximum type-I error rate under all configurations of null hypotheses equals α, or α-conservative, where the type-I error rate falls below the nominal level. We develop a simple one-step a-exhaustive procedure that can improve power 2%-5% over Hochberg’s and Hommel’s methods in common situations when the test statistics are mutually independent. The method can also be generalized to correlated test statistics. In our method we construct the stopping rules using the product of marginal p-values and control the upper bounds of the kth order terms so that α is exhausted for any configuration of k null hypotheses. Such upper bounds are determined progressively from k = 1 towards k = K, the number of null hypotheses in the problem. The method can be used in different multiple testing problems, including adaptive clinical trial designs.

Mark Chang1,2*, Xuan Deng1, John Balser2 and Robin Bliss2


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Mediation Analysis of Co-occurring Conditions for Complex Longitudinal Clinical Data

Background: Symptoms or test results may be common to two or more co-occurring conditions. This problem of symptom overlap makes it challenging for clinicians to determine a focus for treatment in a patient given changes in the severity of either condition.

Methods: Structural equation modeling methods can be used to disentangle some of the complexities of disease symptom etiology, given co-occurring conditions, and support treatment decision making. These techniques provide the flexibility to deal with specific challenges present in data as extracted from Electronic Health Records (EHR) (i.e. individually varying follow up times, irregular follow up, missingness, systematic error in patient reported outcomes, lack of clear temporal precedence between measures). Specifically, a proposed latent growth modeling approach accounting for differential item functioning along with the Monte Carlo simulation method for assessment of mediation can be used to investigate how one condition leads to a co-occurring condition, adjusted for the overlapping symptoms of both conditions.

Results: This paper uses an example investigating how Multiple Sclerosis (MS) leads to depression in patients in which depressive symptoms overlap with other symptoms of MS, such as fatigue, cognitive impairment and physical impairment to illustrate the methods. It was demonstrated that not adjusting for this overlap can lead to different results.

Conclusions: Developing methods for mediation analysis of co-occurring conditions for more complex longitudinal clinical data as recorded at a typical patient visit can help clinicians make improved use of data bases such as EHR to support clinical decision making in real time.

Douglas D. Gunzler1*, Nathan Morris2, Adam Perzynski1, Deborah Miller3, Steven Lewis1 and Robert A. Bermel3


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Review on the Evaluation of Impact of Language and Culture on the Validity of Pain Quality Measures in Nepal: Encapsulation

Background: A study with aim to evaluate the impact of language and culture on the validity of pain quality measures by comparing the words spoken by individuals with chronic pain indicated that direct translations of measures that are developed using samples of patients from one country or culture are not necessarily content valid for use in other countries or cultures; some adaptations may be required in order for such measures to be most useful in new language and culture.

Objective: To re-evaluate the article Journal of Pain Research 2016:9 1057–1066, and reflect on the implications of its recommendations.

Methods: Content analysis of article published in Journal of Pain Research 2016:9 1057–1066., Critical review of the specified article was performed, its components, overall integrity assessed, relevant information was obtained from profiles, references, citations, and web. Current developments and changes in state of science and art are collected. Finally the general, philosophical, theoretical, methodological, and analytic output are presented.

Result: There was no complete theory, concepts, definition of terms. Topics were not covered, authors were uncertain on their sample size, sampling and its reliability. Content validity itself not defined determined, tested and presented. Interdependence of individuals, their previous and current works prevailed. Result was inconclusive. Finally concurrent changes in definition, change in tools, were not accounted for. The membership degree of authors is deep rooted.

Conclusion: The article provided unwarranted conclusion and recommendation.

Recommendation: Refinement, self- rectification and transformation.

Sahilu Assegid*


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Statistical Analysis and Inter Comparison of Solar UVB and Global Radiation for Athalassa and Larnaca, Cyprus

A statistical analysis and inter-comparison of the broadband ultraviolet-B (UVB) radiation at two sites in Cyprus representing two different climate regimes of the island (Athalassa-inland plain vs Larnaca-coastal location) covering the period January 2013-December 2015 is presented. Mean annual and mean monthly daily totals of the UVB irradiation and their frequency distribution at both sites are computed and discussed. Daily maximum of hourly average irradiance values occur in July, 2.09 W m-2, and minimum, 0.47 W m-2, in December at solar noon at Athalassa. The respective values at Larnaca are slightly higher (2.48 W m-2 and 0.67 W m-2, respectively). UVB daily values follow the pattern of the solar altitude angle; the total accumulated UVB irradiation along a mean year reaches 10.27 MJ m-2 at Athalassa and 13.49 MJ m-2; maximum stability of UVB takes place at midday hours during the summer. Large fluctuations of the daily UVB irradiation are observed in the spring months and November, which are mainly due to unstable meteorological conditions during the transition from cold to warm weather and vice versa. During summer the daily UVB radiation exceeds the value of 70 kJ m-2 at Larnaca and 55 kJ m-2 at Athalassa, while during the winter season the lowest is about 5 kJ m-2 at both stations. The UVB potential and extraterrestrial irradiation has also been calculated in order to estimate the attenuation of UVB radiation through the atmosphere. During summer the UVB transmittance is higher than in winter with a maximum value of 9% in July and a minimum of about 4% in December. Statistical relationships between UVB and other radiation components (UVA and global radiation) were established.

Pashiardis S1, Kalogirou SA1* and Pelengaris A2


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A Structured Review of Relation between Full Moon and Different Aspects of Human Health

Full moon is the lunar phase that occurs when the moon is illuminated completely as seen from the earth Across the centuries many a person has attered the phrase, ‘there must be a full moon out there’ in an attempt to explain weird happening at night. Even today many people think the mystical power of full moon induce erratic behavior, psychiatric, hospital admission, suicide, homicide, sleep pattern, birth of baby, emergency room call, traffic accident and all manners of strange events. The main objective of this review is to find out the effect of full moon on different aspect of human health. The study was undertaken Kumudini Women’s Medical College, Bangladesh during the period between June 2016 to May 2017. Here we summarized the literature of 33 trials collected from secondary sources like Pub Med, Goggle Scholar and other different articles through online searching. The coverage of the study was effect of full moon on cardiovascular system, endocrine system, on behavior, on reproductive system, on behavior system of human being. The ultimate result of this review in maximum cases no significant changes observed in human health. In spite of these findings there is further scope for elaborate study on this aspect.

Anannya Roy1, Tonmoy Biswas2 and Ajit Kumar Roy3*


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Improved Ratio cum Product Estimators for Finite Population Mean with Known Quartiles and Their Functions

In sample surveys auxiliary information is quite often available from previous experience and using the auxiliary information several estimators are introduced like Ratio estimator modified ratio and product estimators for the estimation of population mean. This manuscript deals with the improvements on ratio cum product estimators for the estimation of population mean of the study variable by using the known values of quartiles of the auxiliary variable and their functions. The bias and mean squared error of proposed estimators are obtained. An empirical condition is developed to assess the performance of proposed estimators over the existing estimators. A numerical study is carried out to assess the efficiency of proposed estimators over the existing estimators with the help of some known natural populations. Based on the simulation study and numerical studies, the proposed estimators are less biased (almost unbiased) and it performs better than the existing estimators.

Jambulingam Subramani and Master Ajith S*


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Characteristics of Photosynthetic Active Radiation (PAR) Through Statistical Analysis at Larnaca, Cyprus

Measurements of Photosynthetically Active Radiation (PAR) and global solar radiation at Larnaca (a coastal site in Cyprus) during the period 3013-2015 were used to investigate the seasonal characteristics of PAR and PAR/G ratio (PAR fraction or fFEC). PAR showed seasonal features with higher values in summer and lower values in winter. The annual mean values of PPFD and fFEC being 40.3 mol m-2 d-1 and 2.03 mol M J-1, respectively. Monthly average daily PAR increased from 19.1 mol m-2 d-1 (in December) to 59.6 mol m-2 d-1 (in June).The monthly daily average of fFEC remained almost constant throughout the year at Larnaca. The spatial variability of PAR was also investigated using measurements from other four sites with different climate characteristics. The annual mean daily PAR value ranged between 31.7 to 40.0mol m-2 d-1. The highest values are recorded in the coastal stations (Larnaca and Paralimni). The annual average value of fFEC at the five observation sites ranged from 1.82 mol MJ-1 to 2.03 mol MJ-1, in accordance to what is observed in most parts of the world. The highest appeared in the coastal sites of Larnaca and Paralimni due to the presence of high water vapour atmospheric concentrations. Elevation plays a significant role on the values of the above variables. As a general trend, fFEC followed the order Clear

Pashiardis S1, Kalogirou SA 1* and Pelengaris A2


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