Sample size: from formulae to concepts

Sample size can be calculated from many online calculators or tables. But the use of these instruments is rational only when we understand our input data and the concept behind them completely. Terminologies like confidence interval, confidence limit, standard error of mean, margin of error, standard normal variate, power, significance level etc. and extent to which population size or chances of occurrence of an outcome can affect our sample size remain to be well understood before using these software solutions

Sample size: from formulae to concepts - II

Sample size formulae need some input data or to say it otherwise we need some parameters to calculate sample size. This second part on the formula explanation gives ideas of Z, population size, precision of error, standard deviation, contingency etc which influence sample size

Small size sampling?

Though small size samples can be planned and justified based on scarcity of time, money and manpower, there are situations making more accuracy a must and needing larger samples sizes. That’s why rare adverse drug reactions are identified only after a drug comes into the market and a large population is exposed to it. There are many more reasons for increasing the sample size and requirement of the study decides which criteria of accuracy should be tightened the most (e.g. avoiding type I error is more important or type II error)

Small size sampling

Based on the law of large numbers which is derived from probability theory, we tend to increase the sample size to the maximum. Central limit theorem is another inference from the same probability theory which approves largest possible number as sample size for better validity of measuring central tendencies like mean and median. Sometimes increase in sample-size turns only into negligible betterment or there is no increase at all in statistical relevance due to strong dependence or systematic error. If we can afford a little larger sample, statistically power of 0.90 being taken as acceptable with medium Cohen’s d (<0.5) and for that we can take a sample size of 175 very safely and considering problem of attrition 200 samples would suffice

Microbial xylanases and their biomedical applications: a review

Xylanases have a great potential, mainly known for industrial applications. They can hydrolyze the xylose (Hemicellulose of plant cell wall) and can be used for bio-bleaching the kraft pulp. As it reduces the requirement of harsh chemicals in the process, it can be used further to a number of bio-products with a great aggregate value. Microbial-origin xylanases can also be used in improving the nutritional quality of animal feed (e.g. food additives to poultry, piggery or fishery) and indirectly affect the humans. Additionally they can be used directly in human food in bakery, clarification of juices and in xenobiotics like tobacco processing. The great value of xylanase as a bio-bleaching agent has now a new dimension of fiber digesting agent having relevance to food, drugs and cosmetics act. This review presents some important applications of Xylanases extended up to biomedical sciences

Pre- & post- bronchodilator pulmonary function test in Indian females: a survey in and around Jaipur

Background: Nonsmoker COPD in people is a continued point of concern. Recent standards prescribe that spirometry should be population specific, recent origin and methodically derived (prescribed by GOLD) with influencing factors specified – which this study aims to do.Methods: From a random sample of 4,500 adults, subjects were invited into study through a 16 point questionnaire. After inclusion/ exclusion criteria applied to 3,733 total responders, 244 rural and 240 urban healthy non-smoker females were enrolled. Spirometry with reproducibility testing before and after bronchodilator (salbutamol) was done as per GOLD prescription. As normality of distribution was disproved, non-parametric methods were used in statistics. Results: Mean FEV1 and FVC were 2.25 and 2.69 liters respectively in rural females, while it was 2.06 and 2.44 liters in urban females. Post-bronchodilator (after 0.3 mg salbutamol) values in rural females were 2.32 and 2.70 liters respectively while the same were 2.13 and 2.45 liters in urban cases.Conclusion: PFT of rural females resulted better on FEV1 and FVC, pre as well as post-bronchodilator. Possibly biomass fuel exposure in the rural females might not be causing a generalized decrease in PFT parameters or urban chemical pollution which might have more than counterbalanced in urban side.

Governance & Corruption – Developments and Issues in Ethiopia

This paper reports the results of a survey of 400 respondents in Ethiopia about factors generating corruption and the potential of e-Governance to mitigate corruption. It is suggested that e-Governance can help not only in weeding out corruption but also in the establishment of sounder government citizen relationships in Ethiopia. While e-Governance cannot cure all the structural factors that breed corruption in the society, strategic implementation of e-Governance can help improve the critical variable in combating corruption—government citizen relationships. It isargued that while e-Governance initiatives can make important contributions to improving public services they can best do so by helping improve overall relationships between governments and citizens

Prevalence of G6PD deficiency versus oxidizing drugs: a survey in the tertiary care hospital

Background: G6PD deficiency is distributed worldwide including India and is involved in accidental hemolysis and anemia by inadvertent use of oxidizing drugs. Awareness of community wise occurrence of G6PD deficiency can help in screening beforehand.Methods: On 150 community wise classified, non-anemic, non- hemolysed (in recent past) visitors of pathological laboratory attached to C U Shah Medical College, Surendranagar, Gujarat, Crayman’s hemoglobin colorimetric kit (item no 700540) was used to estimate normal or below normal status of G6PD.Results: 10 people (6.6% of population) were found deficient – 7 (4 male + 3 female) from Harijan community, 2 (1 male + 1 female) from Rabbari community and 1 (1 male + 0 female) from Lohana community.Conclusions: While applying oxidizing drugs in a person of Harijan community (prevalence 7 out of total 26, i.e. 27%), extra caution is required, esp. if a person otherwise vulnerable (e.g. alcoholic). For other less represented communities, larger stratified sampling is required

Comparative trends of accidental to intentional mortalities over a one-year period at a tertiary care centre

Background: The trends of deaths due to unnatural incidents are on the rise each year throughout the world, including India. Incremental trends have been observed in all mortalities throughout the country. Although all these mortalities seem preventable, yet not much has been achieved over the years. Intentional mortalities are yet more preventable as compared to non intentional ones. The trends of unnatural deaths were observed at a tertiary care centre of the capital city of Rajasthan to determine the comparative magnitude of such fatalities to predict possible reasons for them.Methods: An observational study was carried out for a one year period (2013-14) at the Department of Forensic Medicine of an apex institution of the capital metropolitan city to determine the comparative trends of accidental to suicidal and homicidal deaths amongst the medico-legal autopsies carried out over the study period. The results were analysed to look into the probable reasons for these preventable deaths.Results: Accidental fatalities contributed maximally followed by suicides and homicides. All types of unnatural deaths were more commonly observed in young adult male population. Road accidents were the major offenders followed by thermal injuries and falls. Intentional fatalities due to self harm or other human beings shared a considerable burden among unexpected mortalities over the study region.Conclusions: Majority of the reported fatalities were preventable deaths occurring amongst the active and productive population and hence, it is of utmost importance to analyse such deaths to suggest remedial measures bring down the toll of such causalities

Citizens’ Perceptions of Corruption and E - Governance in Jordan, Ethiopia, and Fiji — the Need for a Marketing Approach

The purpose of this research is to assess citizen’s perceptions of corruption and e-governance in Jordan, Ethiopia, and Fiji. The research is based on surveys using structured questionnaires and focus group interviews. Conclusions are derived from a mix of descriptive and inferential analysis. The survey covers a total of 1212 respondents using stratified sampling. Findings reveal that public sector corruption and demands for bribes are increasing in each country. Only a few people are aware of e-governance and feel that it can help in curbing corruption. The study proposes that in order to mitigate negative forces in the implementation of e-governance such as corruption, digital divide, and urban bias, developing countries need to apply a marketing approach to e-governance services