Before using the sample size calculator, there are two terms that you need to know. These are: confidence interval and confidence level. If you are not familiar with these terms, click here. To learn more about the factors that affect the size of confidence intervals, click here.Enter your...
Sample size estimation The minimum sample size was estimated at 167, using the size calculation formula with respect to our study type contained in the manual by Whitley and Ball [20]. We considered the prevalence of hyperuricemia in people with periodontal disease in the study by Joo et al....
Power analysis and sample size calculation are intensely debated topics in medical research. With increasing pressure on researchers, medical journals are demanding a priori power analysis or sample size calculation as an imperative part of a well-designed study. Consequently, study authors feel compelle...
2.3. Sample Size Calculation Epi-info software version 7.2.5. was used to calculate the sample size. Considering a population size of 744,590 Lebanese seniors (the elderly constitutes 11% of the population), an expected prevalence of 62.5% of Lebanese participants claiming to know about stroke ...
This can be demonstrated with the accompanying spss syntax (limit at significant test result.sps). These sort of calculations are applied by various online tools offering to calculate sample size. This approach ignores the concept of random sampling error, thus ignoring the essence of inferential ...
The exact conditional approach is widely available in the majority of statistical software (SAS, R, StatXact, Stata, SPSS, etc.). For a simple 2 × 2 table, the p-value calculation should not take a long time even for a large sample size. The data from Example 1.1 is used to ...
Several methods are available for sample size calculation for clinical trials when survival curves are to be compared using the logrank statistic. We discu... E Lakatos,KKG Lan - 《Statistics in Medicine》 被引量: 186发表: 1992年 Biostatistics in clinical trials / The second volume in the Wi...
Since this is our sample size, we conclude that no missing values are present. SPSS also calculates a mean and standard deviation but these are not meaningful for nominal variables so we'll just ignore them. Second, the preferred brands have rather unequal frequencies, casting some doubt upon ...
From the given population of N=10,000 units, using a SRSWOR scheme, we selected NITR=5000 samples each of size n in the range 50–200 with a step of 50 units. From a given sample of n units, we calculate the value of the sample correlation coefficient rxy|k, k=1,2,…,NITR. We...
I don't have access to SAS and am hoping someone can give me some code that will allow me to make this calculation in SYSTAT, SPSS or even Excel. Or, can someone recommend a free-standing executable or a web-based java program I can use for this? (Of course, I can always ask ...