Condition such as a disease, before and after a diagnostic test, respectively. The result of the diagnostic test could be either positive or negative. In reality, the subjectivity of the probabilities is merely based on a piece of information, whether an individual has a condition or not. The condition is regarded as a psychological phenomenon to those who go through a certain diagnostic test. In addition, the probability is always a 0 per cent or a 100 per cent result. The difference between the pretest and posttest probabilities on a certain condition is a major factor in the diagnostic test.
Confidence interval is commonly used in newspaper or television for its opinion poll results, a plus-or-minus figure. The level of confidence is expressed as a percentage that corresponds to the percentage of the population within the confidence interval. In politics, confidence intervals play a significant role. During political campaign period, polls taken from the public, often allow a 95 per cent confidence interval. The true population proportion of people that will vote a certain party lie within the confidence interval. The 95 per cent confidence level means that the poll is 95 per cent certain. Most often in research, 95 per cent is commonly used and it is a generally accepted standard. However, a researcher can calculate confidence interval at any level of significance such as 90 per cent or 99 per cent. The accuracy of the confidence interval is not numerically attached to how confident is a researcher, instead the confidence interval is a modifier to the interval itself and the 95 per cent confidence interval is more accurate. The researcher could possibly conclude that the result within the interval is the true value and accurate.
The Journal of Clinical Microbiology described a method for determining confidence intervals for a commonly used index of diversity. This approach facilitates the comparison of the genetic population structure of microorganisms isolated from different environments and improves the objective assessment of the discriminatory power of typing techniques. Among the 117 carriage strains from the community, 57 types by macro restriction analysis are distinguished. Of 117 carriage strains obtained from the hospital population, 55 types are distinguished. The genetic diversity of carriage strains in the community was 97.6 per cent, with a confidence interval of 96.8 to 98.5 per cent, and for carriage strains from hospital patients, it equaled 89.5 per cent, with a confidence interval of 84.4 to 94.7 per cent, the confidence interval did not overlap. An estimation of confidence intervals when calculating the index of diversity greatly aids the comparison of genetic diversity in different environments, as well as the ability to address objectively the discriminatory potential of diverse typing systems.
Reference:
Hajo Grundmann, Satoshi Hori, and Gregor Tanner. “Determining Confidence Intervals When Measuring Genetic Diversity and the Discriminatory Abilities of Typing Methods for Microorganisms.” Journal of Clinical Microbiology 39.11 (2001): 4190-4192. Web. 21 Aug. 2001
