Human Factors and Airway Management
CASE PRESENTATION Print Section Listen A lady in her thirties presented for endoscopic sinus surgery and septoplasty. Preoperative assessment found only a congenitally fused neck vertebra and use of nasal…
Confidence Intervals
Confidence Intervals: Introduction Print Section Listen All the statistical procedures developed so far were designed to help decide whether or not a set of observations is compatible with some hypothesis….
The Special Case of Two Groups: The t Test
The Special Case of Two Groups: The t Test: Introduction Print Section Listen As we have just seen in Chapter 3, many investigations require comparing only two groups. In addition,…
How to Analyze Survival Data
How to Analyze Survival Data: Introduction Print Section Listen All the methods that we have discussed so far require “complete” observations, in the sense that we know the outcome of…
What Does “Not Significant” Really Mean?
What Does “Not Significant” Really Mean?: Introduction Print Section Listen Thus far, we have used statistical methods to reach conclusions by seeing how compatible the observations were with the null…
How to Test for Differences between Groups
How to Test for Differences between Groups: Introduction Print Section Listen Statistical methods are used to summarize data and test hypotheses with those data. Chapter 2 discussed how to use…
How to Summarize Data
How to Summarize Data: Introduction Print Section Listen An investigator collecting data generally has two goals: to obtain descriptive information about the population from which the sample was drawn and…
Alternatives to Analysis of Variance and the t Test Based on Ranks
Alternatives to Analysis of Variance and the t Test Based on Ranks: Introduction Print Section Listen Analysis of variance, including the t tests, is widely used to test the hypothesis…
What Do the Data Really Show?
What Do the Data Really Show?: Introduction Print Section Listen The statistical methods we have been discussing permit you to estimate the certainty of statements and precision of measurements that…
Biostatistics and Clinical Practice
Biostatistics and Clinical Practice: Introduction Print Section Listen Until the second quarter of the 20th century, medical treatment had little positive effect on when, or even whether, sick people recovered….
