Evidence-Based Practice for Nurses

CHAPTER OBJECTIVES KEY TERMS At the end of this chapter, you will be able to: ‹ Define statistics ‹ Differentiate between descri ...

At the end of this section, you will be able to: ‹ Define statistics ‹ Differentiate between descriptive and inferential statist ...

and synthesize collected data. Calculations and information presented with descriptive statistics must be accurate. Inferential ...

KEY TERMS bivariate analysis: The use of statistics to describe the relationship between two variables multivariate analysis: Th ...

shows how raw data are tallied and the resulting frequencies and percentages are recorded. The left-hand side of the table shows ...

it easier to understand, it also results in some loss of information. The grouped data presented in Table 13-3 indicate that 30% ...

FIGURE 13-1 Frequency Polygon and Histogram of Age Data 2 4 5 3 1 7 6 0 18–19 20–21 22–23 24–25 >25 Age (in years) 18–19 20–2 ...

Measures of central tendency offer another way to describe raw data. These measures provide information about the “typical” case ...

Ungrouped Data Grouped Data Age Tally Frequency Age Tally Percentage 18 ||| 3 18–19 |||| | 6 19 ||| 3 20–21 |||| | 6 20 | 1 22–2 ...

this formula gives only the position, and not the actual value, of the median. For example, in a study describing the number of ...

When reading articles in which averages are used, nurses must carefully examine the conclusions drawn. For example, suppose a nu ...

Normal Distributions: Symmetrical Shapes Measures of central tendencies are used to define distribution patterns. When the distr ...

A number of human traits, such as intelligence and height, are considered to be normally distributed in the population. When Dat ...

When there is greater variation in data, a wider spread results. In graphic rep- resentations of data (see Figure 13-5), highly ...

True/False If the tail of a distribution is skewed to the left, the data are negatively skewed. In a normal distribution, the m ...

range, percentile, and standard deviation. z scores and variance are used to compare the variability among data using different ...

FIGURE 13-6 Semiquartile Range of Age Data Q 1 = 19 Median = 21 Q 3 = 22.5 1818 18 19 19 19 20 21 21 21 21 21 22 22 22 23 23 25 ...

salary values. Calculating a standard deviation provides different information about variability. It is now apparent that the av ...

Do you have a professor who uses means and standard deviations, known as norm referencing, for grading exams? What are the advan ...

34% of the scores above and 34% of the scores below the mean to total 68%; two standard deviations contain 34% plus 13.5% above ...