Using Research and Statistics in Health Care *14

this topic addresses the following learning objectives: * Explain the role of research in developing knowledge for use in health care evidence-based practice situations. * Identify several ways that research can influence healthcare policy. * Identify peer-reviewed healthcare research articles. * Differentiate between descriptive and inferential research questions in a peer-reviewed article on healthcare research. * Identify the problem statement/purpose/aim in a peer-reviewed article on healthcare research. * Identify the theoretical or conceptual framework used in a peer-reviewed article on healthcare research. * Differentiate between Anderson’s model of
* Interpret frequency tables, bar charts, histograms, stem-and-leaf plots, frequency polygons, and cumulative frequency polygons in healthcare statistics. * Describe variables in healthcare-related research using appropriate measures of central tendency, dispersion, shape, and skewness. * Explain the proper use of percentiles in healthcare research.

A variable is any characteristic that can and does assume different values for the different people, objects, or events being studied
In measuring variables, four basic types of measurement are used: categorization, rank ordering, interval ordering, and numerical scoring. Each of these types of measurement corresponds to one of four measurement scales: nominal (categorization), ordinal (rank ordering), interval (interval ordering), and ratio (numerical scoring)
Sometimes nominal variables are called categorical or qualitative.
Examples of nominal variables are gender, ethnicity, religion, marital status, region of residence, adhering to an appointment. Note that the numbers could just as easily be assigned differently
All subjective rating scales are considered ordinal, including satisfaction scales, ratings of pain or discomfort, symptom checklists to evaluate psychological states such as depression, and so on including Likert scale.
A good example of an interval scale is the PHQ-2 (Kroenke, Spitzer, & Williams, 2003), a