AHS375_Su11_u08 - 7/7/2011 CASE STUDY 5 See excel document...

Info iconThis preview shows pages 1–3. Sign up to view the full content.

View Full Document Right Arrow Icon
7/7/2011 1 UNIT 8 Statistical Tools Control Studies CASE STUDY 5 See excel document under unit 9 2 CHAPTER 10—STATISTICAL TOOLS 3 Copyright 2008 Health Administration Press. All rights reserved. TWO KINDS OF STATISTICAL TOOLS o Descriptive epidemiology o Describes characteristics of population o Health needs o Health events 4 Copyright 2008 Health Administration Press. All rights reserved. o Health outcomes o Inferential epidemiology o Compares two or more populations for differences or similarities LEVELS OF MEASUREMENT o Two classes of data o Continuous o Distance between points meaningful o Variable can take any value between points o Age, height, weight, blood pressure 5 Copyright 2008 Health Administration Press. All rights reserved. o Categorical o Variables take values in fixed number of categories o Ordinal—categories can be ordered in some way o Patient satisfaction —from “not satisfied” to “very satisfied” o Nominal—categories are “qualitative” o Race, gender SAMPLING o When can’t collect data from whole population o Subset of population provides estimate o Sample is drawn from a “sampling frame” or list of those available to be sampled—e.g., telephone book o Convenience sample o Nonrandom selection, e.g., first 50 to enter clinic 6 Copyright 2008 Health Administration Press. All rights reserved. o Probability sample o Uses concept of randomness o Uses some random mechanism to draw sample from sampling frame o Each member in sample equally as likely to be chosen o Systematic sampling o e.g., Randomly choose one of first 20 patient charts, then every 20th chart thereafter to get a 5 percent sample o Stratified random sampling o Stratify sample into categories (e.g., age within gender) and then randomly sample from within each category
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
7/7/2011 2 DESCRIPTIVE STATISTICS FOR CONTINUOUS VARIABLES o Measures of central tendency o Mean average value o Median—half observation below, half above 7 Copyright 2008 Health Administration Press. All rights reserved. o Measures of dispersion or variation o Standard deviation—average distance that variables fall from the mean o Variance is square of standard deviation o Range—distance from lowest to highest value HOW TO CALCULATE STANDARD DEVIATION o Subtract the mean, , from each value, X o Square the resulting number for each value o Add up those squares and divide that sum by the number of values minus 1 o Take the square root of that X 8 Copyright 2008 Health Administration Press. All rights reserved. s XX n nX X nn i i n ii i n i n    () ( ) 2 1 22 1 1 11 DESCRIPTIVE STATISTICS FOR CATEGORICAL VARIABLES o A frequency distribution presented graphically Proportion number with 9 Copyright 2008 Health Administration Press. All rights reserved.
Background image of page 2
Image of page 3
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 08/21/2011 for the course AHS 375 taught by Professor Elder during the Summer '11 term at University of Alabama at Birmingham.

Page1 / 11

AHS375_Su11_u08 - 7/7/2011 CASE STUDY 5 See excel document...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online