tailieunhanh - How to Display Data- P6

How to Display Data- P6:The best method to convey a message from a piece of research in health is via a fi gure. The best advice that a statistician can give a researcher is to fi rst plot the data. Despite this, conventional statistics textbooks give only brief details on how to draw fi gures and display data. | Chapter 3 Displaying univariate categorical data Describing categorical data This chapter will concentrate on appropriate ways of displaying categorical d that is data that can be catr hri d a o groups such as blond group or disease severity. An initial step whendescribingcategoricaldataisto counttha number of observations in eachcatogory anOnxpenrsihnm ae pearentages sO She total samplr size. Son enample Table contains categorical data from a self-completei postal gdeetionnasey survey ofntw mothses aptenxia mately 8 weekt post One oi the questionn tda mothers were aiVad was What ktnd nO etlivory did yon OrveC Ti pisp 3iy catagorinai dnta asccSc as these we can uit rithve po blasts os bar apart . NoVe tiort Oisce ertrgo-ries are ordered Uysizerit isimmed atly onvi tusssd ieV artthemrstiSsast frequent cateoories. Table Self-reported type ofde I very fornew mothersp 3221 1 What kind of delivery Number in each category Normal vaginaldelivery 2221 Emergency caesarean section 434 once labourhadstarted Planned caesarean section 251 Ventouse vacuumextractord 210 Forceps delivery 89 Vaginal breec h delivery 16 Total 3221 Pie charts Figure displays the data in Table as a pie chart so-called because it resembles a pie cut into pieces for serving . Each segment in the pie chart f 7 18 How to Display Data O Normal vaginal delivery 69 O Ventouse O Emergency caesarean section 1 O Forceps delivery O Planned caesarean section H Vaginal breech delivery _ Figure Pie chart ofself-reported typeofdeliveryfor all new mothers using shading to distinguish beUween different categ ories 3221 . represents anindividualcptegoey. TheaoeadispSoycdOogeach canego ey is proportional tothu numbet inthat category. A piecl-asOfsconoti u cyedby dividing a circle into sectors with each sector or segment representing a different category. .