Post on 08-Dec-2014
description
Statistics & research Statistics & research methods for cliniciansmethods for clinicians
Ramez Reda MoustafaRamez Reda Moustafa
ObjectivesObjectives
Introduce statistical and research methods Introduce statistical and research methods commonly used in the medical sciencescommonly used in the medical sciencesBreak the psychological barrierBreak the psychological barrierIntroduce the basics of scientific writing Introduce the basics of scientific writing and publishing in medicineand publishing in medicine
What this course is notWhat this course is not
A comprehensive course on statisticsA comprehensive course on statisticsA series of lecturesA series of lectures
What I am notWhat I am not
A statisticianA statistician
TYPES OF DATATYPES OF DATA
Categorical - NominalCategorical - Nominal Yes/NoYes/No Male/FemaleMale/Female Red/White/BlackRed/White/Black
OrdinalOrdinal mild/moderate/severemild/moderate/severe Low/normal/highLow/normal/high
TYPES OF DATATYPES OF DATA
Continuous (quantitative, numerical)Continuous (quantitative, numerical) AgeAge Blood pressureBlood pressure ESRESR
What type?What type?
Glasgow coma scaleGlasgow coma scaleModified Rankin scaleModified Rankin scaleHbHbSplenomegalySplenomegalyFeverFeverDysphasiaDysphasia
SamplesSamples
Related or independent, that is the Related or independent, that is the question. question.
CategoricalCategorical Ordinal or Non-Normal Ordinal or Non-Normal ContinuousContinuous Normal ContinuousNormal Continuous
One sampleOne sample Chi-squared testChi-squared test Kolmogorov-Smirnov testKolmogorov-Smirnov test one sample t-testone sample t-test
Two samplesTwo samples independentindependent Chi-squared or Fisher's exact Chi-squared or Fisher's exact testtest Mann-Whitney U testMann-Whitney U test Student t-testStudent t-test
pairedpaired McNemar's testMcNemar's test Wlcoxon Signed Rank testWlcoxon Signed Rank test Paired t-testPaired t-test
Multiple samples Multiple samples (k>2)(k>2) independentindependent Chi-squared testChi-squared test Kruskal-Wallis testKruskal-Wallis test ANOVAANOVA
relatedrelated Cochran-Q testCochran-Q test Friedman testFriedman test repeated measures ANOVArepeated measures ANOVA
VarianceVariance
N=1 studiesN=1 studies100% studies100% studies
CICISDSDSEMSEM
Sample sizeSample size
The “N”The “N”Pilot studiesPilot studies
Summarizing dataSummarizing data
The MeanThe MeanThe MedianThe MedianFrequency/proportionFrequency/proportion
Answering questionsAnswering questions
1.1. Asking the questionAsking the question2.2. What is my dataWhat is my data3.3. The methodThe method4.4. Hypothesis testing or notHypothesis testing or not
Collecting dataCollecting data
Lab bookLab bookformsformsSource dataSource dataComputerComputer ExcelExcel SPSSSPSS
The table(s)The table(s)Master sheet? What master sheet?Master sheet? What master sheet?
Collecting dataCollecting data
Too many variablesToo many variablesToo few variablesToo few variables
Looking through your dataLooking through your data
TablesTablesGraphsGraphsDescriptive statsDescriptive stats