Statistics for the Health Sciences

′Statistics for the Health Sciences engagingly presents the key analytic issues that students and professionals need to understand in the most accessible and vivid way possible. Full of real examples and practical exercises, the book successfully avoids getting bogged down with complex maths and formulae′ - Dennis Howitt at Loughborough University The chapter overviews, absence of statistical formulae and use of appropriate examples and student exercises make this a very ′hands on′ and practical text′ - Merryl E Harvey, Birmingham City University

• PART ONE: AN INTRODUCTION TO THE RESEARCH PROCESS OverviewThe Research ProcessConcepts and VariablesLevels of MeasurementHypothesis TestingEvidence-Based PracticeResearch DesignsMultiple-Choice QuestionsPART TWO: COMPUTER-ASSISTED ANALYSISOverviewOverview of the Three Statistical PackagesIntroduction to SPSSSetting out Your Variables for within - and between-Group Designs Introduction to RIntroduction to SASSummaryExercisesPART THREE: DESCRIPTIVE STATISTICSOverviewAnaylsing DataDescriptive StatisticsNumerical Descriptive StatisticsChoosing a Measure of Central TendencyMeasures of Variation or DispersionDeviations from the MeanNumerical Descriptives in SPSSGraphical StatisticsBar ChartsLine GraphsIncorporating Variability into GraphsGenerating Graphs with Standard Deviations in SPSSGraphs Showing Dispersion - Frequency HistogramBox-PlotsSummarySPSS ExerciseMultiple Choice QuestionsPART FOUR: THE BASIS OF STATISTICAL TESTINGOverviewIntroductionSamples and PopulationsDistributionsStatistical SignificanceCriticisms of NHSTGenerating Confidence Intervals in SPSSSummarySPSS ExerciseMultiple Choice QuestionsPART FIVE: EPIDEMIOLOGYOverviewIntroductionEstimating the Prevalence of DiseaseDifficulties in Estimating PrevalenceBeyond Prevalence: Identifying Risk Factors for DiseaseRisk RatiosThe Odds-RatioEstablishing CausalityCase-Control StudiesCohort StudiesExperimental DesignsSummaryMultiple Choice QuestionsPART SIX: INTRODUCTION TO DATA SCREENING AND CLEANINGOverviewIntroductionMinimising Problems at the Design StageEntering Data into Databases/Statistical PackagesThe Dirty DatasetAccuracyUsing Descriptive Statistics to Help Identify ErrorsMissing DataSpotting Missing DataNormalityScreening Groups SeparatelyReporting Data Screning and Cleaning ProceduresSummaryMultiple Choice QuestionsPART SEVEN: DIFFERENCES BETWEEN TWO GROUPSOverviewIntroductionConceptual Description of the t-TestsGeneralising to the PopulationIndependent Groups t-Test in SPSSCohen′s dPaired t-Test in SPSSTwo-Sample z-TestNon-Parametric TestsMann-Whitney: for Independent GroupsMann-Whitney Test in SPSSWilcoxon Signed Rank Test: For Repeated MeasuresWilcoxon Signed Rank Test in SPSS Adjusting for Multiple TestsSummaryMultiple Choice QuestionsPART EIGHT: DIFFERENCES BETWEEN THREE OR MORE CONDITIONSOverviewIntroductionConceptual Description of the (Parametric) ANOVAOne-Way ANOVAOne-way ANOVA in SPSSANOVA Models for Repeated-Measures DesignsRepeated Measures ANOVA in SPSS Non-parametric EquivalentsThe Kruskal-Wallis TestKruskal-Wallis and the Median Test in SPSS The Median TestFriedman′s ANOVA for Repeated MeasuresFriedman′s ANOVA in SPSSSummaryMultiple Choice QuestionsPART NINE: TESTING ASSOCIATIONS BETWEEN CATEGORICAL VARIABLESOverviewIntroductionRationale of Contingency Table AnalysisRunning the Analysis in SPSSMeasuring Effect Size in Contingency Table AnalysisLarger Contingency TablesContingency Table Analysis AssumptionsThe X2 Goodness of Fit TestRunning the X2 Goodness of Fit Test Using SPSSSummaryMultiple Choice QuestionsPART TEN: MEASURING AGREEMENT: CORRELATIONAL TECHNIQUESOverviewIntroductionBivariate RelationshipsPerfect CorrelationsCalculating the Correlation Pearson′s R Using SPSS.How to obtain Scatterplots Variance Explanation of RObtaining Correlational Analysis in SPSS: ExercisePartial CorrelationsShared and Unique Variance: Conceptual Understanding Relating to Partial CorrectionsSpearman′s RhoOther uses for Correlational TechniquesReliability of Measures Internal ConsistencyInter Rater ReliabilityValidityPercentage AgreementCohen′s KappaSummaryMultiple Choice QuestionsPART 11: LINEAR REGRESSION OverviewIntroductionLinear Regression in SPSSObtaining teh Scatterplot with Regression Line and Confidence Intervals in SPSSAssumptions Underlying Linear RegressionDealing with OutliersWhat happens if the Correlation Between X and Y is Near Zero?Using Regression to Predict Missing Data in SPSSPrediction of Missing Scores on Cognitive Failures in SPSSSummaryMultiple-Choice QuestionsPART TWELVE: STANDARD MULTIPLE REGRESSION OverviewIntroductionMultiple Regression in SPSSVariables in the EquationThe Regression EquationPredicting an Individual′s ScoreHypothesis TestingOther Types of Multiple RegressionHierarchical Multiple RegressionSummaryMultiple Choice QuestionsPART THIRTEEN: LOGISTIC REGRESSIONOverviewIntroductionThe Conceptual Basis of Logistic RegressionWriting up the ResultLogistic Regression with Multiple Predictor Variables Logistic Regression with Categorical PredictorsCategorical Predictors with Three or More LevelsSummaryMultiple Choice QuestionsInterventions and Analysis of ChangeOverviewInterventionsHow do we Know Whether Interventions are Effective?Randomised Control Trials (RCTs)Designing an RCT: CONSORTThe CONSORT Flow ChartImportant Features of an RCTBlindingAnalysis of RCTsRunning an ANCOVA in SPSSMcNemar′s Test of ChangeRunning McNemar′s Test in SPSSThe Sign TestRunning the Sign Test using SPSSIntention to Treat AnalysisCrossover DesignsSingle Case Designs (N= 1)Generating Single Case Design Graphs Using SPSSSummarySPSS ExerciseMultiple Choice QuestionsPART FIFTEEN: SURVIVAL ANALYSIS: AN INTRODUCTIONOverviewIntroductionSurvival CurvesThe Kaplan-Meier Survival FunctionKaplan-Meier Survival Analyses in SPSSComparing Two Survival Curves - the Mantel-Cox testMantel-Cox using SPSSHazardHazard CurvesHazard Functions in SPSSWriting up a Survival AnalysisSummarySPSS ExerciseMultiple Choice Questions