Research in Communication Sciences and Disorders: Methods for Systematic Inqury Book

Preface ix

Chapter 1 Empirical and Nonempirical Research: An Overview 1

Systematic Inquiry 1

Some Roles for Research 2

Types of Research 4

Variables 6

Getting Started with Research 7

Summary 8

Chapter 2 Ethical Considerations 11

Protection of Human Participants 11

Special Protections 14

Historical Perspective 15

Institutional Review Boards 21

Credit for Intellectual Effort 21

Attribution of Ideas 22

Accuracy in Reporting Information 23

Avoiding Conflicts of Interest 24

Confidentiality and Privacy 25

Summary 26

Chapter 3 Identifying and Formulating Research Questions 31

Identifying Important Questions 31

Formulating Research Questions 34

Ways to Formulate a Research Problem 36

Evidence-Based Practice Questions 40

Criteria for Well-Formed Questions 42

Establishing Validity and Reliability 43

Summary 49

Chapter 4 Completing a Literature Search 53

Purposes of a Literature Search 53

Planning and Conducting a Search 55

Search Tools 55

Designing a Search Strategy 60

Organizing and Documenting Your Literature Search 61

Summary 64

Appendix Electronic Literature Search 69

Chapter 5 Nonexperimental Research Design 77

Nonexperimental Research Designs 77

Survey Research 78

Case Studies 80

Longitudinal Research 81

Correlation and Regression 81

Group Comparisons 82

Causal-Comparative Research 82

Qualitative Research 85

Ethnography 86

Grounded Theory 87

Case Study 88

Phenomenology 88

Scientific Rigor in Qualitative Research 89

Summary 91

Chapter 6 Experimental Research and Levels of Evidence 99

Experimental Research Designs 100

Posttest-Only Designs 101

Pretest-Posttest Randomized Control GroupDesign 102

Solomon Randomized Four-Group Design 103

Switching Replications Design 103

Factorial Designs 104

Importance of Experimental Control 109

History 110

Maturation 110

Statistical Regression 110

Instrumentation 111

Selection 111

Mortality 112

Quasi-Experimental Approaches 112

Nonequivalent Control Group Designs 113

Repeated Measures Group Design 114

Single Subject Designs 116

Experimental Designs and Levels of Evidence 123

Summary 125

Chapter 7 Research Participants and Sampling 131

Populations and Samples 131

Sample Characteristics 133

Sampling Methods 134

Simple Random Sampling 134

Systematic Sampling 135

Stratified Random Sampling 135

Cluster Sampling 137

Purposive Sampling 137

Random Assignment 138

Sample Size 140

Summary 142

Chapter 8 Data Analysis: Describing Different Types of Data 147

Levels of Measurement 147

Visual Representation of Data 149

Descriptive Statistics 153

Frequencies and Percentages 154

Measures of Central Tendency 156

Measures of Variability 158

Shapes of Distributions 160

Summary 162

Chapter 9 Data Analysis: Inferential Statistics 167

Inferential Statistics 167

Measures of Association 169

Pearson Product-Moment Correlation Coefficient 169

Coefficient of Determination 174

Spearman Rank-Order Correlation 174

Chi Square and Contingency Coefficient 175

Simple Regression and Multiple Regression 177

Testing for Differences between Two Samples 179

Independent and Paired T-Tests 180

Mann-Whitney U 184

Sign Test and Wilcoxin Matched-Pairs Signed-Ranks Test 184

Testing for Differences among Three or More Samples 185

Statistical Analysis for Factorial Designs 190

Summary 192

Chapter 10 Research Outcomes: Clinical Guidance, Research Reports 199

Knowledge Base for Evaluating Clinical Research 199

Critical Appraisal 200

How Applicable are the Findings 203

Significance of Results and Effect Size 205

Reporting Research Findings 206

Components of a Research Report 207

Writing Guidelines and Writing Style 209

Disseminating Research Findings 211

Summary 212

Index 217