LEADER 05801nam 2200805Ia 450 001 9910820205503321 005 20200520144314.0 010 $a9786612689574 010 $a9781282689572 010 $a1282689576 010 $a9780470840481 010 $a047084048X 010 $a9780470686140 010 $a0470686146 010 $a9780470871911 010 $a0470871911 035 $a(CKB)1000000000799845 035 $a(EBL)470770 035 $a(OCoLC)441887000 035 $a(SSID)ssj0000354704 035 $a(PQKBManifestationID)11276012 035 $a(PQKBTitleCode)TC0000354704 035 $a(PQKBWorkID)10314685 035 $a(PQKB)10321109 035 $a(MiAaPQ)EBC470770 035 $a(Au-PeEL)EBL470770 035 $a(CaPaEBR)ebr10341718 035 $a(CaONFJC)MIL268957 035 $a(OCoLC)320799869 035 $a(FINmELB)ELB179111 035 $a(Perlego)2766828 035 $a(EXLCZ)991000000000799845 100 $a20090617d2009 uy 0 101 0 $aeng 135 $aur|n|---||||| 181 $ctxt 182 $cc 183 $acr 200 10$aQuality of life outcomes in clinical trials and health-care evaluation $ea practical guide to analysis and interpretation /$fStephen Walters 205 $a1st ed. 210 $aChichester, West Sussex, U.K. ;$aHoboken [N.J.] $cJohn Wiley & Sons$dc2009 215 $a1 online resource (381 p.) 225 1 $aStatistics in practice 300 $aDescription based upon print version of record. 311 08$a9780470753828 311 08$a047075382X 320 $aIncludes bibliographical references and index. 327 $aQuality of Life Outcomes in Clinical Trials and Health-Care Evaluation; Contents; Preface; 1 Introduction; Summary; 1.1 What is quality of life?; 1.2 Terminology; 1.3 History; 1.4 Types of quality of life measures; 1.5 Why measure quality of life?; 1.6 Further reading; 2 Measuring quality of life; Summary; 2.1 Introduction; 2.2 Principles of measurement scales; 2.2.1 Scales and items; 2.2.2 Constructs and latent variables; 2.3 Indicator and causal variables; 2.3.1 Indicator variables; 2.3.2 Causal variables 327 $a2.3.3 Why do we need to worry about the distinction between indicator and causal items?2.3.4 Single-item versus multi-item scales; 2.4 The traditional psychometric model; 2.4.1 Psychometrics and QoL scales; 2.5 Item response theory; 2.5.1 Traditional scales versus IRT; 2.6 Clinimetric scales; 2.7 Measuring quality of life: Indicator or causal items; 2.8 Developing and testing questionnaires; 2.8.1 Specify the research question and define the target population; 2.8.2 Identify concepts; 2.8.3 Create instrument; 2.8.4 Assess measurement properties; 2.8.5 Modify instrument; 2.9 Further reading 327 $a3 Choosing a quality of life measure for your studySummary; 3.1 Introduction; 3.2 How to choose between instruments; 3.3 Appropriateness; 3.4 Acceptability; 3.5 Feasibility; 3.6 Validity; 3.6.1 Tests for criterion validity; 3.6.2 Tests for face and content validity; 3.6.3 Tests for construct validity; 3.7 Reliability; 3.7.1 Repeatability reliability; 3.7.2 Graphical methods for assessing reliability between two repeated measurements; 3.7.3 Internal reliability or internal consistency reliability; 3.8 Responsiveness; 3.8.1 Floor and ceiling effects; 3.9 Precision; 3.10 Interpretability 327 $a3.11 Finding quality of life instruments4 Design and sample size issues: How many subjects do I need for my study?; Summary; 4.1 Introduction; 4.2 Significance tests, P-values and power; 4.3 Sample sizes for comparison of two independent groups; 4.3.1 Normally distributed continuous data - comparing two means; 4.3.2 Transformations; 4.3.3 Comparing two groups with continuous data using non-parametric methods; 4.3.4 Dichotomous categorical data - comparing two proportions; 4.3.5 Ordered categorical (ordinal) data; 4.4 Choice of sample size method with quality of life outcomes; 4.5 Paired data 327 $a4.5.1 Paired continuous data - comparison of means4.5.2 Paired binary data - comparison of proportions; 4.6 Equivalence/non-inferiority studies; 4.6.1 Continuous data - comparing the equivalence of two means; 4.6.2 Binary data - comparing the equivalence of two proportions; 4.7 Unknown standard deviation and effect size; 4.7.1 Tips on obtaining the standard deviation; 4.8 Cluster randomized controlled trials; 4.9 Non-response; 4.10 Unequal groups; 4.11 Multiple outcomes/endpoints; 4.12 Three or more groups; 4.13 What if we are doing a survey, not a clinical trial? 327 $a4.13.1 Sample sizes for surveys 330 $aAn essential, up-to-date guide to the design of studies and selection of the correct QoL instruments for observational studies and clinical trials. Quality of Life (QoL) outcomes or Person/Patient Reported Outcome Measures (PROMs) are now frequently being used in randomised controlled trials (RCTs) and observational studies. This book provides a practical guide to the design, analysis and interpretation of studies that use such outcomes. QoL outcomes tend to generate data with discrete, bounded and skewed distributions. Many investigators are concerned about the appropriateness o 410 0$aStatistics in practice. 606 $aClinical trials 606 $aQuality of life 606 $aOutcome assessment (Medical care) 615 0$aClinical trials. 615 0$aQuality of life. 615 0$aOutcome assessment (Medical care) 676 $a610.72/4 700 $aWalters$b Stephen John$0731064 801 0$bMiAaPQ 801 1$bMiAaPQ 801 2$bMiAaPQ 906 $aBOOK 912 $a9910820205503321 996 $aQuality of life outcomes in clinical trials and health-care evaluation$93928360 997 $aUNINA