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Table 5 Baseline to post-randomisation follow-up correlations by outcome

From: Sample size estimation for randomised controlled trials with repeated assessment of patient-reported outcomes: what correlation between baseline and follow-up outcomes should we assume?

Outcome Pearson baseline to post-randomisation follow-up correlation
Mean Median SD Minimum Maximum No. of correlations
B-IPQ 0.6 0.6 0 0.6 0.61 2
BACK PAIN 0.24 0.19 0.11 0.17 0.37 3
Barthel Score 0.53 0.53 0.1 0.45 0.6 2
BPRS 0.57 0.57 0.12 0.49 0.65 2
CORE Functioning Dimension 0.56 0.57 0.02 0.54 0.58 3
CORE Risk Dimension 0.26 0.27 0.07 0.19 0.32 3
CORE Symptoms Dimension 0.5 0.49 0.03 0.47 0.54 3
CORE Total Score 0.55 0.53 0.03 0.53 0.58 3
CORE Well Being Dimension 0.5 0.49 0.03 0.47 0.53 3
EORTC Appetite Loss 0.29 0.3 0.09 0.21 0.37 4
EORTC Cognitive Functioning 0.49 0.49 0.08 0.4 0.59 4
EORTC Constipation 0.39 0.4 0.08 0.3 0.48 4
EORTC Diarrhoea 0.25 0.27 0.07 0.16 0.32 4
EORTC Dyspnoea 0.43 0.44 0.06 0.35 0.49 4
EORTC Emotional Functioning 0.51 0.5 0.06 0.46 0.6 4
EORTC Fatigue 0.56 0.56 0.06 0.49 0.63 4
EORTC Financial Difficulties 0.63 0.62 0.07 0.56 0.74 4
EORTC Insomnia 0.44 0.49 0.12 0.26 0.52 4
EORTC Nausea 0.21 0.18 0.06 0.16 0.3 4
EORTC Pain 0.48 0.48 0.08 0.39 0.58 4
EORTC Physical Functioning 0.59 0.58 0.07 0.52 0.68 4
EORTC QoL 0.55 0.57 0.08 0.44 0.61 4
EORTC Role Functioning 0.54 0.54 0.04 0.5 0.59 4
EORTC Social Functioning 0.51 0.5 0.06 0.43 0.59 4
EPDS 0.49 0.49 0.04 0.47 0.52 2
EQ-5D Utility Score 0.55 0.54 0.13 0.32 0.87 29
EQ-5D VAS 0.41 0.46 0.2 −0.13 0.67 21
GSES 0.52 0.56 0.08 0.44 0.58 3
LEG PAIN 0.16 0.11 0.16 0.04 0.34 3
MFI General Fatigue 0.18 0.18 NA 0.18 0.18 1
MFI Mental Fatigue 0.53 0.53 NA 0.53 0.53 1
MFI Physical Fatigue 0.5 0.5 NA 0.5 0.5 1
MFI Reduced Activity 0.65 0.65 NA 0.65 0.65 1
MFI Reduced Motivation 0.61 0.61 NA 0.61 0.61 1
ODI 0.36 0.36 0.05 0.31 0.41 3
ONS Well-Being 0.62 0.62 NA 0.62 0.62 1
PHQ9 0.66 0.66 0.08 0.53 0.76 6
PISQ-31 Behaviour/Emotion 0.73 0.73 NA 0.73 0.73 1
PISQ-31 Partner Related Factor 0.63 0.63 NA 0.63 0.63 1
PISQ-31 Physical Factor 0.35 0.35 NA 0.35 0.35 1
PISQ-31 Total Score 0.62 0.62 NA 0.62 0.62 1
SF-36 General Health 0.6 0.58 0.08 0.49 0.79 29
SF-36 Mental Component Summary 0.54 0.55 0.12 0.33 0.79 17
SF-36 Mental Health 0.57 0.57 0.11 0.37 0.83 27
SF-36 Pain 0.49 0.51 0.13 0.2 0.71 29
SF-36 Physical Component Summary 0.56 0.6 0.21 0.14 0.84 17
SF-36 Physical Functioning 0.64 0.63 0.17 0.01 0.91 29
SF-36 Role-Emotional 0.42 0.43 0.11 0.12 0.68 31
SF-36 Role-Physical 0.39 0.35 0.12 0.21 0.67 29
SF-36 Social Functioning 0.44 0.45 0.1 0.24 0.63 29
SF-36 Vitality 0.55 0.53 0.1 0.43 0.82 29
SF-36 Health Change 0.32 0.32 0.11 0.24 0.4 2
SF-6D 0.5 0.48 0.09 0.37 0.64 14
Sleep Apnoea QoL 0.56 0.6 0.12 0.35 0.65 5
SPADI 0.47 0.47 0.03 0.44 0.5 3
SPADI Disability 0.49 0.51 0.06 0.43 0.54 3
SPADI Pain 0.36 0.38 0.05 0.31 0.4 3
VAS Pain 0.41 0.41 0.07 0.33 0.48 4
WOMAC Pain 0.26 0.26 NA 0.26 0.26 1
WOMAC Physical Function 0.46 0.46 NA 0.46 0.46 1
WOMAC Stiffness 0.09 0.09 NA 0.09 0.09 1