TECHNICAL REPORT ON ITEM REDUCTION, FACTOR LOADINGS, AND OTHER INFORMATION ON PRINCIPAL COMPONENT ANALYSES SUMMARIZED IN

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1 TECHNICAL REPORT ON ITEM REDUCTION, FACTOR LOADINGS, AND OTHER INFORMATION ON PRINCIPAL COMPONENT ANALYSES SUMMARIZED IN Patrick DL, Bushnell DM, Rothman MR. (2004) Performance of Two Self Report Measures for Evaluating Obesity and Weight Loss. Obesity Research 12 (1):48-57 PCA Factor Analysis (Promax): OWLQOL 17 item Original Validation Dataset (n=340) Total % of Variance Cumulative % I have difficulty accepting my body BOMW I feel ugly BOMW I feel depressed BOMW I feel guilty when I eat BOMW I envy people who are thin I get discouraged when I try to lose weight I am bothered by what other people say about my weight BOMW, I try to wear clothes that hide my shape I am afraid that I will gain back any weight that I lose I feel frustrated that I am not able to eat what others do BOMW My weight prevents me from doing what I want to do I worry about the future BOMW I worry about the physical stress that my weight puts on my body I feel frustrated that I have less energy BOMW BOMW, I have to pay close attention to personal hygiene BOMW, I try to avoid having my photograph taken I feel that people stare at me BOMW Rotation Method: Promax with Kaiser Normalization. Correlation = 0.7

2 Random (1 st ) Half of OBES-002 Clinical Trial Dataset (n=641) Total % of Variance Cumulative % I feel ugly BOMW I have difficulty accepting my body BOMW I feel depressed BOMW I am bothered by what other people say about my weight BOMW, I try to avoid having my photograph taken I feel guilty when I eat BOMW BOMW, I try to wear clothes that hide my shape I feel that people stare at me BOMW I envy people who are thin I feel frustrated that I am not able to eat what others do BOMW I am afraid that I will gain back any weight that I lose I get discouraged when I try to lose weight I worry about the physical stress that my weight puts on my body I worry about the future BOMW My weight prevents me from doing what I want to do BOMW, I have to pay close attention to personal hygiene I feel frustrated that I have less energy BOMW Rotation Method: Promax with Kaiser Normalization. Correlation = 0.71

3 Random (2 nd ) Half of OBES-002 Clinical Trial Dataset (n=641) Extraction Sums of Squared Loadings Total % of Variance Cumulative % Total % of Variance Cumulative % I feel ugly BOMW I have difficulty accepting my body BOMW I feel depressed BOMW I am bothered by what other people say about my weight BOMW, I try to avoid having my photograph taken I feel guilty when I eat BOMW I feel frustrated that I am not able to eat what others do BOMW I feel that people stare at me BOMW I envy people who are thin BOMW, I try to wear clothes that hide my shape I am afraid that I will gain back any weight that I lose I get discouraged when I try to lose weight I worry about the future BOMW I worry about the physical stress that my weight puts on my body My weight prevents me from doing what I want to do BOMW, I have to pay close attention to personal hygiene I feel frustrated that I have less energy BOMW Rotation Method: Promax with Kaiser Normalization. Correlation = 0.71

4 U.S. Population Survey General Obese (Knowledge Networks Dataset) (n=989) Total % of Variance Cumulative % Matrix 1 36 I have difficulty accepting my body BOMW I feel depressed BOMW I feel ugly BOMW I am bothered by what other people say about my weight I feel guilty when I eat BOMW I worry about the physical stress that my weight puts on my body My weight prevents me from doing what I want to do I am afraid that I will gain back any weight that I lose BOMW, I try to avoid having my photograph taken I worry about the future BOMW I get discouraged when I try to lose weight I feel frustrated that I have less energy BOMW I feel that people stare at me BOMW I feel frustrated that I am not able to eat what others do BOMW BOMW, I try to wear clothes that hide my shape I envy people who are thin BOMW, I have to pay close attention to personal hygiene.667 a 1 components extracted.

5 European Population Survey General Obese (NFO Dataset) (n=2769) Total % of Variance Cumulative % Matrix 1 36 I have difficulty accepting my body BOMW I feel ugly BOMW I feel depressed BOMW I feel guilty when I eat BOMW I worry about the future BOMW I am bothered by what other people say about my weight BOMW, I try to avoid having my photograph taken My weight prevents me from doing what I want to do I feel that people stare at me BOMW I am afraid that I will gain back any weight that I lose I feel frustrated that I am not able to eat what others do BOMW I feel frustrated that I have less energy BOMW I worry about the physical stress that my weight puts on my body I get discouraged when I try to lose weight I envy people who are thin BOMW, I try to wear clothes that hide my shape BOMW, I have to pay close attention to personal hygiene.681 a 1 components extracted.