TY - JOUR
T1 - Average vs item response theory scores
T2 - an illustration using neighbourhood measures in relation to physical activity in adults with arthritis
AU - Mielenz, T. J.
AU - Callahan, L. F.
AU - Edwards, M. C.
N1 - Funding Information:
Manuscript preparation was supported by an American College Rheumatology Research and Education Foundation Health Professional New Investigator Award, a North Carolina Chapter's Arthritis Foundation New Investigator Award and the Foundation for Physical Therapy New Investigator Fellowship Training Initiative . This research project was supported by a grant from the National Institute of Arthritis and Musculoskeletal and Skin Disease, Multidisciplinary Clinical Research Center, Rheumatic Diseases : P60-AR49465-01 . This research was supported in part by Contract Number 1IP2PI000797-01 from PCORI. All statements in this report, including its findings and conclusions, are solely those of the authors and do not necessarily represent the views of the PCORI, its Board of Governors or Methodology Committee. This research was also supported in part by the National Center for Injury Prevention and Control , Centers for Disease Control and Prevention to the Center for Injury Epidemiology and Prevention at Columbia University ( R49 CE002096-01 ). Its contents are solely the responsibility of the authors and do not necessarily represent the official views of the National Institutes of Health and Centers for Disease Control and Prevention.
Publisher Copyright:
© 2016 The Royal Society for Public Health
PY - 2017/1/1
Y1 - 2017/1/1
N2 - Objectives Our study had two main objectives: 1) to determine whether perceived neighbourhood physical features are associated with physical activity levels in adults with arthritis; and 2) to determine whether the conclusions are more precise when item response theory (IRT) scores are used instead of average scores for the perceived neighbourhood physical features scales. Methods Information on health outcomes, neighbourhood characteristics, and physical activity levels were collected using a telephone survey of 937 participants with self-reported arthritis. Neighbourhood walkability and aesthetic features and physical activity levels were measured by self-report. Adjusted proportional odds models were constructed separately for each neighbourhood physical features scale. Results We found that among adults with arthritis, poorer perceived neighbourhood physical features (both walkability and aesthetics) are associated with decreased physical activity level compared to better perceived neighbourhood features. This association was only observed in our adjusted models when IRT scoring was employed with the neighbourhood physical feature scales (walkability scale: odds ratio [OR] 1.20, 95% confidence interval [CI] 1.02, 1.41; aesthetics scale: OR 1.32, 95% CI 1.09, 1.62), not when average scoring was used (walkability scale: OR 1.14, 95% CI 1.00, 1.30; aesthetics scale: OR 1.16, 95% CI 1.00, 1.36). Conclusion In adults with arthritis, those reporting poorer walking and aesthetics features were found to have decreased physical activity levels compared to those reporting better features when IRT scores were used, but not when using average scores. This study may inform public health physical environmental interventions implemented to increase physical activity, especially since arthritis prevalence is expected to be close to 20% of the population in 2020. Based on NIH initiatives, future health research will utilize IRT scores. The differences found in this study may be a precursor for research on how past and future treatment effects may vary between these two types of measurement scores.
AB - Objectives Our study had two main objectives: 1) to determine whether perceived neighbourhood physical features are associated with physical activity levels in adults with arthritis; and 2) to determine whether the conclusions are more precise when item response theory (IRT) scores are used instead of average scores for the perceived neighbourhood physical features scales. Methods Information on health outcomes, neighbourhood characteristics, and physical activity levels were collected using a telephone survey of 937 participants with self-reported arthritis. Neighbourhood walkability and aesthetic features and physical activity levels were measured by self-report. Adjusted proportional odds models were constructed separately for each neighbourhood physical features scale. Results We found that among adults with arthritis, poorer perceived neighbourhood physical features (both walkability and aesthetics) are associated with decreased physical activity level compared to better perceived neighbourhood features. This association was only observed in our adjusted models when IRT scoring was employed with the neighbourhood physical feature scales (walkability scale: odds ratio [OR] 1.20, 95% confidence interval [CI] 1.02, 1.41; aesthetics scale: OR 1.32, 95% CI 1.09, 1.62), not when average scoring was used (walkability scale: OR 1.14, 95% CI 1.00, 1.30; aesthetics scale: OR 1.16, 95% CI 1.00, 1.36). Conclusion In adults with arthritis, those reporting poorer walking and aesthetics features were found to have decreased physical activity levels compared to those reporting better features when IRT scores were used, but not when using average scores. This study may inform public health physical environmental interventions implemented to increase physical activity, especially since arthritis prevalence is expected to be close to 20% of the population in 2020. Based on NIH initiatives, future health research will utilize IRT scores. The differences found in this study may be a precursor for research on how past and future treatment effects may vary between these two types of measurement scores.
KW - Arthritis
KW - Average scores
KW - Item response theory scores
KW - Perceived neighbourhood physical features
KW - Physical activity
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U2 - 10.1016/j.puhe.2016.08.016
DO - 10.1016/j.puhe.2016.08.016
M3 - Article
C2 - 28057192
AN - SCOPUS:84996587551
SN - 0033-3506
VL - 142
SP - 15
EP - 21
JO - Public Health
JF - Public Health
ER -