Pediatr Blood Cancer 2014;61:956
LETTER TO THE EDITOR Physical Activity (PA) and Sleep Among Children and Adolescents with Cancer
To the Editor: We thank Dr. Kawada for his comments to our article [1]. In reviewing the results of our multivariate analysis and based on the relative standard error between models with and without the repeated statement, our effective sample size is between 100 and 110. After removing the two covariates that added the least to the models, the resulting estimates were very similar to the original ones. Thus, we are confident about our initial results. However, in the course of reviewing our models, we found better fitting models for “Morning Mood” using a different covariance structure (Compound Symmetry). In these new models, none of our activity measures was associated with Morning Mood. We measured physical activity levels quantitatively by actigraphy using the Actiwatch2 (Respironics1, Murrysville, PA). The Actiwatch Activity Monitoring System uses an algorithm based on preset criteria to determine sleep or wake for each epoch. Immobile or sedentary time was defined by the Respironics1 software as number of minutes per day with activity counts
LETTER TO THE EDITOR Physical Activity (PA) and Sleep Among Children and Adolescents with Cancer
To the Editor: We thank Dr. Kawada for his comments to our article [1]. In reviewing the results of our multivariate analysis and based on the relative standard error between models with and without the repeated statement, our effective sample size is between 100 and 110. After removing the two covariates that added the least to the models, the resulting estimates were very similar to the original ones. Thus, we are confident about our initial results. However, in the course of reviewing our models, we found better fitting models for “Morning Mood” using a different covariance structure (Compound Symmetry). In these new models, none of our activity measures was associated with Morning Mood. We measured physical activity levels quantitatively by actigraphy using the Actiwatch2 (Respironics1, Murrysville, PA). The Actiwatch Activity Monitoring System uses an algorithm based on preset criteria to determine sleep or wake for each epoch. Immobile or sedentary time was defined by the Respironics1 software as number of minutes per day with activity counts
