TY - JOUR
T1 - Modeling daily and weekly moderate and vigorous physical activity using zero-inflated mixture Poisson distribution
AU - Xue, Xiaonan
AU - Qi, Qibin
AU - Sotres-Alvarez, Daniela
AU - Roesch, Scott C.
AU - Llabre, Maria M.
AU - Bainter, Sierra A.
AU - Mossavar-Rahmani, Yasmin
AU - Kaplan, Robert
AU - Wang, Tao
N1 - Publisher Copyright:
© 2020 John Wiley & Sons Ltd
PY - 2020/12/30
Y1 - 2020/12/30
N2 - Recently developed accelerometer devices have been used in large epidemiological studies for continuous and objective monitoring of physical activities. Typically, physical movements are summarized as minutes in light, moderate, and vigorous physical activities in each wearing day. Because of preponderance of zeros, zero-inflated distributions have been used for modeling the daily moderate or higher levels of physical activity. Yet, these models do not fully account for variations in daily physical activity and cannot be extended to model weekly physical activity explicitly, while the weekly physical activity is considered as an indicator for a subject's average level of physical activity. To overcome these limitations, we propose to use a zero-inflated Poisson mixture distribution that can model daily and weekly physical activity in same family of mixture distributions. Under this method, the likelihood of an inactive day and the amount of exercise in an active day are simultaneously modeled by a joint random effects model to incorporate heterogeneity across participants. If needed, the method has the flexibility to include an additional random effect to address extra variations in daily physical activity. Maximum likelihood estimation can be obtained through Gaussian quadrature technique, which is implemented conveniently in an R package GLMMadaptive. Method performances are examined using simulation studies. The method is applied to data from the Hispanic Community Health Study/Study of Latinos to examine the relationship between physical activity and BMI groups and within a participant the difference in physical activity between weekends and weekdays.
AB - Recently developed accelerometer devices have been used in large epidemiological studies for continuous and objective monitoring of physical activities. Typically, physical movements are summarized as minutes in light, moderate, and vigorous physical activities in each wearing day. Because of preponderance of zeros, zero-inflated distributions have been used for modeling the daily moderate or higher levels of physical activity. Yet, these models do not fully account for variations in daily physical activity and cannot be extended to model weekly physical activity explicitly, while the weekly physical activity is considered as an indicator for a subject's average level of physical activity. To overcome these limitations, we propose to use a zero-inflated Poisson mixture distribution that can model daily and weekly physical activity in same family of mixture distributions. Under this method, the likelihood of an inactive day and the amount of exercise in an active day are simultaneously modeled by a joint random effects model to incorporate heterogeneity across participants. If needed, the method has the flexibility to include an additional random effect to address extra variations in daily physical activity. Maximum likelihood estimation can be obtained through Gaussian quadrature technique, which is implemented conveniently in an R package GLMMadaptive. Method performances are examined using simulation studies. The method is applied to data from the Hispanic Community Health Study/Study of Latinos to examine the relationship between physical activity and BMI groups and within a participant the difference in physical activity between weekends and weekdays.
KW - latent variable
KW - negative binomial distribution
KW - overdispersion
KW - proportional odds model
KW - zero-inflated distribution
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U2 - 10.1002/sim.8748
DO - 10.1002/sim.8748
M3 - Article
C2 - 32949036
AN - SCOPUS:85091023958
SN - 0277-6715
VL - 39
SP - 4687
EP - 4703
JO - Statistics in Medicine
JF - Statistics in Medicine
IS - 30
ER -