%0 Journal Article
%@ 2291-5222
%I JMIR Publications
%V 7
%N 3
%P e12171
%T Temporal Stability of Smartphone Use Data: Determining Fundamental Time Unit and Independent Cycle
%A Pan,Yuan-Chien
%A Lin,Hsiao-Han
%A Chiu,Yu-Chuan
%A Lin,Sheng-Hsuan
%A Lin,Yu-Hsuan
%+ National Health Research Institutes, Institute of Population Health Sciences, 35 Keyan Road, Zhunan, Miaoli County, Miaoli County, 35053, Taiwan, 886 37246166 ext 36383, yuhsuanlin@nhri.org.tw
%K temporal stability
%K smartphone use
%K smartphone addiction
%K smartphone
%K mobile phone
%D 2019
%7 26.03.2019
%9 Original Paper
%J JMIR Mhealth Uhealth
%G English
%X Background: Assessing human behaviors via smartphone for monitoring the pattern of daily behaviors has become a crucial issue in this century. Thus, a more accurate and structured methodology is needed for smartphone use research. Objective: The study aimed to investigate the duration of data collection needed to establish a reliable pattern of use, how long a smartphone use cycle could perpetuate by assessing maximum time intervals between 2 smartphone periods, and to validate smartphone use and use/nonuse reciprocity parameters. Methods: Using the Know Addiction database, we selected 33 participants and passively recorded their smartphone usage patterns for at least 8 weeks. We generated 4 parameters on the basis of smartphone use episodes, including total use frequency, total use duration, proactive use frequency, and proactive use duration. A total of 3 additional parameters (root mean square of successive differences, Control Index, and Similarity Index) were calculated to reflect impaired control and compulsive use. Results: Our findings included (1) proactive use duration correlated with subjective smartphone addiction scores, (2) a 2-week period of data collection is required to infer a 2-month period of smartphone use, and (3) smartphone use cycles with a time gap of 4 weeks between them are highly likely independent cycles. Conclusions: This study validated temporal stability for smartphone use patterns recorded by a mobile app. The results may provide researchers an opportunity to investigate human behaviors with more structured methods. 
%M 30912751
%R 10.2196/12171
%U http://mhealth.jmir.org/2019/3/e12171/
%U https://doi.org/10.2196/12171
%U http://www.ncbi.nlm.nih.gov/pubmed/30912751