title: [Development of a New Scale for Gauging Smartphone Dependence].
abstract: OBJECTIVE
  We designed a scale to gauge smartphone dependence and assessed its reliability and validity.
  
  
  METHODS
  A prototype self-rating smartphone-dependence scale was tested on 133 medical students who use smartphones more frequently than other devices to access web pages. Each response was scored on a Likert scale (0, 1, 2, 3), with higher scores indicating greater dependence. To select items for the final scale, exploratory factor analysis was conducted.
  
  
  RESULTS
  On the basis of factor analysis results, we designed the Wakayama Smartphone-Dependence Scale (WSDS) comprising 21 items with 3 subscales: immersion in Internet communication; using a smartphone for extended periods of time and neglecting social obligations and other tasks; using a smartphone while doing something else and neglect of etiquette. Our analysis confirmed the validity of the different elements of the WSDS: the reliability coefficient (Cronbach's alpha) values of all subscales and total WSDS were from 0.79 to 0.83 and 0.88, respectively.
  
  
  CONCLUSIONS
  These findings suggest that the WSDS is a useful tool for rating smartphone dependence.
authors.affiliation: Department of Public Health, Wakayama Medical University, Wakayama, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Toda
authors.forename: Nobuhiro
authors.initials: N
authors.lastname: Nishio
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Takeshita
mesh_terms: D003858:Dependency, Psychological; D005163:Factor Analysis, Statistical; D006801:Humans; D011594:Psychometrics / Q000379:methods*; D015203:Reproducibility of Results; D000068997:Smartphone / Q000706:statistics & numerical data*; D013337:Students, Medical / Q000523:psychology*; D011795:Surveys and Questionnaires