title: Text messaging: are dependency and Excessive Use discretely different for Japanese university students?
abstract: Text messaging may be excessive and young people may be dependent on it. We distributed the Self-perception of Text-message Dependency Scale (STDS), Hospital Anxiety and Depression Scale (HADS), Temperament and Character Inventory (TCI), and Relationship Questionnaire (RQ) to 223 Japanese university students in a two-wave study, separated by a 5-month interval. The STDS yielded a three-factor structure. The STDS scores across the two measurement occasions were stable across time (except for the Relationship Maintenance subscale). A hierarchical cluster analysis suggested a three-class structure interpreted as Normal Users, Excessive Users, and Dependent Users. Excessive Users and Dependent Users were characterized by a young age at initial mobile phone use, more frequent use of text messaging, higher Novelty Seeking, and better Other-Model patterns of adult attachment. Unlike Excessive Users, Dependent Users were characterized by lower Self-directedness, poorer Self-Model of adult attachment, and higher anxiety and depression. The Excessive Users, but not the Dependent Users, were characterized by high Reward Dependence and Co-operativeness. The present study demonstrated that the STDS has a robust factor structure, good construct validity, and temporal stability (except for Relationship Maintenance subscale); students could be classified into normal, excessive, and Dependent Users of the text messaging; and Dependent Users were characterized by Excessive Use and personality immaturity.
authors.affiliation: Department of Clinical Behavioral Sciences, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan; Department of Public Health, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Xi
authors.initials: X
authors.lastname: Lu
authors.affiliation: Department of Public Health, Faculty of Life Sciences, Kumamoto University, Kumamoto, Japan.
authors.forename: Takahiko
authors.initials: T
authors.lastname: Katoh
authors.affiliation: Research Center of Applied Psychology, Chengdu Medical College, Chengdu, China.
authors.forename: Zi
authors.initials: Z
authors.lastname: Chen
authors.affiliation: Kyushu University of Nursing and Social Welfare, Tamana, Japan.
authors.forename: Toshiaki
authors.initials: T
authors.lastname: Nagata
authors.affiliation: Kitamura Institute of Mental Health Tokyo, 101 Akasaka 8-13-5, Minato, Tokyo 107-0057, Japan; Department of Psychiatry, Graduate School of Medicine, Nagoya University, Nagoya, Japan. Electronic address: kitamura@institute-of-mental-health.jp.
authors.forename: Toshinori
authors.initials: T
authors.lastname: Kitamura
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D001007:Anxiety; D016739:Behavior, Addictive / Q000175:diagnosis / Q000523:psychology*; D002605:Character; D016000:Cluster Analysis; D003863:Depression; D005163:Factor Analysis, Statistical; D005260:Female; D006801:Humans; D007564:Japan; D008297:Male; D010555:Personality Inventory; D015203:Reproducibility of Results; D012201:Reward; D012649:Self Concept; D013334:Students / Q000523:psychology*; D011795:Surveys and Questionnaires; D013694:Temperament; D060145:Text Messaging / Q000706:statistics & numerical data*; D013997:Time Factors; D014495:Universities; D055815:Young Adult
keywords: Cluster analysis; Mobile phone; Rating scale; Reliability; Text message dependency; Validity