title: Recall accuracy of mobile phone calls among Japanese young people.
abstract: This study aimed to elucidate the recall accuracy of mobile phone calls among young people using new software-modified phone (SMP) technology. A total of 198 Japanese students aged between 10 and 24 years were instructed to use a SMP for 1 month to record their actual call statuses. Ten to 12 months after this period, face-to-face interviews were conducted to obtain the self-reported call statuses during the monitoring period. Using the SMP record as the gold standard of validation, the recall accuracy of phone calls was evaluated. A total of 19% of the participants (34/177) misclassified their laterality (i.e., the dominant side of ear used while making calls), with the level of agreement being moderate (κ-statistics, 0.449). The level of agreement between the self-reports and SMP records was relatively good for the duration of calls (Pearson's r, 0.620), as compared with the number of calls (Pearson's r, 0.561). The recall was prone to small systematic and large random errors for both the number and duration of calls. Such a large random recall error for the amount of calls and misclassification of laterality suggest that the results of epidemiological studies of mobile phone use based on self-assessment should be interpreted cautiously.
authors.affiliation: Department of Public Health, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan.
authors.forename: Kosuke
authors.initials: K
authors.lastname: Kiyohara
authors.affiliation: Electromagnetic Compatibility Laboratory, Applied Electromagnetic Research Institute, National Institute of Information and Communications Technology, Koganei, Tokyo, Japan.
authors.forename: Kanako
authors.initials: K
authors.lastname: Wake
authors.affiliation: Electromagnetic Compatibility Laboratory, Applied Electromagnetic Research Institute, National Institute of Information and Communications Technology, Koganei, Tokyo, Japan.
authors.forename: Soichi
authors.initials: S
authors.lastname: Watanabe
authors.affiliation: Division of Advanced Electrical and Electronics Engineering, Tokyo University of Agriculture and Technology, Koganei-shi, Tokyo, Japan.
authors.forename: Takuji
authors.initials: T
authors.lastname: Arima
authors.affiliation: Department of Public Health, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan.
authors.forename: Yasuto
authors.initials: Y
authors.lastname: Sato
authors.affiliation: Department of Public Health, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Kojimahara
authors.affiliation: Department of Electrical Engineering, Graduate School of Engineering, Tokyo Metropolitan University, Hachioji, Tokyo, Japan.
authors.forename: Masao
authors.initials: M
authors.lastname: Taki
authors.affiliation: Department of Public Health, Tokyo Women's Medical University, Shinjuku-ku, Tokyo, Japan.
authors.forename: Naohito
authors.initials: N
authors.lastname: Yamaguchi
mesh_terms: D000293:Adolescent; D000328:Adult; D040421:Cell Phone / Q000706:statistics & numerical data; D002648:Child; D004423:Ear; D005260:Female; D006801:Humans; D007407:Interviews as Topic; D007564:Japan; D016015:Logistic Models; D008297:Male; D011939:Mental Recall; D015203:Reproducibility of Results; D057566:Self Report; D012984:Software; D013334:Students; D055815:Young Adult