A Comparison of Two Methods to Assess Mobile Hand-Held Communication Device Use

The purpose of this study was to: 1) examine the agreement between self-reported measures of mobile hand-held device use and direct measures, and 2) understand how respondents think about their device use when completing the questionnaire. 35 participants were recruited from a Canadian university to participate. The questionnaire was previously developed to estimate six types of usage potentially related to musculoskeletal disorders in cell phone users. Direct measures were collected on a custom software usage logging application resident on the participants’ phone. Bland-Altman plots demonstrated that, generally speaking, participants’ self-reports overestimated their logged usage; overestimates tended to be low at low mean usage times, and became more variable as mean usage time increased. Six themes were identified from the interviews: 1) types of mobile hand-held devices, 2) tasks attributed to different categories of device use, 3) their thought process used to arrive at usage, 4) ease of reporting usage, 5) physical interaction with device, and 6) completeness of list of categories of device use. The preliminary findings indicate that it may be challenging for respondents to provide good self-reports of usage. The root of this challenge does not appear lie with the design of the questionnaire; rather, it may be attributed to the respondents’ difficulty in estimating usage, partly due to the variability of device use both within a day and a week.