Cell Phones and Driving Performance: A Meta-Analysis

Abstract

A meta-analysis was conducted to explore the costs associated with cell phone use while driving, using standardized measures of effect size along five dimensions (moderator variables) that were hypothesized to impact the costs associated with cell phone use. Sixteen studies (contributing a total of 37 analysis entries) met the appropriate conditions for the meta-analysis. Overall, there were clear costs to driving performance when drivers are engaged in cell phone conversations. However, investigation of moderator variables indicated that these costs were borne primarily by reaction time tasks, with far smaller costs associated with tracking (lane keeping) performance. Hands-free and hand-held phones revealed similar patterns of results, as did simulator versus field studies. Conversation tasks tended to show greater costs to performance than did information-processing tasks (e.g., word games). Finally, costs in driving performance were roughly equivalent whether the conversation was with a passenger or whether over a cell phone.