Drivers’ Mistakes When Installing Child Seats

This study examined the mistakes that drivers made during the different steps taken to install Child Restraint Systems (CRS). The focus of this study was to identify the reasons drivers made installation mistakes. The participants were observed during their CRS installation process where unfolding installation errors lead to clues about why participants had difficulty with their installation. Five experiments were conducted to identify common errors installing CRS using seat belts or the attachment system known as Lower Anchors and Tethers for Children (LATCH). The investigation examined the factors that contribute to these errors and identified possible improvements that could reduce them. In experiments 1 and 2, 61 participants completed an infant CRS installation to the best of their ability using the original CRS instruction manual and their vehicle owner’s manual. Participants were asked to use a “talkaloud” method, where they explained whatever they were examining, thinking, doing, and feeling as they went about their task. The CRS installation was video-taped with their consent. Participants rated their confidence levels, ease of installation, and CRS usability after the installations were completed. All participants who installed the child seat using the seat belt made at least one error. There was a 95% error rate for participants who completed the infant CRS installation using LATCH. Participants expressed confusion with a feature on the CRS or vehicle approximately two times for each seat belt and LATCH installation. In experiment 3, 22 participants completed a rear-facing and forward-facing installation with a convertible CRS. Common installation problems were loose installation (85%), incorrect seat angling (81.8%), and twisted lower anchor straps (50%). Studies 4 and 5 explored CRS installations by parents and caregivers at child seat inspection events and from parents and caregivers found from local community postings. The installation errors reflected similar common errors found in studies 1-3 but to a lesser degree. Loose installation error rate ranged from 46.7 percent to 65 percent (seat belt or LATCH) and incorrect angling ranged from 27 to 50 percent in studies 4 and 5, respectively. As participants installed the child seats, they acknowledged the difficulty in installing the CRS into the vehicle and with interpreting the manuals but were overly confident that they correctly installed the CRS. Analyses were conducted on the installation errors made by installation type, feature differences across the child seats used, and user ratings.