How Readable Are Child Safety Seat Installation Instructions?

Abstract
Objectives. To measure the required reading level of a sample of child safety seat (CSS) installation instructions and to compare readability levels among different prices of CSSs to determine whether the lower cost seats to which low-income parents have greater access are written to a lower level of education. Methods. A CD-ROM containing CSS installation instructions was obtained from the National Highway Traffic Safety Administration. Pricing information was obtained for available models from an Internet-based company that provides comparative shopping information. Paper copies of the instruction sets were generated, and their readability levels were determined using the SMOG test. A second rater was used in addition to the primary investigator to assess interrater reliability of the SMOG as applied to the instruction sets. Results. The readability of instruction sets ranged from the 7th- to 12th-grade levels, with an overall mean SMOG score of 10.34. No significant associations were found to exist between readability and seat prices; this was observed whether the data were treated as continuous or categorical. Conclusions. CSS instruction manuals are written at a reading level that exceeds the reading skills of most American consumers. These instruction sets should be rewritten at a lower reading level to encourage the proper installation of CSSs.