Reliability and validity of the Safe Routes to school parent and student surveys

BACKGROUND: The purpose of this study is to assess the reliability and validity of the U.S. National Center for Safe Routes to School's in-class student travel tallies and written parent surveys. Over 65,000 tallies and 374,000 parent surveys have been completed, but no published studies have examined their measurement properties. METHODS: Students and parents from two Charlotte, NC (USA) elementary schools participated. Tallies were conducted on two consecutive days using a hand-raising protocol; on day two students were also asked to recall the previous days' travel. The recall from day two was compared with day one to assess 24-hour test-retest reliability. Convergent validity was assessed by comparing parent-reports of students' travel mode with student-reports of travel mode. Two-week test-retest reliability of the parent survey was assessed by comparing within-parent responses. Reliability and validity were assessed using kappa statistics. RESULTS: A total of 542 students participated in the in-class student travel tally reliability assessment and 262 parent-student dyads participated in the validity assessment. Reliability was high for travel to and from school (kappa > 0.8); convergent validity was lower but still high (kappa > 0.75). There were no differences by student grade level. Two-week test-retest reliability of the parent survey (n = 112) ranged from moderate to very high for objective questions on travel mode and travel times (kappa range: 0.62 - 0.97) but was substantially lower for subjective assessments of barriers to walking to school (kappa range: 0.31 - 0.76). CONCLUSIONS: The student in-class student travel tally exhibited high reliability and validity at all elementary grades. The parent survey had high reliability on questions related to student travel mode, but lower reliability for attitudinal questions identifying barriers to walking to school. Parent survey design should be improved so that responses clearly indicate issues that influence parental decision making in regards to their children's mode of travel to school.