| Objective. Older adults, family members, and professionals may benefit from a driver's self/proxy-report designed to accurately assess safe driving behaviors. The objective of this study is to report on item development and validity testing of a self-report older adult Safe Driving Behavior Measure (SDBM).;Method. Based on theoretical frameworks (Precede-Proceed Model of Health Promotion, Haddon's matrix and Michon's model), existing driving measures, previous research, and guided by measurement theory, we: (1) developed items capturing safe driving behavior, establishing face validity using peer reviewers and content validity using expert raters. (2) conducted focus groups to evaluate or generate items based on respondents' driving experiences and refine the SDBM items based on feedback. Older drivers (mean age 70.5, SD=4.5) and family members (mean age 50, SD=20) participated in three focus groups in Florida and 13 Ontario. Using content and thematic analyses, we coded responses to existing items, new items, or revisions, and (3) evaluated the concurrent criterion validity of the SDBM using Receiver Operating Characteristic (ROC) analyses to compare ratings from older drivers, caregivers, and driving evaluators.;Results. Peer review indicated acceptable face validity. Initial expert rater review yielded a scale content validity index (CVI) rating of 0.78, with 44/60 items rated ≥ 0.75. Sixteen unacceptable items (≤ 0.5) required major revision or deletion. The next CVI scale average was 0.84 indicating acceptable content validity. Focus group one and two findings supported 46 of 72 existing items and generated 16 new items. Focus group three findings supported 40 existing items and generated 13 item revisions. Based on ROC analyses, SDBM ratings by evaluators resulted in the highest area under the curve (AUC) of 0.99. Family members/caregivers' ratings resulted in an AUC of 0.67. Drivers' ratings resulted in the lowest AUC of .54.;Conclusion. Initial findings expert review and focus group findings suggest the SDBM may be a relevant and useful driving self/proxy-report for older adults. However, based on results of the Receiver Operating Characteristic analyses, only the driving evaluator ratings on the SDBM have acceptable accuracy, as measured by AUC. Future testing will focus identifying items that are more predictive of driving ability and refining SDBM items (e.g., content or wording) to address rater bias and improve rating accuracy of the drivers and family members/caregivers. |
