Abstract: Objective To develop a self-rating scale of venous thromboembolism (VTE) risk for home-based elderly people, to test its reliability and validity, and to provide reference for the risk assessment of venous thromboembolism for the elderly at home. Methods Based on Virchow’s triad, the original item pool was developed after literature review. After expert correspondence, hierarchical analysis and pre-debugging, the initial scale was developed. From July 2021 to April 2022, convenience sampling was used to select 200 elderly people from a community in Jinan and 100 VTE patients from a tertiary grade-A hospital in Shandong province for the validation of the scale. Results The recovery rate in the first and second expert letter consultation was 85% and 100%, respectively. The authority coefficient was 0.940 and 0.957 (both > 0.700), and Kendall’s W 0.351 and 0.420, respectively (both P<0.001). The developed scale consisted of 3 first-level, 9 second-level and 27 third-level items. The score of 5 was the optimal diagnostic threshold, with the area under the ROC curve was 0.965[95%CI:(0.947,0.984), P<0.001]. The retest reliability of the scale was 0.922(P<0.001), and the Kuder-Richardson formula 20 value 0.744 (>0.700). The item-level content validity of the scale was all > 0.850, and the scale level content validity 0.970. The correlation between the evaluation results of the scale and the gold standard diagnosis was 0.718 (P<0.001). Conclusion The developed self-rating scale for the risk of venous thromboembolism for the elderly at home shows good practicability and provides reference for the risk assessment of venous thromboembolism for the elderly at home.

Key words: elderly people, venous thrombosis, risk assessment, Delphi technique