OBJECTIVE To develop a risk screening scale for medication adherence in anticoagulated patients and evaluate its reliability and validity， thereby providing an assessment tool for identifying medication adherence risks during anticoagulant therapy and implementing individualized interventions.METHODS Based on the protection motivation theory， a preliminary scale containing 20 items was developed through literature analysis， semi-structured interviews， expert consultation and a pilot survey. Convenience sampling was used to distribute questionnaires to patients receiving anticoagulant therapy at multiple medical institutions. Item analysis was conducted to select items. Exploratory factor analysis （EFA） and confirmatory factor analysis （CFA） were used to assess construct validity and further screen items. The New General Self-Efficacy Scale-Short Form （NGSES-SF） was used to assess criterion-related validity， and the internal consistency and split-half reliability of the scale were evaluated.RESULTS A total of 425 questionnaires were distributed， and 411 valid questionnaires were recovered， yielding an effective recovery rate of 96.71%. The final scale consisted of four dimensions：perceived severity， perceived susceptibility， response efficacy and self-efficacy， with a total of 11 items. EFA extracted four common factors， with a cumulative variance contribution rate of 68.805%. CFA showed the Chi-square degrees of freedom ratio was 1.839， the root mean square error of approximation was 0.064， the goodness-of-fit index was 0.945， the comparative fit index was 0.979， and the Tucker-Lewis index was 0.969. The total score of the scale and the scores of each dimension were significantly positively correlated with the scores of the criterion scale NGSES-SF （ P ＜0.05）， and the correlation coefficient between the total score of the scale and the total score of NGSES-SF was 0.346. The Cronbach’s α coefficient for internal consistency was 0.878， and the split-half reliability coefficient was 0.743.CONCLUSIONS The medication adherence risk screening scale for patients on anticoagulant therapy constructed in this study demonstrated good reliability and validity， which can be used to screen for medication adherence risk in patients on anticoagulant therapy， and serve as an assessment tool for stratified targeted interventions in clinical practice.