Developing a Single-Item General Self-Efficacy Scale: An Initial Study

General self-efficacy represents the global sense of personal capability across various situations and tasks. The aim of the present study was to develop and validate a single-item general self-efficacy scale which balances practical demands and psychometric concerns. The psychometric properties of the proposed Single-Item General Self-Efficacy Scale (GSE-SI) were examined among 231 Singaporean adults. Results based on three statistical methods demonstrated good reliability (.594 .607 and .726, respectively, M = .642), as compared with the reliability scores from other single-item scales. It also showed satisfactory criterion-related validity evidence (i.e., correlation with a multiple-item general self-efficacy scale, r = .795). Validity evidence based on relationships with other constructs was supported by the correlations between the scores of general self-efficacy and the scores of six relevant constructs (i.e., positive correlations with life satisfaction and positive emotions, negative correlations with negative emotions, task and perceived stress, and illness symptoms). More importantly, the GSE-SI and multiple-item scale scores showed consistent correlation patterns with their relevant constructs. Both GSE-SI and multiple-item scale scores significantly discriminated between the three clusters in a similar pattern. The present results show that the GSE-SI is a reliable and valid measure of general self-efficacy and can be recommended in future research to complement the constraints of multiple-item scales.