Background and Purpose: Current measures of missed nursing care employ inventories of tasks which are rated for the frequency with which each is missed. These lists have shortcomings for research and clinical evaluation. There is a need for measures with less response burden, wider generalizability, and greater sensitivity and specificity for identifying poor quality care. Methods: We tested a single-item, global, measure using data from a large study of missed care in Australia. We employed traditional and innovative analysis techniques such as receiver operating characteristic curve and item response theory. Results: The single-item measure had adequate concurrent and convergent validity when compared to one list-format measure of missed care and strong sensitivity and specificity for identifying poor quality care. Conclusions: A well-crafted single-item measure, such as the one tested, can be useful for measuring missed nursing care.