The purpose of the Emergency Medical Services Outcomes Project (EMSOP) is to develop a foundation and framework for out-of-hospital outcomes research. In prior work, this group delineated the priority conditions, described conceptual models, suggested core and risk adjustment measures potentially useful to emergency medical services research, and summarized out-of-hospital pain measurement. In this fifth article in the EMSOP series, the authors recommend specific risk-adjustment measures and outcome measures for use in out-of-hospital research on patients presenting with respiratory distress. The methodology included systematic literature searches and a structured review by an expert panel. The EMSOP group recommends use of pulse oximetry, peak expiratory flow rate, and the visual analog dyspnea scale as potential risk-adjustment measures and outcome measures for out-of-hospital research in patients with respiratory distress. Furthermore, using mortality as an outcome measure is also recommended. Future research is needed to alleviate the paucity of validated tools for out-of-hospital outcomes research.