Quantitative systematic review: Sources of inaccuracy in manually measured adult respiratory rate data

Abstract

Aims To identify the potential sources of inaccuracy in manually measured adult respiratory rate (RR) data and quantify their effects. Design Quantitative systematic review with meta‐analyses where appropriate. Data Sources Medline, CINAHL, and Cochrane Library (from database inception to 31 July 2019). Review Methods Studies presenting data on individual sources of inaccuracy in the manual measurement of adult RR were analysed, assessed for quality, and grouped according to the source of inaccuracy investigated. Quantitative data were extracted and synthesized and meta‐analyses performed where appropriate. Results Included studies (N = 49) identified five sources of inaccuracy. The awareness effect creates an artefactual reduction in actual RR, and observation methods involving shorter counts cause systematic underscoring. Individual RR measurements can differ substantially in either direction between observations due to inter‐ or intra‐observer variability. Value bias, where particular RRs are over‐represented (suggesting estimation), is a widespread problem. Recording omission is also widespread, with higher average rates in inpatient versus triage/admission contexts. Conclusion This review demonstrates that manually measured RR data are subject to several potential sources of inaccuracy. Impact RR is an important indicator of clinical deterioration and commonly included in track‐and‐trigger systems. However, the usefulness of RR data depends on the accuracy of the observations and documentation, which are subject to five potential sources of inaccuracy identified in this review. A single measurement may be affected by several factors. Hence, clinicians should interpret recorded RR data cautiously unless systems are in place to ensure its accuracy. For nurses, this includes counting rather than estimating RRs, employing 60‐s counts whenever possible, ensuring patients are unaware that their RR is being measured, and documenting the resulting value. For any given site, interventions to improve measurement should take into account the local organizational and cultural context, available resources, and the specific measurement issues that need to be addressed.

Novel wearable and contactless heart rate, respiratory rate, and oxygen saturation monitoring devices: a systematic review and meta‐analysis

“…This suggests that a significant amount of heterogeneity is related to the reference standard. For example, studies which employed manual counting as a reference standard tended to be more heterogeneous, in keeping with previous studies documenting their unreliability [81].…”

Fever, Tachypnea, and Monocyte Distribution Width Predicts Length of Stay for Patients with COVID-19: A Pioneer Study

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Characteristics of low acuity prehospital emergency patients with 48-h mortality, an observational cohort study

“…Recorded measured vital parameters may be subject to some uncertainty [ 33 ], especially SpO2 is dependent on the patient's peripheral perfusion, and the blood pressure measurement can vary greatly when taken in a moving vehicle. Counting the respiratory rate is probably rarely done conscientiously over one minute, but rather estimated with consequent misjudgments [ 34 ]. Automatic registration of respiratory rate using EtCO 2 measurement or ECG monitoring in the prehospital setting, with the current technology applied is practically useless, as it is extremely sensitive to the patient moving, talking, coughing, or being in a moving vehicle etc.…”