AGREEMENT AMONG RATERS IN ASSESSMENT OF PHYSIOLOGICAL WAVE-FORMS RECORDED BY A CARDIORESPIRATORY MONITOR FOR HOME-USE

There are numerous reports of cardiorespiratory patterns in infants on home monitors, but no data to determine whether ''experts'' agree on the description of these patterns. Therefore, we evaluated agreement a mong four experienced investigators and five trained technicians who a ssessed independently the same sample of physiologic waveforms recorde d from infants enrolled in a multicenter study. The monitor used respi ratory inductance plethysmography and recorded waveforms for apnea gre ater than or equal to 16 s or a heart rate <80 beats/min for greater t han or equal to 5 s. The investigators and technicians initially asses sed 88 waveforms. After additional training, the technicians assessed another 113 additional waveforms. In categorizing waveforms as apnea p resent or absent, agreement among technicians improved considerably wi th additional training (kappa 0.65 to 0.85), For categorizing waveform s as having bradycardia present versus absent, the trends were the sam e. Agreement in measurement of apnea duration also improved considerab ly with additional training (intraclass correlation 0.33-0.83). Agreem ent in measurement of bradycardia du ration was consistently excellent (intraclass correlation 0.86-0.99), Total agreement was achieved amon g technicians with additional training for measurement of the lowest h eart rate during a bradycardia, When classifying apnea as including gr eater than or equal to 1, greater than or equal to 2, greater than or equal to 3, or greater than or equal to 4 out-of-phase breaths, agreem ent was initially low, but after additional training it improved, espe cially in categorization of apneas with greater than or equal to 3 or greater than or equal to 4 out-of-phase breaths (kappa 0.67 and 0.94, respectively). Although researchers and clinicians commonly describe e vents based on cardiorespiratory recordings, agreement amongst experie nced individuals may be poor, which can confound interpretation. With clear guidelines and sufficient training raters can attain a high leve l of agreement in describing cardiorespiratory events.