Homma PCM, de Graaf C, Tan HL, et al. - In out-of-hospital cardiac arrest (OHCA), an automated external defibrillator (AED) is increasingly used for defibrillation and hence the presence of a shockable rhythm is recurrently only documented by the AED. Researchers here sought to ascertain 1) how frequently a shockable rhythm was recorded only in the AED; 2) if so, how regularly information that a shockable rhythm had been present reached the physician. They gathered data on OHCA cases with (presumed) cardiac cause with an AED connected in the years 2012-2014 (Study period 1) and 2016 (Study period 2) in the Amsterdam Resuscitation Study database. In Study period 1, they identified data concerning 2,840 OHCA CPR attempts with (presumed) cardiac cause; of these, 1,521 (54%) patients had a shockable rhythm, with 356 patients (13%) receiving AED defibrillation only. Among these patients, information concerning a shockable rhythm was not evident in 11 hospital discharge letters (4%). In Study period 2, AED defibrillation only was reported in 125/1,128 patients (11%); in two of these cases, the shockable rhythm was unknown by the physician. These findings suggest that a shockable rhythm is only seen on the AED-ECG in 11-13% of OHCAs. Despite the essentiality of adequate transfer to the physician of vital AED-information, it is not always accomplished.