Author	Design	Method	Reason	Misplaced Electrode (Most Common listed first)	Clinical Significance of Misplacement	Result	Recommendation
Rajaganeshan et al. [13]	Multi-center Prospective cohort study, UK	119 medical personnel acquiring 12 lead ECG, Doctors, Nurses, Technicians, Physicians, cardiologists	Operator Error, anatomical differences, obesity	V1; V2; V4; V5; V6	Potentially harmful treatment/therapeutic procedures. Misclassifying ischemic changes	Wide inter-individual variation in placement	Training/education regarding correct identification of anatomical landmarks, positioning of electrodes and clinical implications
Wallen et al. [25]	Paramedic ECG acquisition, New Zealand	50 Female participants (Multi ethnicity) on and under the breast	Anatomical differences, Breast tissue	Modified placement owing to gender. Paramedics attitude to ECG acquisition with hesitance to expose female chest	Women with ACS potentially receive fewer cardiac investigations and less treatment than men	26 women (52%) preferred electrodes placed on breast, 19 (38%) were indifferent and 5 (10%) preferred under breast	Further research into views of women with cultural differing perspectives regarding electrode placement on breast tissue
Davis et al. [26]	PULSE, Multi-center Randomised clinical trial, USA, Canada and China	2,956 Patients (42% Female) from cardiac units in the USA, Canada and China. ECG monitoring education programme implementing AHA practice standards	Anatomical differences, gender, accuracy of precordial electrode placement	Precordial electrodes V1-V6	Alteration of waveform morphology, leading to misdiagnosis of arrhythmias and ischemia	Precordial (V-lead) placement did not differ by gender, however, <50% of men and women assessed had accurate electrode placement	Online education and strategies to change practice, improve nurse knowledge and QoC regarding ECG. Significant improvement concluded with implementation of AHA practice standards
Day et al. [27]	Single Centre retrospective study, USA	55 Patients 32 (58%) Male, 23 (42%) Female, each received chest computer tomography (CT) examination, reviewed for measurements to correctly identify 4^th intercostal space for accurate electrode placement	Obese patients, inaccurate palpation/identification of intercostal spaces	Sternal notch; Xiphoid process; 4^th Intercostal space; V1	Misinterpretation/ incorrect diagnosis of anterior infarction, anteroseptal infarction, ventricular hypertrophy, ischemia, Brugada syndrome	The measurement identified by the study may be utilized to identify the 4^th intercostal space for accurate placement of precordial electrodes	Use of the sternal notch and Xiphoid process, even in obese people, as reference points to accurately identify intercostal spaces, essential as remaining precordial electrodes are placed based on this initial electrode placement
Medani et al. [14]	Prospective pre- and post- intervention performance analysis study, Ireland	100 medical personnel, Doctors, Nurses, Technicians, randomly selected to place sticker dots on mannequin, recorded on radar plot and compared to correct precordial positions	To asses competence of placement, and improve performance through a peer-led educational intervention	Placing V1 and V2 too superiorly and V5 and V6 too medially	Erroneous diagnosis, poor R wave progression, poor reproducibility of ECG amplitude measurement, anteroseptal infarction and ventricular hypertrophy, alterations to QRS complex and T wave prominence and morphology. False positive and false negative ischemic changes on ECG	Placing V1 and V2 too superiorly and V5 and V6 too medially. Significant increase in accuracy post intervention with 80-85% homogeneity achieved compared to 34% on initial assessment	Educational intervention, periodic retraining, peer-led training either six-monthly or on an annual basis
Walsh [28]	5 x Case Presentations	Case 1: Patient presented to ED Case 2: Patient presented to primary care physician Case 3: Patient presented for routine medical evaluation Case 4: Patient presented to primary care physician Case 5: Patient presented to ED	Multi-factorial: V1 and V2 misplaced superiorly Obesity, clothing not removed, lead switching	V1 and V2 misplaced superiorly	Misplacement of V1 and V2 can produce false poor r wave progression, false Incomplete Right Bundle Branch Block (IRBBB), can suggest pulmonary embolism, Type 2 Brugada, anterior ST segment elevation, anterior T wave inversion	Cases identify the potential clinical ramifications associated with misplacement of precordial electrodes and leads	Awareness of misplacement
McCann et al. [10]	Prospective observational study	Assessment of ECG electrode placement in 77 patients as part of routine ED care	Operator error,	Wide spread inter-operator electrode placement variation, particularly lateral leads	Greater lateral chest electrode discordance noted for both male and female patients, than those of central chest electrodes. Electrode misplacement of 20mm or more is associated with significant QRS morphology that may affect clinical interpretation	Inter-operator variability. Physical identification of defined anatomical landmarks is an inexact science. Patient factors may further impede accurate location, particularly in older larger women. Even expert assessment of correct ECG electrode location/placement is not a reliable reference standard	Leaving chest electrodes in place throughout the patient’s hospital stay may help minimize variability, however, this may be uncomfortable, impracticable