1 Department of Biomedicine and Prevention, University of Rome "Tor Vergata", Via Montpellier, 1, 00133 Rome, Italy. Electronic address: ercole.vellone@uniroma2.it.
2 Department of Psychology, Sapienza University, Rome, Italy.
3 Oregon Health & Science University, School of Nursing Portland Campus, Portland, OR, USA.
4 School of Nursing, University of Pennsylvania, Philadelphia, PA, USA.