Effectiveness of Self-Help Plus in its digital version in reducing anxiety and post-traumatic symptomatology among nursing home workers during the COVID-19 pandemic: secondary analysis of randomised controlled trial data - Purgato, Marianna; Tedeschi, Federico; Riello, Marianna; Zaccoletti, Debora; Mediavilla, Roberto; Ayuso-Mateos, Jose Luis; Mactaggart, David; Barbui, Corrado; Rusconi, Elena (BMJ mental health, 2025)