Understanding the reasons for refusal of polio vaccine by families in Quetta Block, Pakistan. - Zarak MS; Sana H; Arshad Z; Saleem A; Shah M; Tareen H; Ullah S; Baloch S; Kakar S; Kakar K (Eastern Mediterranean health journal = La revue de sante de la Mediterranee orientale = al-Majallah al-sihhiyah li-sharq al-mutawassit, 2022)