[1] Castilla & Leon Publ Hlth Syst Sacyl, Unit Act Coping Strategies Pain Primary Care, East Valladolid Primary Care Management, Valladolid 47011, Spain
[2] Univ Valladolid, Fac Med, Dept Cell Biol Genet Hist & Pharmacol, Ave Ramon & Cajal 7, Valladolid 47005, Spain
[3] Univ Salamanca, Fac Nursing & Physiotherapy, Dept Nursing & Physiotherapy, Avda Donantes Sangre S-N, Salamanca 37007, Spain
[4] Univ Hosp Salamanca, P San Vicente 182, Salamanca 37007, Spain