title: [Author's reply].
authors.affiliation: Centro de Salud Torre Ramona, Zaragoza, Spain. Electronic address: jomimajo@ono.com.
authors.forename: M José
authors.initials: MJ
authors.lastname: Bruscas Alijarde
authors.affiliation: Centro de Salud Torre Ramona, Zaragoza, Spain.
authors.forename: Karlos
authors.initials: K
authors.lastname: Naberan Toña
authors.affiliation: Centro de Salud Torre Ramona, Zaragoza, Spain.
authors.forename: M Teresa
authors.initials: MT
authors.lastname: Lambán Sánchez
authors.affiliation: Centro de Salud Torre Ramona, Zaragoza, Spain.
authors.forename: Salvador
authors.initials: S
authors.lastname: Bello Dronda