[1] Cent Hosp Cent Finland, Dept Surg, Jyvaskyla 40620, Finland
[2] Univ Jyvaskyla, Sch Business & Econ, Jyvaskyla, Finland
[3] Cent Hosp Cent Finland, Dept Anesthesiol, Jyvaskyla 40620, Finland
[4] Turku Univ Hosp, Primary Hlth Care Unit, Dept Gen Practice, FIN-20520 Turku, Finland
[5] Helsinki Univ Hosp, Unit Primary Hlth Care, Helsinki, Finland