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Den Überlegungen zur Auswahl der Kontrollgruppe kommt in der Planungsphase jeder Fall-Kontroll-Studie essentielle Bedeutung zu. Die vorliegende Arbeit berichtet nach einer kurzen Übersicht über die bei der Auswahl des Kontrollkollektivs zu beachtenden allgemeinen Prinzipien über die Ergebnisse einer empirischen Bestandsaufnahme zu verschiedenen Aspekten der praktischen Realisation der Kontrollgruppenauswahl...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.