Against the background of regional differences in morbidity and social determinants of health small-scale health services research is becoming increasingly relevant, particularly for planners of population-based integrated care models. Despite of longstanding research of regional variation especially by John Wennberg neither are there scientifically or practically accepted standards on how to identify regions which are in a special need for integrating health services nor is there a precisely defined set of methods which could be used to identify and prioritize problems in health services delivery.