Quality assurance 1: the survey to clarify discrepancies
A major purpose of the 2011 Census is to determine the exact number of inhabitants in Germany on 9 May 2011. The basis used here is the data of the population registers. As, however, those data were not always correct, discrepancies occurred – as had been expected – when the population register data were combined with the results of the census of buildings and housing.
For municipalities with less than 10,000 inhabitants, the discrepancies were easily eliminated through the survey to clarify discrepancies. This is because, as experience has shown and as has been confirmed by the census test, the population register quality in small municipalities is better than in large ones. Therefore it was sufficient in small municipalities to conduct the survey to clarify discrepancies in addition to the survey to clarify the residence in order to determine the number of inhabitants.
To clarify the discrepancies, relevant addresses were selected and the people living there were questioned using a reduced questionnaire (PDF, 865KB, file not barrier free). As a rule, the survey was conducted at addresses with just one occupied dwelling and only in municipalities with less than 10,000 inhabitants.