H—3l

Fig. III. —Distribution of Test Areas: Control Areas (Not Marked) were all North of the Waitemata Harbour-"North Shore."

The distribution of the test areas is shown in the sketch map (Fig. III). It was agreed between members of the team* that in all eases they would try to gain admittance to the house, and sit down quietly in the living-room with the housewife, before commencing detailed inquiries ; information gained on the doorstep could not be of equal value. They were instructed to use some such formula as : "I am Dr. of the Health Department. We are making some inquiries in connection with the infantile paralysis outbreak. We are trying to find out how much illness there is in Auckland at present. I mean illness of any kind, including quite minor illnesses. Do you mind giving me some particulars ? " Instructions to the investigator continued as follows : " Information must be extracted by direct and persistent questioning. If necessary, give reassurance that it is not intended to apply any restrictions as a result of this investigation. Do not accept a reply that a person has not been ill lately without further probing.

* The bulk of this part of the investigation was carried out by Dr. G. A. de Lautour and Miss D. F. Gatenby.

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