The four cultural areas of the state were divided into 8 zones, each made up of
contiguous counties. The Pearson's mean square contingency coefficient of association
was computed using 127 socioeconomic and cultural indicator variables
(Gregory, 1958). Towns were divided into 3 size classes (250-999; 1000-2499; and
2500-5000); the sub-area clusters equalled 24 (8 × 3). In each sub-area, 2 towns
were selected at random from each of the 2 larger town size categories and 4 from
the smallest category for a total of 64 towns. Households were enumerated from
blocks selected at random. If a household contained one or more person(s) 65 years
of age or older living independently, one person 65 years or older was selected at
random. The number of elders selected in each of the 64 towns was proportional to
their number in the particular social area using the 1960 census. The final sample
of 1700 independently living elderly individuals represents all independently living
Missourians 65 years and older living in towns of 250-5000 in size.