“group discussion techniques could be employed to change a variety of similarly entrenched behaviors involving health practices and child care. For example, when rural mothers in a maternity hospital were individually advised by a nutritionist to administer cod-liver oil to their newborn infants, only about 20 percent complied within the initial test period. When the same information was introduced in the context of a six person discussion group, the rate of immediate compliance more than doubled, reaching 45 percent.”