However, there was also a difference in the social strata of women remaining in the study between the test and control groups. The retention rate in the test group was higher among women with the lowest levels of education, while
the reverse was the case in the control group. This may well be a reflection of the mothers’ varying motivation to participate in the study. Mothers with the lowest formal education level may see participation in the test group as an opportunity to extend their knowledge about the prevention of ECC and thus improve their parenting skills. Mothers with the highest education may feel less need for this support. In contrast, mothers with lower educational attainment in the control group may not identify with the value of the research and be unwilling to continue to participate. The same pattern was seen when retention was correlated to family income.