Can parents do a throat culture?

Throat swabs for Group A beta-hemolytic Streptococcus were obtained from 98 patients, ages 4 to 17 years, both by their parents and by physician investigators. Compared with results obtained by physicians, there was a false negative rate of 32% (P less than 0.001) for the parents. The discrepancy was greater in the youngest age group (38% false negative rate in the 4- to 8-year-olds) compared with older children (P less than 0.001). The overall sensitivity and negative predictive value for the parent-obtained swabs were 68 and 45%, respectively. In the 4- to 8-year-old group, these values were 62 and 37%, respectively. Because there were no false positives the positive predictive value was 100%. We conclude that the false negative rate for untrained parents obtaining throat swabs is too high to warrant the implementation of home testing for Group A streptococci.