In Reply.—I appreciate Dr Lubicky's interest in my study of concurrent habits, but he has misunderstood it in two ways. First, it was not a study of thumb-sucking per se, but rather of covariation between chronic thumb-sucking and object attachment (ie, the "Linus" syndrome). To study this covariation, I treated thumb-sucking and measured, but did not treat, attachment. I followed guidelines derived from a thorough literature review for treatment of thumb-sucking.1,2 These guidelines recommend that only children aged 5 years or older be treated to reduce thumb-sucking, and then only if the habit is chronic (ie, occurs in more than one environment, such as at home and at school). Thumb-sucking is common in young children, but chronic thumb-sucking in children aged 5 years and older is not. No incidence figures are available, but my estimate, based on 9 years of research on thumb-sucking, is that about 5% to
FRIMAN PC. Thumb-Sucking-Reply. Am J Dis Child. 1991;145(8):846. doi:10.1001/archpedi.1991.02160080019006
Artificial Intelligence Resource Center
Customize your JAMA Network experience by selecting one or more topics from the list below.