We aimed to determine the ideal age for initiating toilet training and investigate the factors influencing the training.

The study population comprised 1,370 children aged 2-6 years, who visited the pediatric clinics in Jeonju, Iksan, and Gunsan. Their parents were given questionnaires in order to gather data about the types of diapers used, ages when toilet training was initiated and completed for each day and night, its adverse effects, and the educational level and employment and economic status of the mothers.

The toilet training initiation age was low for those living in the country, having an elder sibling(s), and using cloth diapers, and for those whose mothers were employed and had a low economic status. The training completion age was 22.9 months when the training was initiated before the age of 18 months; this was lower than the training completion ages of 25.9 and 31.0 months when the training was initiated at the age of 18-24 months and after 25 months, respectively. However, the required durations in these cases were 8.4, 5.6, and 3.8 months, respectively. Encopresis and refusal occurred more often when the training was initiated before the age of 18 months than when initiated after this age.

Toilet training should begin at least after the age of 18 months considering the developmental status of infants. It is recommended for the future researchers to develop specific guidelines regarding toilet training.