In medicine, the BUN-to-creatinine ratio is the ratio of two serum laboratory values, the blood urea nitrogen (BUN) (mg/dL) and serum creatinine (Cr) (mg/dL). Outside the United States, particularly in Canada and Europe, the truncated term urea is used (though it is still the same blood chemical) and the units are different (mmol/L).
Your child must be both physically and emotionally ready for toilet training. Most children are ready to start when they are between 22 and 30 months of age, but every child is different. Toilet training usually becomes a long and frustrating process if you try to start it before your child is ready.
What is the average age for toilet-training? The physical maturity and readiness skills needed for successful toilet learning appear at the same time in girls and boys-between 18 and 30 months of age. The average age for girls to be toilet trained is 29 months, and for boys it's 31 months.Keep in mind that these are averages. Ninety-eight percent of kids are trained by 36 months of age.n average time frame for success in toilet training is three to six months. It is common, however, for children to continue to wet at night until they are five years old. By six years of age, most children (90%) do stay dry all night.