Bedwetting alarm. Proven in numerous respected studies. However, need to be used correctly. 1) child must agree to use of alarm, 2) pep talk, like a sport's coach at bed-time about alarm & parents need to wake child to switch off alarm, if child fails to wake, and take child to bathroom, 3) avoid any blame, 4) give alarm at least 6 weeks of use every night before giving up, 5) continue using 4-6 weeks after success.
Enuresis. With help of your family physician, explore the cause & treat that, such as urinary tract infection, diabetes, or structural abnormalities in urinary tract. Treatment options can include bladder training, moisture alarm, & medications such as ddavp, (desmopressin) & ofcourse, correcting any abnormalities.
Alarm and behavior. Behavioral treatment using a bell and pad alarm is very effective. Here is an article from a former associate and pediatric psychologist now practicing in the columbia s.C. Area: http://cpancf.Com/articles_files/goodnightbedwetting.Asp.