You hear and read about children who are having developmental problems or who are developmentally delayed. But what does that mean?

Children do not develop skills at specific times. Some babies walk as early as 9 months and others not until 15 months. Both of these babies are normal. Short-lived delays are not usually cause to be worried.

Developmental disabilities are different. Kids don’t outgrow or catch up from them even though they may make progress. Attention deficit hyperactivity disorder (ADHD) is one type of developmental disability.

What is called a developmental delay such as ADHD is more than just being slow to develop or a bit behind. A developmental delay means a child is continually behind other kids his age in his development. It means he may be a little behind in several areas of his development. However, it is important to remember that even children with ADHD can be helped.

About 15 percent of children in the United States from ages 3-17 have a developmental disorder. Children diagnosed with attention deficit hyperactivity disorder account for 11 percent of the developmental disorders. The average age of diagnosis of ADHD is 7 years of age.

More than 3 million cases per year of ADHD are diagnosed. We know that treatment can help, but ADHD is a condition that can’t be cured. ADHD usually begins in childhood and frequently persists into adulthood.

Children with ADHD have difficulty sitting still in classrooms. They are the ones who have problems paying attention to what the teacher is saying. Having this problem contributes to low self-esteem, troubled relationships and difficulty at school or work.

ADHD isn’t always easy to diagnose. The symptoms are common problems we all face. We are all forgetful, distracted, restless, overwhelmed and lose track of things. One test for ADHD asks the following questions which paint a vivid picture of the problem for children and adults.

I pay poor attention to detail. I often make small mistakes in my work. I skim read. I tend to rush things. I mess up dates, get numbers wrong or fail to notice typos. I often overlook details in filling out forms or forget to add attachments to emails. I tend to make simple errors because I’m not paying attention.

I am easily distracted. I find it difficult to stick with longer tasks — even leisure activities. I may go off to do something else or I end up doing several things at once. I struggle to follow through on complex tasks. Short deadlines work best for me. I’ve been called a “day-dreamer.”

I am a poor listener. I find I am easily distracted during longer conversations. I tend to tune out. I may be looking right at someone but I’m lost in thought. My mind often wanders. I often miss what’s being said. So I have to ask people to repeat themselves. Sometimes, I even lose track of what I’m saying.

I don’t follow instructions. I prefer to jump right in, rather than read through instructions, guides or recipes. I don’t have regular routines at work or home. I struggle with schedules or plans. I’m not being obstinate. I know what to do, I just can’t seem to do it.

I feel disorganized. I have trouble organizing my work schedule and even my social life. I create long to-do lists then find them overwhelming. Planning a big project feels daunting. I procrastinate because I can’t see where to start or figure out what I need.

I avoid tasks that require sustained mental effort. I struggle to finish things that demand a lot of focus for a long period of time. When faced with a big, important task, I will do a bunch of trivial chores instead. I hate paperwork.

I often lose things I need. I often misplace things like my phone, keys or TV remote. “I just had it a minute ago!” I often lose important paperwork or cannot find something I just bought. My home or workspace is cluttered, piles everywhere. Things have to be out where I can see them, otherwise I worry that I’ll forget about them.

I am forgetful. I often lose track of what I’m supposed to be doing or what I’ve already done. I’ll forget to pack something and have to go back. I’m bad with names. I forget appointments or promises. When I am alone I talk out loud to myself to stay on track. I have sticky-notes everywhere. I’ve bought things and then realized I already owned one.

Now what?

What does all this mean? This isn’t an easy problem to deal with. It means parents with any concerns about their child’s development should seek medical evaluation without delay.

Early intervention can improve outcomes. It also means you need to learn a lot about the problem your child is experiencing. You make a huge difference in how your child is treated, progresses and reacts to having a major developmental problem.

It also means you need to help your child learn to deal with ADHD. It can be around for a lifetime.

Cynthia Martin is the founder of the First Teacher program and former executive director of Parenting Matters Foundation, which publishes newsletters for parents, caregivers and grandparents. Reach Martin at pmf@olypen.com.