Tuesday, January 8, 2008
The Dreaded Bell Curve
So what exactly is "normal"? The typical Gaussian bell curve (can't believe I even remember that word) shows that middle 95% of what is expected for any given age. So what gets us baby doctors all in a tizzy is that top and bottom 2-3%. So if your kid is in the top 2-3% for weight, stop the sugar and cut the cables to the Wii. That is unless the height is also in the top 2-3% and is proportional AND the kid's parents both happen to be American Gladiators (so glad that show is back on!).
When it comes to development, you never hear anyone complaining that their kid is in the top 2-3% for their milestones. Unless their kid is getting wedgies all the time from the other kids in his class for messing up the curve for everyone else (yeah, that was me; the curve part, not the wedgie part, sucker). When something falls a little outside of what we consider to be "normal". we pull out our handy-dandy developmental charts and papers. These can be found in any decent pediatric tome, including Harriet Lane, Nelson's Pediatrics, etc. Many pediatricians' offices even have their own customized ones with screening questions that are asked at each visit (or at least they should be).
Quite often, the parents will bring it up after Grandma or Aunt Sue or great Uncle Joe make some comment along the lines of, "Shouldn't she be walking/talking/potty-trained/composing sonnets/figuring out a new law of thermodynamics by now?". So we are trained way back in med school on how to remember what happens when. The AAP website has some great age-based guidelines for parents.
I'm going to have to do a primer on development at some point. Most kids should sit (supported) at 6 months, cruise by 9 months and walk at 1 year. By a year we expect a kid to be able to walk or at least stand alone, have 1-2 specific words, be socially interactive and be able to feed himself Cheerios. By 2 years, most kids should be able to kick a ball, go up and down stairs with help, run, scribble, use 2-4 word sentences and start to imitate people. There is more on the AAP website. By the time they're 18 they will know how to never refill the gas in the car, run up your phone bill and make you crazy with all that newfangled music, little whippersnappers (love that word).