My wife is how old?

When designing applications, I think it's important to put "sanity" checks into the front-end systems. I'll give you an example.

Years ago, I'd taken a new job and enrolled in the medical benefits program. As is common with these programs, they need your social security, and a date of birth to validate membership.

My wife had a prescription to fill, and we were at the pharmacy trying to get it filled, and while I was in the system, my wife was not. The lady behind the counter told me that we needed to go back to HR to figure out what was wrong. But, after a phone call with the provider, and some more sleuthing on the cashier's part, she finally figured out what had happened. Apparently, when I had entered the form for my wife, my "7" looked like a "9" and they misread my wife's birth date as "1991" instead of "1971". Since this was somewhere around the year 2000, that would have meant my wife was nine years old. I'm pretty sure even Arkansas doesn't allow that to happen.

That's a perfect example of a data quality sanity check. When the person keying that information in entered it, the system could have *beeped* and prompted a message that said "This spouse is less than 16 years old (16 is probably a reasonable cut off for the age of a spouse), is that correct? And the entry clerk could have taken a second look at the form, instead of just blindly entering it in, and probably would have stopped, fixed the issue, and then went on. Data quality problem avoided.

On a related note, I had a friend in high school who married a 13 year old girl. They had to do it in Oklahoma, since Arkansas (where I lived at the time) wouldn't allow it. Crazy.