Is there any way to reliably assess a person's age?

February 6, 2007 5:09 AM

Is there any way to reliably assess a person's age, and if so, to what precision?

That is, with no details other than what can be gained from medical tests including autopsy, is it possible to tell how long a human subject has been alive for? (apparently DNA's out)

posted by teem to health & fitness (16 comments total)

I know that as we age, the coccyx bone (due to carrying our weight) changes from a differentiated series of bones into a fused segment as the cartilage ossifies. That gives you a ball-park figure.
posted by RavinDave at 5:21 AM on February 6, 2007

Teeth can be used.
posted by JJ86 at 5:29 AM on February 6, 2007

According to this paper: " Age estimation of unaccompanied minors", Forensic Science International, Volume 159, Pages S61-S64
A. Schmeling, W. Reisinger, G. Geserick, A. Olze

A combination of tests that involve examining the development of the sex organs, cartilage growth in the hands and the clavicle, and dental examinations, can supposedly be used to determine age with a margin of error of 12 months.

However, the authors also say "...for age diagnoses obtained with a combination of methods there is still no satisfactory way to scientifically determine the margin of error.

Also, this paper focuses on minors, I am sure these methods lose accuracy the older the person is.

The paper also makes note of the fact that ethnicity and socia-economic background can skew the results of the tests mentioned above.
posted by toftflin at 5:31 AM on February 6, 2007

I'll take a general stab, saying yes, there are ways to determine the age of a body - to an extent.

The physical appearance and examination is the primary source of information. Beyond that it might require a profile of tests: direct examination at p.m. of organs and blood vessels will contribute and I would think the major pathology test will be bone and teeth studies - densitometry and comparison to known charts. Beyond that I think you will find that there are a quite a few tests that are more at the experimental/research end of the spectrum about which I have no clue.

The extent of the profile available (how much corpse exists and when/what tests and examinations are carried out) will determine the accuracy. But it won't be foolproof. Between biological variations and environmental factors (addictions/lifestyle etc) I imagine even with optimum conditions that there will be a +/- 5% margin of error. [all just my semi informed opinion of course]
posted by peacay at 5:33 AM on February 6, 2007

(From my undergraduate biological anthropology courses:) There are a lot of ways to tell the approximate age of someone up to about 22: teeth, which grow in at different times; certain parts of the joints, which turn from cartilage to bone as we age; and places where bones articulate that can fuse as we age (such as certain parts of the skull).

It becomes much more difficult as we stop growing. At that point, you have to base things on deterioration, which can be affected by a lot of factors. Obviously growing can be influenced by lots of factors, but growing goes through predictable stages, so basically you assess how many the body has gone through to determine the age. Deterioration doesn't go through predictable stages: many people get arthritis, but not everybody, etc.
posted by carmen at 5:45 AM on February 6, 2007

Check their wallet?

I would imagine it depends heavily upon what state the body was in when it was found. A body that is less than a few hours dead from a heart attack is going to have a lower margin of error than some bones dug up in a forest. As others have said, part of the problem is that the condition of the person before death can make the issue far more difficult.
posted by KirTakat at 6:07 AM on February 6, 2007

Token ex-archaeologist here. I'm rusty, so this might not be completely useful.

Being an archaeologist, I never got deal with flesh and blood (yuk!), but I did get to play with lots of skeletons...

On Preiview: what Carmen said...

It is based on the assumption that everyone develops at about the same rate in the same way. Which we don't. So there will always be a margin of error.

The more bits of the body you have the better, because you can assess more variables. So teeth, skull and long bones are useful.

Some people have looked at specifics, such as looking for signs of osteoporosis in older female skeletons - but again, this will vary according to the individual.

To sum up, yes, it's possible to a degree and the more of the body you have, the more accurate you can be.

Anecdotally, there aren't that many reliable methods. My mum works a lot with people who came to the UK during the partition in India. Many lost their personal records, and when they arrived in the UK they were given an arbitrary birth date (usually 1st January) in the year they thought (or the year the officials thought) they were born. If the government has decided that you are younger than you claim to be, it's hard to prove otherwise.
posted by Helga-woo at 6:18 AM on February 6, 2007

On preview I can't spell.
posted by Helga-woo at 6:19 AM on February 6, 2007

Very unscientific and really only works on live people:

I've always been uncannily good at guessing peoples ages. The giveaway? Look at their hands. People do a lot of things to look younger, but their hands always give them away.
posted by Benny Andajetz at 6:25 AM on February 6, 2007

The answer is no - there is no current medical technique which can give an accurate age.

Currently, the most commonly used method for determining an individual’s age at death is to look for signs of wear in the individual’s teeth or in the skeleton. In adults, however, this method is only accurate to within 5-10 years.

There are variety of other techniques which are in various stages of research - the teeth technique mentioned by JJ86 and also Kodak has done some research into whether the red-eye effect you get when taking photos can reveal your age as well.

One interesting new technique is the measure the amount of C-14 (carbon) in your teeth. During childhood, the enamel forms at different times depending on the tooth and is laid down only once. The final formation of enamel occurs at age 12 in a child’s wisdom teeth. This means that the C14 concentration found in the enamel of the tooth reflects the amount of C14 that was in the atmosphere when the enamel formed. By comparing the carbon in the teeth to the recorded levels of carbon in the atmosphere over the last century, a person's age can be determined.

Note however that this technique is still being researched although the signs are promising.

Finally, I believe KirTakat's answer is incorrect IMHO. The issue of the state of the body is more relevant to establish 'time of death', not the age of the body.
posted by tobtoh at 6:37 AM on February 6, 2007

IAAA*. Skeletally, I'd have to say that studying a combination of:

1. dental eruption

2. dental wear

3. epiphyseal fusion (growth plates on long bones)

4. skeletal suture fusion

5. pathological factors, like arthritis, particularly as related to surrounding individuals

will give a good estimate of age. While it's practically impossible to calculate margins of error, for individuals up to the late teens/early twenties, this can give ages to within a quarter or half year (i.e. accurate and precise). Each of the factors has a certain age range associated with it, and layering them all on top of each other is pretty accurate. For adults, the epiphyses are fused and the teeth are all erupted, so you're limited to three factors to consider, all of which are considerably more variable than the other two. Still, skeletal suture fusion can give ages within five or ten years, and combining that with dental wear and pathological factors can give an accurate (but not precise) age. Having a comparative sample that had a similar lifestyle, living area, time period increases the accuracy and precision. Looking at comparative individuals with similar dental care and diet, for example, gives a better baseline than, say, a sample of Russian prisoners vs. paleoindians.

*IAAA = I Am An Archaeologist
posted by The Michael The at 7:20 AM on February 6, 2007

I agree with Benny Andajetz, if it's a live person you can try to guess using their hands. Sadly it's very imprecise.
posted by Memo at 8:42 AM on February 6, 2007

I've noticed the hands thing too. I look like I'm in my early 30's but my hands look my real age (early 40's). I have a friend who's in her early 50's, looks 40ish, but her hands look her real age too.
posted by matildaben at 10:08 AM on February 6, 2007

People do a lot of things to look younger, but their hands always give them away.
Derail: this isn't going to work if everyone gets smart and starts using 40/45 sunscreen on the back of their hands every day, like I do. :) Hey, when you don't wear makeup, you gotta do what you can. So I guess this is why I have had my age misjudged many times.
posted by Listener at 10:59 AM on February 6, 2007

If you're up for a book, I recommed William Bass' Death's Acre: Inside the Legendary Forensic Lab the Body Farm Where the Dead Do Tell Tales.

William Bass started the Body Farm at the University of Tennessee Medical Center. In the book, he tells stories of different cases in his career where he often had to identify a person from just bones, and determining the age was obviously of vital importance. It's a great read and very informative about the different ways to determine age with only minimal remains.
posted by chiababe at 12:57 PM on February 6, 2007 [1 favorite]

[please leave HURF DURF COUNT THE RINGS comments out of here - your answer isn't unique and zingy, it's just been removed three times already]
posted by jessamyn at 2:46 PM on February 6, 2007