Saturday, July 24, 2010

The height of depression?

A number of studies have suggested that a person's height is associated with depression with taller people being less likely to be depressed. This effect, if it exists, could be reactive whereby the individual experiences low self-esteem or perhaps bullying as a result of their low stature. Alternatively short stature could be a marker for poor early life conditions. The evidence seems unclear overall.
So what if anything can we tell from the Growing Up in Ireland data? Below I graph a depression index (for the main carer in the study) against their height, adjusting for age, household income and whether there is a partner in the house. This is not a random sample of the population remember: all of the respondents (i.e. the main carers) have a child in the study (most of whom are 8 years old) & almost all are female i.e. they are typically the mother.
While it may not be obvious there is indeed a slight gradient: taller people do have a lower depression score. The association is small: on average one additional centimetre in height is associated with a reduction in the depression score of .005 (half of one percent) of a standard deviation. So while it is statistically significant, arguably it is not significant otherwise.
To put things in context having a partner in the house has approximately one hundred times the effect of an additional cm in height (i.e. half a standard deviation), so hang onto your man, I guess.

2 comments:

Peter Carney said...

Kevin: Interesting stuff. can you do it for dad's also?


P.S:
http://www.youtube.com/watch?v=VweadeTCvNA&feature=related

Kevin Denny said...

One can look at the "secondary carer" which will usually be the man of the house (Am I allowed say that now?). So yes I think: will have a look at some point.
Well if finding a good man was as easy for a woman as finding a needle in a haystack, how come most of them do? So cheer up Peter, all is not lost.
Actually I had guessed that your link was to something else: Randy Newman's classic "Short people"
http://www.youtube.com/watch?v=uFmv22ghzQw