They look for national differences in happiness and use blood pressure readings as objective measures of hypertension when making the inter-country comparisons. I have not read the study, only the abstract (parts below), but I measure my BP often and low readings make me very happy.
I also know that readings can be all over the place. And I seldom take a reading when I am busy enjoying work or play. Relative blood pressure readings, anyone?
In Hypertension and Happiness across Nations (NBER Working
Paper No. 12934), co-authors David Blanchflower and Andrew
Oswald draw upon data on 15,000 randomly sampled individuals from 16 countries,
and on other larger samples, to develop a measure of well-being related to the
incidence of high blood pressure. They find evidence to suggest that happier
nations report fewer blood-pressure problems. And, this seems to be true
regardless of the dataset used in the analysis. Nor do the results seem to be
caused by differing numbers of physicians across countries.
The authors' findings in this study rest on three assumptions:
first, that it is reasonable to treat their survey evidence on
high-blood-pressure problems as a proxy for true measures of hypertension.
Second, that people report high blood pressure in a more objective way than they
report levels of happiness. Third, that the patterns they find are not merely
the product of something special for this particular sample of