Monday, October 10, 2011

Prayer can reduce depression: some econometric evidence

There has been a lot of work in recent years by economists on the determinants of people’s well-being. Many of these determinants are not something you can do much about at least in the short run, like income or health.

In a paper in press in Social Science and Medicine I look at the effect of prayer on the number of symptoms of depression recorded by individuals in the previous month. The data is from the Survey of Health, Aging and Retirement in Europe (SHARE) . I use the Euro-D scale which was designed to measure the incidence of depression symptons in an older population – it is not a diagnostic scale.

There are many studies looking at associations between well-being or mental health and either religion affiliation or devotion. Freud took a rather dim view of religion and this has cast a long shadow on the issue. As far as I can see, he did not do any serious data analysis so its unclear to me why one should put any weight on his views.

A problem of course in this literature, is whether one can infer anything causal. After all, people who are feeling down might easily turn to religion as a response. I use instrumental variable estimation to tackle this issue.

This turns a positive association (prayer positively correlated with depression) to a negative one i.e. prayer reduces the number of depression symptoms. This is not that surprising in a sense: if prayer made you more miserable on average, you would have an incentive not to do it. The results are robust to various combinations of instruments.

The magnitude of the effect (of praying at least daily) is comparable to that associated with different marital statuses, about half that of being female and twice as big as the effect of being unemployed.

I speculate on the possible mechanisms behind this effect, noting that it may not be the religious aspect per se. There is increasing evidence of the benefits of meditition and mindfulness based techniques for reducing depression and anxiety.


Liam Delaney said...

One of the first papers on the effects of prayer is one by Galton. It is a really nice piece, not unlike something you would see, with more sophisticated maths albeit, in the JPE.

Its a really ingenious paper for lots of reasons, using advanced causal reasoning and one of the first use of insurance prices in a model of this kind/

Kevin Denny said...

Didn't Galton also look at whether shipwrecks & whether those with clergy on board (hence with more prayers ) were less likely to sink?

Liam Delaney said...

Yep - below is from the paper linked

"Again, there is a large class of instances where an enterprise on behalf of pious people is executed by the agency of the profane. Do such enterprises prosper beyond the average? For instance, a vessel on a missionary errand is navigated by ordinary seamen. A fleet, followed by the prayers of the English nation, carries reinforcements to quell an Indian mutiny. We do not care to ask whether the result of these prayers is to obtain favourable winds, hut simply whether they ensue in a propitious voyage, whatever may have been the agencies by which that result was obtained. The success of voyages might be due to many other agencies than the suspension of the physical laws that control the winds and currents; just as we showed that a rapid recovery from illness might be due to other causes than direct interference with cosmic order. It might have been put into the captain’s heart to navigate in that course and to perform those acts of seamanship which proved links in a chain that led to eventual success. A very small matter would suffice to make a great difference in the end. A vessel navigated by a man who was a good forecaster of weather and an accomplished hydrographer would considerably outstrip another that was deficient in so accomplished a commander, but otherwise similarly {p.133} equipped. The perfectly instructed navigator would deviate from the most direct course by perhaps some mere trifle, first here, then there, order to bring his vessel within favouring slants of wind and advantageous currents. A ship commanded by a captain and steered by a sailors whose hearts were miraculously acted oupon in answer to prayer would unconsciously, as by instinct, or even as it were by mistake, perform these deviations from routine, which would lead to ultimate success.

The missionaries who are the most earnestly prayed for are usually those who sail on routes where there is little traffic, and therefore where there is more opportunity for the effects of secret providential overruling to display themselves than who sail in ordinary sea voyages. In the usual sea routes a great deal is known of the peculiarities of the seasons and currents, and of the whereabouts of hidden dangers of all kinds; their average risk is small, and the insurance is low. But when vessels are bound to ports like those sought by the missionaries the case is different. The risk that at attends their voyages is largely increased, and the insurance proportionately raised. But is the risk equally increased in respect missionary vessels and to those of traders and of slave-dealers? The comparison between the fortune that attends prayerful and non-prayerful people may here be most happily made. The missionaries are eminently among the former category, and the slave-dealers and the traders we speak of in the other. Traders in the unhealthy and barbarous regions to which we refer are notoriously the most godless and reckless (on the broad average) of any of their set. We have, unfortunately, little knowledge of the sea risks of slavers, because the rates of their insurance involve the risk of capture. There is, however, a universal testimony, in the parliamentary reports on slavery, to the excellent and skilful manner in which these vessels are sailed and navigated, which is a reason for believing their sea risks to be small. As to the relative risks run by ordinary traders and missionary vessels, the insurance offices absolutely ignore the slightest difference between them. They look to the class of the vessel, and to the station to which she is bound, and to nothing else. The notion that a missionary or other pious enterprise carries any immunity from danger has never been entertained by insurance companies."