The Economics of HIV/AIDS in Low-Income Countries: The Case for Prevention

The Economics of HIV/AIDS in Low-Income Countries: The Case for Prevention

David Canning

Journal of Economic Perspectives, 2006, 20(3): 121–142.
DOI:10.1257/jep.20.3.121


Abstract
There are two approaches to reducing the burden of sickness and death associated with the human immunodeficiency virus (HIV), which leads to acquired immunodeficiency syndrome (AIDS): treatment and prevention. Despite large international aid flows for HIV/AIDS, the needs for prevention and treatment in low- and middle-income countries outstrip the resources available. Thus, it becomes necessary to set priorities. With limited resources, should the focus of efforts to combat HIV/AIDS be on prevention or treatment? I discuss the range of prevention and treatment alternatives and examine their cost effectiveness. I consider various arguments that have been raised against the use of cost-effectiveness analysis in setting public policy priorities for the response to HIV/AIDS in developing countries. I conclude that promoting AIDS treatment using antiretrovirals in resource-constrained countries comes at a huge cost in terms of avoidable deaths that could be prevented through interventions that would substantially lower the scale of the epidemic.

http://www.aeaweb.org/articles.php?doi=10.1257/jep.20.3.121

Modern Medicine and the Twentieth Century Decline in Mortality: Evidence on the Impact of Sulfa Drugs

Modern Medicine and the Twentieth Century Decline in Mortality: Evidence on the Impact of Sulfa Drugs

Seema Jayachandran, Adriana Lleras-Muney, and Kimberly V. Smith

American Economic Journal: Applied Economics 2 (April 2010): 118–146

Abstract

This paper studies the contribution of sulfa drugs, a groundbreaking medical innovation in the 1930s, to declines in US mortality. For several infectious diseases, sulfa drugs represented the first effective treatment. Using time-series and difference-in-differences methods, we find that sulfa drugs led to a 24 to 36 percent decline in maternal mortality, 17 to 32 percent decline in pneumonia mortality, and 52 to 65 percent decline in scarlet fever mortality between 1937 and 1943. Altogether, sulfa drugs reduced mortality by 2 to 3 percent and increased life expectancy by 0.4 to 0.7 years. We also find that sulfa drugs benefited whites more than blacks. 

(JEL I12, L65, N32, N72)

http://pubs.aeaweb.org/doi/pdfplus/10.1257/app.2.2.118

Ungated version:

http://www.econ.ucla.edu/alleras/research/papers/sulfa_final.pdf

Public health and economics: a marriage of necessity

Public health and economics: a marriage of necessity

Alan Maynard

The Journal of Public Health Research, Vol 1, No 1 (2012)

Abstract

With resources always scarce limited resources have to be targeted at those interventions, prevention and cure, that give the greatest population health gain at least cost. Mere identification of what works in prevention is inadequate unless this evidence is supplemented with economic analysis that identifies what is cost effective. Public health without the use of economics is incomplete.

http://www.jphres.org/index.php/jphres/article/download/jphr.2012.e4/pdf

Four Decades of Health Economics Through a Bibliometric Lens

Four Decades of Health Economics Through a Bibliometric Lens
Adam Wagstaffa, Anthony J. Culyerb
Journal of Health Economics, Forthcoming

Abstract

In this paper, we take a bibliometric tour of the last forty years of health economics using bibliographic “metadata” from EconLit supplemented by citation data from Google Scholar and our own topical classifications. We report the growth of health economics (we find 33,000 publications since 1969—12,000 more than in the economics of education) and list the 300 most-cited publications broken down by topic. We report the changing topical and geographic focus of health economics (the topics ‘Determinants of health and ill-health’ and ‘Health statistics and econometrics’ both show an upward trend, and the field has expanded appreciably into the developing world). We also compare authors, countries, institutions and journals in terms of the volume of publications and their influence as measured through various citation-based indices (Grossman, the US, Harvard and the JHE emerge close to or at the top on a variety of measures).
JEL classification B20;I10
Keywords Health economics; bibliometrics; history of economic thought

Ungated Version

The Economics of Tobacco: The Market for Cigarettes in Ireland

A recent report from the Revenue Commissioners Research and Analytics Branch examines "The Economics of Tobacco: Modelling the Market for Cigarettes in Ireland" (Padraic Reidy and Keith Walsh; February 2011). Highlights from the executive summary are below.

"Numerous explanatory variables of cigarette consumption are explored but the only factors that are found to be statistically significant in the most efficient econometric regression are: price, income, the introduction of the smoking ban, EU enlargement and the point of sale advertising ban. Of these, the most important effect is from price.

The model suggests a price elasticity of -3.6, i.e., a 1 per cent increase in price results in a 3.6 per cent reduction in cigarette consumption. This price elasticity is extremely high compared to other estimates for the Irish market, most suggest a figure of between 0.5 and 1. A price elasticity of -3.6 is too high to be realistic, for example it would imply that a 10 per cent increase in price reduces smoking by 36 per cent... Therefore another factor must be at play.

...The price elasticity estimated refers to taxed cigarettes: a 1 per cent increase in price leads to a 3.6 decrease in consumption of taxed cigarettes. The most reasonable theory to explain such a large decrease in taxed consumption is that only part of the reduction is caused by lower smoking levels, the remainder must be caused by smokers switching to substitute cigarettes. The most likely substitutes in the case of taxed cigarettes are non-Irish taxed cigarettes...

...Revenue estimates that currently around 20 per cent of cigarettes consumed in Ireland are not Irish taxed and this figure has been increasing in recent years... Further analysis finds some evidence that cigarette tax levels have moved beyond a critical point at which increases in tax rates lead to lower, rather than higher, tax revenue. Further tax (price) rises will reduce smoking somewhat but they will also greatly encourage more untaxed consumption.

Increasing the taxation of cigarettes in Ireland no longer carries the combined benefits of better public health and higher revenue for the public finances... This suggests that taxation increases are no longer the optimum tool for reducing smoking in Ireland. This is further supported by the significance in the model results of the effect of the smoking ban. Such non-price measures are shown to reduce taxed consumption and do not carry the same incentive to switch to untaxed cigarettes as higher rates of taxation."

Going to America

Best wishes to Liam for his impending research visit to the Center for Health and Wellbeing at Princeton University. See you back here at the end of the summer Liam; and looking forward to discussing research with you on this blog in the meantime.

Do Higher Grades Mean Better Health?

The relationship between education and health has been discussed several times on this blog, most recently by Kevin. Kevin mentioned that there is a positive socioeconomic gradient: more educated people have better health on average. However, this does not imply that one causes the other. Kevin also mentioned recent research by Nils Braakmann, which examines the relationship between education and health, exploiting exogenous variation from a compulsory schooling law in the UK. Braakmann's results indicate "neither an effect of education on various health related measures nor an effect on health related behaviour, e.g., smoking, drinking or eating various types of food."

An interesting way of moving this research topic forward could be to focus more on quality of education rather than quantity of education. While there are many ways to consider how best to measure quality, one outcome that differentiates between students is grade point average, or grades. This metric has been the source of much debate (some of which I mentioned yesterday), but there is already some research which has set about examining the relationship between grades and health. (As an aside, readers may be interested to know that there is a positive relationship between college grades and subsequent earnings, as reported by McIntosh (2006), Loury and Garman (1995), Jones and Jackson (1990), Filer (1983) and Wise (1975).)

The research examining the relationship between grades and health came to my attention via an article by Roni Caryn Rabin in the Health section of the New York Times. The article refers to research done by Dr. Pamela Herd, and her colleagues at the University of Wisconsin in Madison. The research uses the Wisconsin Longitudinal Study, which has been following more than 10,000 people who graduated from Wisconsin high schools in 1957. "Those students who finished in the top 25 percent of their high school class were healthier, decades later, than the ones who finished in the bottom quarter... Even among those who each had 12 years of education, the person who performed better had better health".

Dr. Herd considered the possibility that better non-cognitive ability (or certain personality traits) could be driving both academic performance and health behaviour. NYT journalist Rabin provides more detail on Dr. Herd's thoughts on the matter:

"One explanation is that the same psychological characteristics that make for a hardworking student — like conscientiousness, dependability, good study habits and following the rules — also shape healthy behaviors. But when Dr. Herd examined personality surveys the graduates of 1957 filled out, controlling for variables like family background and childhood health, she didn’t find a strong correlation with health status... She’s convinced there’s something about the actual mastering of academic material that’s vital... the process of developing critical thinking skills and improving cognitive function."

Irish Fiscal Position and Public Health

A few of the public health students were interested in the current Irish economic situation. I will use this post to give a brief update about the situation aimed at non-economists and describe where you can get sources to read and monitor the situation. The overall fiscal situation is important as it sets the context in which health policies are proposed and evaluated.

1. Irish Economic Situation

From 1994 to 2001, Ireland had one of the world's fastest growing economies, fuelled by a uniquely positive confluence of demographic and environmental factors. Growth slowed from 2001-2007, but during this time Ireland still recorded impressive levels of growth compared to other advanced industrialised economies. Since 2007, we have had one of the largest falls in national income of any country in the world, with only Latvia experiencing a greater percentage decline during this period. One major theory of the cause of this collapse is the over-reliance on property speculation in the Irish economy, particularly from 2004 onwards. This had a number of adverse effects - it left homeowners very exposed both in terms of their income and wealth to a property shock, it diverted resources away from potentially more productive areas of the economy, it artificially inflated the government revenue figures and it left bank balance sheets overexposed to property development loans. Anglo Irish Bank, in particularly, conducted massive amounts of lending on interbank markets and effectively ploughed this into the domestic construction industry. Following the collapse of Lehman brothers bank in the US, Ireland was left extremely exposed in the ensuing market uncertainty. In 2008, Irish banks were finding it increasingly difficult to borrow on international markets and speculation heightened that Anglo and perhaps even the two main retail Banks AIB and Bank of Ireland might go bust. In late 2008 the finance minister guaranteed the liabilities of all the Irish banks. This included deposits but also bonds. Following this, an asset management programme (NAMA) was introduced to buy bad property loans from the banks. These loans, most of which are impaired, are effectively bought at a big discount and taken off the balance sheets of the banks to make the banks less risky to potential investors. However this process exposes the taxpayer to a lot of risk and also means that the banks have to admit the full extent of the losses. Following this, the government then had to purchase stakes in the banks to ensure that they had sufficient capital. Nobody knows ultimately how much all of this is going to cost - figures range from 40 billion to 70 billion depending on who you read. This, combined with a drastic reduction in tax revenue, has dramatically increased our debt relative to income ratio. As of last week, the international financial markets have more or less given up on Ireland with Irish state borrowing costs consistently in excess of 8 per cent, meaning that lenders have a strong belief that Ireland simply wont be able to pay all of this back. The prognosis for the next ten years is very uncertain. The view of "moderates" such as Professor John McHale of NUIG is that determined fiscal action such as passing the upcoming budget will enable us to bring the costs of borrowing down to reasonable levels (see link below). People like UCD's Morgan Kelly and independent analyst Constantin Gurdgiev have taken the view that the cost of the banking bailout coupled with the fiscal deficit has simply become too high and that the state is effectively bankrupt and will require an intervention either by the European Commission or the IMF. In such an event, Ireland would receive enough money to meet its public spending at interest rates lower than the market rates but would be forced into dramatic public spending reductions in return.

http://www.irishexaminer.com/ireland/is-irelands-number-up-136365.html

http://www.irishtimes.com/newspaper/opinion/2010/1108/1224282865400.html


2. Implications for Public Health Spending and Employment

The Irish healthcare system is financed partly by private health insurance but mostly by taxation. The Department of Health receives its budget from the Department of Finance and is responsible for the direction of healthcare policy, with policy implementation being the domain of the Health Services executive. The HSE has a budget of approximately 10 billion. The massive decrease in exchequer revenue coupled with the dramatic rises in the cost of servicing borrowing will mean big decreases in the amount of finance made available to the public health system. Some implications for healthcare that are worth discussing include:

a. There will be marked changes in work practices in the publicly funded health system. The "Croke Agreement" linked below outlines some of the principles underlying the basic agreement, which agrees to keep public sector pay levels constant in return for reforms to work practices.

http://www.impact.ie/iopen24/pub/crisis/agreement/payagreedoc.pdf

b. There will likely be cuts in publicly funded health services, particularly on the non-pay side. The report for the Department of Finance by Colm McCarthy (Bord Snip) details priorities for cutbacks in health expenditures. See 3.11 of the report attached. Some of the likely areas will include rationalisation of administrative structures, declines in welfare entitlements, reduction of staff numbers through "natural wastage", reduction in use of external agency staff and so on.

www.finance.gov.ie/documents/pressreleases/2009/bl100vol1.pdf

c. Cost-effectiveness will likely become an increasing concern for the development of health services as the available funds become less and the demands on them greater.

d. Due to the political implications of the downturn, the next government is likely to be headed by Fine Gael. They have proposed (see below) to abolish the HSE and replace it with a disaggregated hospital trust model.

http://www.finegael.ie/news/a/4326/article


3. Some potential action points for public health practitioners

It is always important for ethical public health practitioners to demand that public money be spent toward effectively improving people's health. The nature of the debate does become somewhat more urgent though during a major economic downturn. Some talking points are below, and I happy to field questions if people want to practice some arguments.

a. The importance of ensuring that programmes with major long-term benefits are not disproportionately affected. A very lazy way of making cuts is simply to cut things that do not have short-run impacts. It is important that people with scientific knowledge of the long-run effects of areas such as childhood screening programmes, interventions with disadvantaged young mothers and so on make the case strongly.

b. The insistence on an embargo on the recruitment of new staff into the public health service is something that should be examined.

c. The nature of recession will change the demands on the public health system, particularly in areas such as the provision of mental health services.

d. The need to argue the case for public health spending will become more pressing, particular in areas such as child nutrition, screening programmes and so on.

e. Public health scientists should be active in promoting an effectiveness-driven approach to healthcare allocation and attempt to counteract the "parish-pump" tendencies of a lot of Irish healthcare policy.

f. Many public health practitioners explicitly place "equity" or concern for fairness at the heart of their practice. This will be increasingly important in the context of long-term unemployment and regional declines engendered by the recession.

Sources:

Many of the country's top academic economics post to a website called www.irisheconomy.ie. This is, in my opinion, the consistently best website for getting informed opinions on the Irish economic situation.

Detailed statistics on the Irish Economy, including employment numbers, are available on the cso website www.cso.ie

The Department of Finance website contains detailed figures and updates on our fiscal position. The estimates of public expenditure, below, give a breakdown of where the health budget is spent.

http://www.finance.gov.ie/

http://www.finance.gov.ie/ViewDoc.asp?DocId=-1&CatID=13&m=f

The OECD health website provides substantial data on relative health spending and healthcare inflation, among other things - http://www.oecd.org/health/healthdata

sick to the teeth...

You may recall a blog post a few months back on dental services in Ireland. Essentially, I pointed out that a staggering 399,262 more treatments were provided by dentists to medical card patients in Ireland during 2009. That was a full 34% more treatments carried out than was projected by the HSE based on year-on-year trends since the scheme's inception in 1994. It is true that there were more medical card holders in 2009, but only 4% more. I strongly suggested that it is completely infeasible for this extra 4% of people to have induced 34% more demand in the system and that the alternative possibility -- a 30% decline in dental health in one year -- is equally ludicrous. The figures are strongly suggestive of the phenomena of supplier induced demand. The phenomena is well documented in the international health economics literature and often arises with "free" schemes essentially because 'the supplier of the service is also the demander' (..due to the inherent information asymmetry in the health care environment that requires a trust relationship between the health professional and their patient).

The HSE, faced with these 'inexplicable' increases and substantial narrowing of their overall budget during 2010, decided to cap the amount payable for the scheme to the pre-2009 level; the amount paid before the incredible 34% increase in dental services. The immediate response of the Irish Dental Assoc. was to claim that their members would now only be able to offer emergency services and oral examinations. I have heard no update on this position since.

So what is new??

In June, two dentists brought a case to the High Court to seek an injunction against the HSE implementing the spending cap. The claimed that the measures were a breach of contract, and would have "disastrous consequences" for them as dentists and "a dramatic effect on public health". The were successful, and won an injunction against the HSE preventing them from implementing the spending cap.

The CEO of the Irish Dental Assoc. welcomed the decision saying that he had "huge concerns for the dental health of the country". He described the HSE's move as "unsafe, unworkable, and unethical" and further went on to say that "it would hit the most vulnerable in our society hardest". The HSE subsequently appealed to the Supreme Court against the High Court injunction, but a 'stay' was placed on the High Court's injunction. So, from what I can decipher, a full hearing will now go ahead later this year (most likely early October)

The story looks like it will continue for some time. I can't help but wonder, however, if the case for supplier induced demand might be worth a hearing? I've heard nothing about it so far (apart from comments here) and I certainly think it is an issue worth considering in this case. At the very least, the Irish Dental Assoc. could be asked to explain the 34% increase in their services during 2009.

The effects on mortality of nurses striking

The health sector in Ireland has experienced a fair amount of industrial strife in recent years with nurses in particular taking industrial action over pay and other issues. Understandably this generates a lot of anxiety amongst the public or at least those directly or indirectly affected by this. So it is interesting to know whether such industrial action has any consequences for the health of patients. The paper below finds that it does have negative effects & fairly sizable ones at that. This underlines the importance of avoiding these break-downs in normal industrial relations.
Do strikes kill? evidence from New York state
J Gruber, S A Kleiner

Concerns over the impacts of hospital strikes on patient welfare led to substantial delay in the ability of hospitals to unionize. Once allowed, hospitals unionized rapidly and now represent one of the largest union sectors of the U.S. economy. Were the original fears of harmful hospital strikes realized as a result? In this paper we analyze the effects of nurses’ strikes in hospitals on patient outcomes. We utilize a unique dataset collected on nurses’ strikes over the 1984 to 2004 period in New York State, and match these strikes to a restricted use hospital discharge database which provides information on treatment intensity, patient mortality and hospital readmission. Controlling for hospital specific heterogeneity, patient demographics and disease severity, the results show that nurses’ strikes increase in-hospital mortality by 19.4% and 30-day readmission by 6.5% for patients admitted during a strike, with little change in patient demographics, disease severity or treatment intensity. This study provides some of the first analytical evidence on the effects of health care strikes on patients, and suggests that hospitals functioning during nurses’ strikes are doing so at a lower quality of patient care.
NBER Working Paper No. 15855 (March 2010)
http://www.nber.org/papers/w15855

Employment and the flu

The relationship between labour market conditions and health has featured on this blog several times. This paper shows how increased employment increases incidence of the flu presumably through contagion:more infected people interacting with others.

Are pink slips better than flu shots? The effects of employment on influenza rates
S Markowitz, E Nesson, J Robinson
...In this paper, we examine whether increases in labor market activities are associated with an increased incidence of the flu. Flu data come from the Centers for Disease Control. We check the robustness of our results using unique data from Google Flu Trends. Using a first-difference two stage least squares estimation approach, we find that a one percentage point increase in the employment rate increases the number of influenza related doctor visits by about 8.1 additional flu-related doctor visits per 1000 doctor visits for all causes. To put this in perspective, on average, 33 additional people out of every 100,000 new employees will have a flu-related doctor visit. The results are robust across several specifications.

http://www.nber.org/papers/w15796

HESG Summer Conference

The Health Economists´ Study Group  is a UK organisation for people working in Health Economics. However, the group's summer conference is being hosted by University College Cork this summer. The first time, to my knowledge, it's been held in Ireland. The 'study' nature of the group encourages participation by PhD students, i.e., preference will be given to work-in-progress and PhD students and all Health Economics topics will be considered.

Location: Jury´s Cork Hotel, Cork, Ireland

Dates: 23-25 June 2010

Deadline for Abstract Submission: 9th April 2010

Deadline for Early Registration: 11th May 2010

Please send a title and abstract of up to 250 words of the proposed content by 9th April 2010 5pm if you wish to have a paper considered. Please submit abstracts by e-mail, with a subject header HESG ABSTRACT and include the abstract in the BODY of the message to: hesg2010@ucc.ie

The HESG meeting will follow its standard format with papers submitted in advance, introduced and reviewed by a discussant other than the author.

Galama and Kapteyn: Grossman's Missing Threshold

Grossman’s Missing Health Threshold 

Author info | Abstract | Publisher info | Download info | Related research | Statistics

Author Info

Titus J. Galama (RAND Corporation)
Arie Kapteyn (RAND Corporation)

Abstract

We present a generalized solution to Grossman’s model of health capital (1972), relaxing the widely used assumption that individuals can adjust their health stock instantaneously to an “optimal” level without adjustment costs. The Grossman model then predicts the existence of a health threshold above which individuals do not demand medical care. Our generalized solution addresses a significant criticism: the model’s prediction that health and medical care are positively related is consistently rejected by the data. We suggest structural and reduced form equations to test our generalized solution and contrast the predictions of the model with the empirical literature.

8th European Conference on Health Economics; July 2010

The 2010 conference will be hosted by the Finnish Society for Health Economics in Helsinki.

Deadline 15 December 2009.

Main themes of ECHE 2010
01. Economics of ageing
02. Economics of information technology in health care
03. Economics of prevention and health promotion
04. Economics of social care
05. Health care financing and provision
06. Implementing health economics
07. Macro economics, health and health care
08. Migration, health and labour markets
09. New developments in the theory and methodology of health economics
10. Performance measurement in health care systems
11. Pharmaceutical markets
12. Valuing health
13. Economic evaluation

BMI and Health Status

The flaws of using body mass index as a measure for overall health status are apparent. It is a 19th century technique which ignores the distribution of both muscle mass and bone in the body. In addition, the relationship between and health status is likely to be non-monotonic, most likely quadratic.

However, the use of BMI in research does have some advantages. It is very quick and inexpensive to measure. In addition, it is plausible that BMI is a strong indicator of individual's health preferences and behaviours. Also, BMI is a continuous metric. Therefore, if we choose to use BMI as a proxy for health status we do not have to constrict ourselves to discrete choice statistics when estimating the conditional distribution for 'health'.

The way in which BMI is used in estimation strategies needs to be redefined. BMI's definition of 'overweight' is outdated, and does not recognise that the population has become bigger, stronger and healthier in the last 150 years. Bone structures with greater density and increased muscle mass are not the same as body-fat increases. They are health promoting, not health deterring. Obesity is rising, and the negative health effects are undeniable. However, the shift from 'normal' BMI to 'over-weight' BMI and the negative health outcomes are dubious. For example, Romero-Corral et al. show how coronary deaths amongst 'over-weight' BMI cases are lower those individual's defined as having 'normal' BMI.

So how should the eager researcher approach this issue? In my opinion, we should accept that the bounds defined by the BMI scale are now invalid and have no basis acting as a proxy for overall health. The mean of health and BMI has shifted in over the last century, however I would argue that the new mean indicates improvements in health - strongly supported by life-expectancy increases, height increases, etc. - and that it is the deviations away from this mean which give a more precise measure of overall health status. One estimation strategy which maintains the continuous properties of this metric would be to measure BMI in z-scores (deviations from the mean controlling for the size of the standard deviation) or the z-score squared.

Call for Papers: Health Economics Association of Ireland

Call for Papers: Health Economics Association of Ireland (HEAI)
Venue: The ESRI, Whitaker Square, Sir John Rogerson’s Quay, Dublin 2

Date: 22/10/2009
Time: 12.30 to 5.00 pm

The Health Economics Association of Ireland (HEAI) holds regular meetings where work in progress by participants is presented and discussed. The papers presented typically focus on issues of relevance to Irish health policy makers, applying health economic techniques to Irish and European data.

The next HEAI meeting will be held at the Economic and Social Research Institute (ESRI) on Thursday 22nd October 2009, 12.30 – 5pm.

We are currently seeking submissions for the next HEAI meeting. If you would like to be considered, please submit a short abstract to either Anne Nolan (anne.nolan@esri.ie) or Samantha Smith (samantha.smith@esri.ie) by Friday
4th September 2009.

Health reform can boost economy - Obama aide

Christina Romer, White House economic adviser, says overhauling health care may juice GDP and boost labor. More on this story from CNN.

How To Improve Econometric Analysis Using Data from Google Trends - They Can Predict The Flu

In the current edition of the Economist, there is an article on how data from Google Trends can help predict economic statistics before they become available. For example, using data on searches for trucks and SUVs to predict the monthly sales of motor vehicles reduces the average error by up to 18% compared with the predictions from a model that did not incorporate the search data. These findings are from a new economics paper written Hal Varian, the Chief Economist at Google, with Hyunyoung Choi, also at Google. (There is a link to the Google working paper here on the Google Research Blog).

The authors argue that fluctuations in the frequency with which people search for certain words or phrases online can improve the accuracy of the econometric models used to predict, for example, retail-sales figures or house sales. "Actual numbers for such things are usually available only with a lag. But Google’s search data are updated every day, so they can in theory capture shifts in consumer behaviour before official numbers are released."

These data are available through a site called Google Trends; this software has been discussed on the blog quite a few times: here in relation to predicting economic sentiment from search engine behaviour.

I mentioned Gord Hotchkiss from searchengineland.com, who asked in the middle of 2008 "what if our mood turns to anxiety about the future? We still search, but we search for different things. We search for information needed to help us weather the storm. Or, we search out of a desperate desire need to know just how bad things are." To illustrate, Hotchkiss presents the following Google Trend graph which shows the relative search volume and news coverage volume of "house plans" (blue line) and "foreclosures" (red line) in America over the last few years:




The Varian and Choi paper discusses how for some things, like retail sales, the categories into which Google classifies its search-trend data correspond closely to what people may want to predict, such as the sales of a particular brand of car. For others, like sales of houses, things are less clear. It appears that searches for estate agents work better than those for home financing.

Some experimentation that I have done with with the Trends software has convinced me that the selection of the keyword is a crucial consideration when trying to analyse search volume. For example, the use of "Bush", "George Bush" and "George Bush Jr" produces very different results. So how can this issue be addressed? The answer may be to find the most popular keywords related to a core question, and to aggregate these for analysis. I have yet to find an aggregation function for keywords in Google Trends, but I have discovered a website that provides information about the most popular keywords used in web searches: www.Sitepsych.com

A list of the top 200 search terms that people use, week by week or month by month, is available for free from Sitepsych. A casual inspection of the top 200 list over a 90 day period, quickly tells you that the most popular things that people are looking for on the web are sex, music, games, dogs, golf, the weather and map-directions. Sex and music dominate.

Getting back to the Google Trends software, I noted before that Google lets users get their hands dirty with the secondary data. In fact, Varian and Choi write on the Google Research Blog that they want forecasting wannabes to download some Google Trends data and try to relate it to other economic time series. If you find an interesting pattern, they invite you to post your findings on a website and send a link to econ-forecast@google.com. They will report on the most interesting results in a later blog post.

I'm thinking of putting together something on when the recession entered the public consciousness, with particular reference to Ireland. Was this a slow-burning process or where there shocks? I suspect it was largely the former but with a preliminary shock in August 2007, a subsequent shock in August 2008 and a critical threshold in November 2008. Did it come through media reference first or through search volume? Again, I suspect that it was largely the former but that there was convergence over time. If the temporal evolution is distinct, can I show that one affected the other? This seems tricky. Should I expect non-stationarity in both series? I definitely think so.

For a list of links to all the software mentioned above, and a discussion of how online search statistics may help drive Irish economic recovery, see this post from earlier on the blog: Web-based Technology and the Recovery - What Do Irish Consumers Want?

Finally, below is a video from Google.org which shows that certain search terms are good indicators of flu activity. Google Flu Trends uses aggregated Google search data to estimate flu activity up to two weeks faster than traditional flu surveillance systems. There was an article published about this in Nature during February: Detecting influenza epidemics using search engine query data.

Anchoring Vignettes and the International Comparison of Public Sector Performance

Nigel Rice, Silvana Robone, and Peter C. Smith (from the Centre for Health Economics, University of York) have written a paper on the use of anchoring vignettes to enhance the international comparability of public sector performance.

Using data on health systems responsiveness across 18 OECD countries (contained within the World Health Survey), the authors outline the issues that arise in comparative inference that relies on respondent self-reports. The problem of reporting bias is described and illustrated together with potential solutions brought about through the use of anchoring vignettes. The utility of vignettes to aid cross-country analyses and its implications for comparative inference of health system performance are discussed.

healthstat

The HSE "healthstat" system has been in the news throughout the day. I have not given this a thorough look yet but its worth thinking about whether this could be used to provide some baby-steps in measuring the effect of inputs into better healthcare in Irish hospitals. In general, the structure of Irish hospital data makes publishing in academic journals and building up a science around health policy very difficult. At first glance, this looks like a potential improvement.

I would strongly encourage the people working on it to make the data available in a standard analytical form and to get some people to start analysing it. At present, the charts are available for each hospital so its clearly not the case that there is a major issue with sensitivity of this data.

Looking at how some of these measures react to inputs into the hospitals would be good. For example, Mayo has been hauled through the press as the worst hospital in terms of scores. But is this correcting for resources? In general, it would be really interesting for someone to do some simple regressions on these output metrics on things like scale, staff-size, staff composition and so on.

http://www.hse.ie/eng/Healthstat/about/