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Overview of attention for article published in Health and Quality of Life Outcomes, January 2003
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About this Attention Score

  • In the top 5% of all research outputs scored by Altmetric
  • Among the highest-scoring outputs from this source (#12 of 2,039)
  • High Attention Score compared to outputs of the same age (98th percentile)

Mentioned by

3 news outlets
2 blogs
17 tweeters
3 Wikipedia pages
1 Google+ user


156 Dimensions

Readers on

463 Mendeley
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Published in
Health and Quality of Life Outcomes, January 2003
DOI 10.1186/1477-7525-1-80
Pubmed ID

Luis Prieto, José A Sacristán


The quality-adjusted life-year (QALY) is a measure of the value of health outcomes. Since health is a function of length of life and quality of life, the QALY was developed as an attempt to combine the value of these attributes into a single index number. The QALY calculation is simple: the change in utility value induced by the treatment is multiplied by the duration of the treatment effect to provide the number of QALYs gained. QALYs can then be incorporated with medical costs to arrive at a final common denominator of cost/QALY. This parameter can be used to compare the cost-effectiveness of any treatment. Nevertheless, QALYs have been criticised on technical and ethical grounds. A salient problem relies on the numerical nature of its constituent parts. The appropriateness of the QALY arithmetical operation is compromised by the essence of the utility scale: while life-years are expressed in a ratio scale with a true zero, the utility is an interval scale where 0 is an arbitrary value for death. In order to be able to obtain coherent results, both scales would have to be expressed in the same units of measurement. The different nature of these two factors jeopardises the meaning and interpretation of QALYs. A simple general linear transformation of the utility scale suffices to demonstrate that the results of the multiplication are not invariant. Mathematically, the solution to these limitations happens through an alternative calculation of QALYs by means of operations with complex numbers rooted in the well known Pythagorean theorem. Through a series of examples, the new calculation arithmetic is introduced and discussed.

Twitter Demographics

The data shown below were collected from the profiles of 17 tweeters who shared this research output. Click here to find out more about how the information was compiled.

Mendeley readers

The data shown below were compiled from readership statistics for 463 Mendeley readers of this research output. Click here to see the associated Mendeley record.

Geographical breakdown

Country Count As %
United Kingdom 5 1%
Spain 3 <1%
United States 2 <1%
Brazil 2 <1%
South Africa 1 <1%
Italy 1 <1%
Bulgaria 1 <1%
Portugal 1 <1%
Unknown 447 97%

Demographic breakdown

Readers by professional status Count As %
Student > Master 93 20%
Researcher 62 13%
Student > Bachelor 55 12%
Student > Ph. D. Student 49 11%
Student > Postgraduate 38 8%
Other 95 21%
Unknown 71 15%
Readers by discipline Count As %
Medicine and Dentistry 132 29%
Nursing and Health Professions 31 7%
Economics, Econometrics and Finance 29 6%
Agricultural and Biological Sciences 26 6%
Psychology 26 6%
Other 128 28%
Unknown 91 20%

Attention Score in Context

This research output has an Altmetric Attention Score of 58. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 30 November 2021.
All research outputs
of 19,541,023 outputs
Outputs from Health and Quality of Life Outcomes
of 2,039 outputs
Outputs of similar age
of 139,604 outputs
Outputs of similar age from Health and Quality of Life Outcomes
of 1 outputs
Altmetric has tracked 19,541,023 research outputs across all sources so far. Compared to these this one has done particularly well and is in the 97th percentile: it's in the top 5% of all research outputs ever tracked by Altmetric.
So far Altmetric has tracked 2,039 research outputs from this source. They receive a mean Attention Score of 4.4. This one has done particularly well, scoring higher than 99% of its peers.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 139,604 tracked outputs that were published within six weeks on either side of this one in any source. This one has done particularly well, scoring higher than 98% of its contemporaries.
We're also able to compare this research output to 1 others from the same source and published within six weeks on either side of this one. This one has scored higher than all of them