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Quality-adjusted life-years (QALYs) and disability-adjusted life-years (DALYs) are commonly used in cost-effectiveness analysis (CEA) to measure health benefits. We sought to quantify and explain differences between QALY- and DALY-based cost-effectiveness ratios, and explore whether using one versus the other would materially affect conclusions about an intervention's cost-effectiveness.
Methods
We identified CEAs using both QALYs and DALYs from the Tufts Medical Center CEA Registry and Global Health CEA Registry, with a supplemental search to ensure comprehensive literature coverage. We calculated absolute and relative differences between the QALY- and DALY-based ratios, and compared ratios to common benchmarks (e.g., 1× gross domestic product per capita). We converted reported costs into US dollars.
Results
Among eleven published CEAs reporting both QALYs and DALYs, seven focused on pharmaceuticals and infectious disease, and five were conducted in high-income countries. Four studies concluded that the intervention was “dominant” (cost-saving). Among the QALY- and DALY-based ratios reported from the remaining seven studies, absolute differences ranged from approximately $2 to $15,000 per unit of benefit, and relative differences from 6–120 percent, but most differences were modest in comparison with the ratio value itself. The values assigned to utility and disability weights explained most observed differences. In comparison with cost-effectiveness thresholds, conclusions were consistent regardless of the ratio type in ten of eleven cases.
Conclusions
Our results suggest that although QALY- and DALY-based ratios for the same intervention can differ, differences tend to be modest and do not materially affect comparisons to common cost-effectiveness thresholds.
Host shifts of parasites are often causing devastating effects in the new hosts. The Varroa genus is known for a lineage of Varroa destructor that shifted to the Western honey bee, Apis mellifera, with disastrous effects on wild populations and the beekeeping industry. Despite this, the biology of Varroa spp. remains poorly understood in its native distribution range, where it naturally parasitizes the Eastern honey bee, Apis cerana. Here, we combined mitochondrial and nuclear DNA analyses with the assessment of mite reproduction to determine the population structure and host specificity of V. destructor and Varroa jacobsonii in Thailand, where both hosts and several Varroa species and haplotypes are sympatric. Our data confirm previously described mite haplogroups, and show three novel haplotypes. Multiple infestations of single host colonies by both mite species and introgression of alleles between V. destructor and V. jacobsonii suggest that hybridization occurs between the two species. Our results indicate that host specificity and population genetic structure in the genus Varroa is more labile than previously thought. The ability of the host shifted V. destructor haplotype to spillback to A. cerana and to hybridize with V. jacobsonii could threaten honey bee populations of Asia and beyond.
Decision-makers in low- and middle-income countries (LMICs) often must prioritize health spending without quantitative benchmarks for the value of their purchases. The Tufts Global Health Cost-Effectiveness Analysis (GH CEA) Registry (healtheconomicevaluation.org/GHCEARegistry/) is a freely-available, curated and standardized dataset designed to address this need.
Methods
All indexed English-language articles published between 1995 and 2017 are currently included in the GH CEA Registry. Studies are limited to those reporting cost-effectiveness in terms of cost per disability-adjusted life years (DALYs) averted, a commonly-employed metric in global health. Abstracted data include intervention type, comparator(s), country, funding source, study characteristics (e.g., perspective, time horizon), primary study findings, sensitivity analyses, and disaggregated data on costs and DALYs. Study quality is assessed using a numerical scoring system (from 1-7, higher scores indicating better quality) based on accuracy of findings and comprehensive reporting of methods and results.
Results
To date, 620 articles have been included in the GH CEA Registry. Among LMICs, studies have been conducted primarily in Sub-Saharan Africa (41 percent) or South Asia (34 percent), have focused on communicable diseases (67 percent), and have involved immunization, educational, or pharmaceutical interventions (67 percent). As a priority-setting example, seven percent of interventions from higher-quality studies (ratings of 5 or higher) were reported to be cost-saving (i.e., lower costs and greater DALYs than standard care), two-thirds of which involved primary disease prevention (e.g., immunization, educational or behavioral interventions).
Conclusions
The GH CEA Registry is a new tool for decision-makers in LMICs, particularly those without a formal health technology assessment infrastructure but with a remit for providing access to essential, cost-effective health interventions. New functions are under development, including league tables for priority ranking, a repository for shared models, and tools for enhancing transferability between settings.
The outermost “crust” and an underlying, compositionally distinct, and denser layer, the “mantle,” constitute the silicate portion of a terrestrial planet. The “lithosphere” is the planet’s high-strength outer shell. The crust records the history of shallow magmatism, which along with temporal changes in lithospheric thickness, provides information on a planet’s thermal evolution. We focus on the basic structure and mechanics of Mercury’s crust and lithosphere as determined primarily from gravity and topography data acquired by the MESSENGER mission. We first describe these datasets: how they were acquired, how the data are represented on a sphere, and the limitations of the data imparted by MESSENGER’s highly eccentric orbit. We review different crustal thickness models obtained by parsing the observed gravity signal into contributions from topography, relief on the crust–mantle boundary, and density anomalies that drive viscous flow in the mantle. Estimates of lithospheric thickness from gravity–topography analyses are at odds with predictions from thermal models, thus challenging our understanding of Mercury’s geodynamics. We show that, like those of the Moon, Mercury's ellipsoidal shape and geoid are far from hydrostatic equilibrium, possibly the result of Mercury's peculiar surface temperature distribution and associated buoyancy anomalies and thermoelastic stresses in the interior.
OBJECTIVES/SPECIFIC AIMS: Costs associated with the treatment of skin diseases accounted for greater than 4% of total US healthcare spending in 2013, an increase of $46 billion (170%) since 2004. Considering the increase in novel treatments and spending, cost-utility analyses (CUAs) may provide a better understanding of costs in dermatology. In this study, we conduct a systematic overview of study quality among CUAs related to dermatology. METHODS/STUDY POPULATION: We queried studies from the Tufts Medical Center Cost-Effectiveness Analysis Registry (www.cearegistry.org), a database supplying information on all peer-reviewed cost-effectiveness analysis through 2014. Database methodology was previously discussed here. We queried studies using keywords from the 24 major skin disease categories (e.g., diseases relating to actinic damage were searched by using “actinic,” “actinic keratosis”). We collected data on study design, reporting methods, and analyzed relevant data stratified by 2 time-periods (1976–2008 and 2009–2014) chosen to encompass a comparable number of studies. RESULTS/ANTICIPATED RESULTS: In total, 42 and 50 studies corresponding to the 2 time-periods were retrieved (representing 14/24 disease categories). Based on the recommended data reporting guidelines for CUAs, study quality remained largely unchanged across the 2 phases. Across the 2 time-periods, a societal perspective was used in 19% and 12% of studies, costs and (quality adjusted life-years) QALYs were discounted in 67% and 72% of studies, a correct (incremental cost-effectiveness ratio) ICER was reported in 67% and 72% of studies, and a sensitivity analysis was included in 88% and 84% of studies, respectively. DISCUSSION/SIGNIFICANCE OF IMPACT: Our findings suggest the quality of dermatology-related CUAs, as evaluated by recommended data reporting guidelines, to be generally stable during the analyzed time-periods. However, the quality of our results may be limited by the small number of CUAs within dermatology (10/24 disease categories did not have CUAs across any time-period). Moving forward, we encourage researchers within dermatology to pursue additional investigation towards cost-effective practices while adhering closely to recommended quality reporting guidelines for CUAs.
This article began as a study of the structure of infinite permutation groups $G$ in which point stabilisers are finite and all infinite normal subgroups are transitive. That led to two variations. One is the generalisation in which point stabilisers are merely assumed to satisfy min-n, the minimal condition on normal subgroups. The groups $G$ are then of two kinds. Either they have a maximal finite normal subgroup, modulo which they have either one or two minimal nontrivial normal subgroups, or they have a regular normal subgroup $M$ which is a divisible abelian $p$-group of finite rank. In the latter case the point stabilisers are finite and act irreducibly on a $p$-adic vector space associated with $M$. This leads to our second variation, which is a study of the finite linear groups that can arise.
In May 2014, soon after the MA Conference in Nottingham, and soon after the passing of Roger Wheeler, a staunch member of the MA, who had been my teacher at school, I had the idea that my presidential address in April 2016 might be entitled ‘Inspiring Teachers’. The concept was a talk that might trace my mathematical experiences from grammar school sixth form, through my development in retirement as a contributor to masterclasses for the UK Mathematics Trust and the Royal Institution, learning from the students and from the inspiring teachers at whose masterclasses I assist, to the small understanding of Key Stage 2 Mathematics that I am gradually acquiring through an hour a week with some Year 6 students and their remarkable teachers in a local primary school.
A month or so later, when the organising committee was giving shape to Conference 2016, my words were taken as the title of the conference itself. It is deliberately ambiguous and it was gratifying to me to find this last April that its ambiguity had struck melodious chords with other speakers. My presidential address, however, was conceived as a lecture. Like all my lectures it was designed to be an oral presentation. It was not designed to be written down and published as an article. Please bear that in mind gentle reader, and judge accordingly. If you find something of value here I shall be delighted; if not, I shall not be surprised.
Objectives: The Centers for Medicare and Medicaid Services (CMS) issues National Coverage Determinations (NCDs) for medical interventions expected to have a significant impact on Medicare, the health insurance program for US citizens aged 65 years and older and certain people with disabilities under the age of 65 years. The objective of this study was to evaluate NCDs issued from 1999 to 2013 to identify key trends, and to discuss implications for future CMS policy.
Methods: We used the Tufts Medical Center Medicare National Coverage Determination Database to examine characteristics of NCDs from 1999 through 2013. We examined various characteristics of NCDs, including: whether the intervention under review is used for prevention or treatment of disease, the type of intervention considered, evidence limitations cited by CMS, and coverage determination outcome. We evaluated longitudinal trends in categorical and continuous variables in the database, using Cochran-Armitage trend tests and linear regression, respectively.
Results: We found that NCDs increasingly focus on preventive care (p = 0.072), pertain to diagnostic imaging (p = 0.033), and evaluate health education/behavioral therapy interventions (p = 0.051). CMS increasingly cites the lack of relevant outcomes (p = 0.019) and the lack of applicability of study results to the Medicare population (p < 0.001) as evidence limitations. CMS less often restricts coverage to certain population subgroups in NCDs (p < 0.001), but increasingly applies coverage with evidence development policies (p < 0.001).
Conclusions: Identified trends reflect broader changes in Medicare as CMS shifts its focus from treatment to prevention of disease, addresses potentially overutilized technologies, and attempts to issue flexible coverage policies.
Objectives: In recent years, there has been growth in the use of health technology assessment (HTA) for making decisions about the reimbursement, coverage, or guidance on the use of health technologies. Given this greater emphasis on the use of HTA, it is important to develop standards of good practice and to benchmark the various HTA organizations against these standards.
Methods: This study discusses the conceptual and methodological challenges associated with benchmarking HTA organizations and proposes a series of audit questions based on a previously published set of principles of good practice.
Results and Conclusions: It is concluded that a benchmarking exercise would be feasible and useful, although the question of who should do the benchmarking requires further discussion. Key issues for further research are the alternative methods for weighting the various principles and for generating an overall score, or summary statement of adherence to the principles. Any weighting system, if developed, would need to be explored in different jurisdictions to assess the extent to which the relative importance of the principles is perceived to vary. Finally, the development and precise wording of the audit questions requires further study, with a view to making the questions as unambiguous as possible, and the reproducibility of the assessments as high as possible.
The Tufts Cost-Effectiveness Analysis (CEA) Registry (www.cearegistry.org) is a publicly available comprehensive database of cost-utility analyses of health interventions published in the peer-reviewed medical and public health literature. This article discusses the database structure, methodology of data extraction, current trends in cost-utility analyses and impact of the Registry.
As in the past, the primary activity of the IAU Working Group on Cartographic Coordinates and Rotational Elements has been to prepare and publish a triennial (“2009”) report containing current recommendations for models for Solar System bodies (Archinal et al. (2011a)). The authors are B. A. Archinal, M. F. A'Hearn, E. Bowell, A. Conrad, G. J. Consolmagno, R. Courtin, T. Fukushima, D. Hestroffer, J. L. Hilton, G. A. Krasinsky, G. Neumann, J. Oberst, P. K. Seidelmann, P. Stooke, D. J. Tholen, P. C. Thomas, and I. P. Williams. An erratum to the “2006” and “2009” reports has also been published (Archinal et al. (2011b)). Below we briefly summarize the contents of the 2009 report, a plan to consider requests for new recommendations more often than every three years, three general recommendations by the WG to the planetary community, other WG activities, and plans for our next report.
To understand the interactions between production patterns common to children regardless of language environment and the early appearance of production effects based on perceptual learning from the ambient language requires the study of languages with diverse phonological properties. Few studies have evaluated early phonological acquisition patterns of children in non-Indo-European language environments. In the current study, across- and within-syllable consonant–vowel co-occurrence patterns in babbling were analyzed for a 6-month period for seven Ecuadorean Quichua learning children who were between 9 and 17 months of age at study onset. Their babbling utterances were compared to the babbling of six English-learning children between 9 and 22 months of age. Child patterns for both languages were compared with Quichua and English ambient language patterns. Babbling output was highly similar for the child groups: Quichua and English children's babbling demonstrated similar predicted within-syllable (coronal-front vowel, labial-central vowel, dorsal-back vowel) patterns, and across-syllable manner variegation patterns for consonants. These patterns were observed at significantly greater rates in the child groups than in the respective adult language input patterns, suggesting production system influences common to children across languages rather than ambient language perceptual learning effects during these children's babbling period.
The triple product property (TPP) for subsets of a finite group was introduced by Henry Cohn and Christopher Umans in 2003 as a tool for the study of the complexity of matrix multiplication. This note records some consequences of the simple observation that if (S1,S2,S3) is a TPP triple in a finite group G, then so is (dS1a,dS2b,dS3c) for any a,b,c,d∈G.
Let si:=∣Si∣ for 1≤i≤3. First we prove the inequality s1(s2+s3−1)≤∣G∣ and show some of its uses. Then we show (something a little more general than) that if G has an abelian subgroup of index v, then s1s2s3 ≤v2 ∣G∣.
An automated technique for the mapping of nanocrystal phases and orientations in a transmission electron microscope (TEM) is briefly described. It is primarily based on the projected reciprocal lattice geometry that is extracted automatically from precession electron diffraction (PED) enhanced spot patterns. The required hardware allows for a scanning-precession movement of the primary electron beam on the crystalline sample and can be interfaced to any newer or older mid-voltage TEM. Comprehensive open-access crystallographic databases that may be used in support of this technique are mentioned.
Thank you for the opportunity to respond to the letter by Gibson and Little. The authors raise several points that require a response. First, they claim that we inaccurately characterized the DERP/Washington State Medicaid agency, and did not appreciate that the DERP and the Washington State Medicaid agency have different missions. On the contrary, however, we fully recognized that DERP's mission is to conduct systematic reviews and not to make recommendations, whereas Washington State uses the reviews in making recommendations for their Medicaid enrollees. We specifically noted in the study that “Washington Medicaid is one of fourteen participants in the DERP. DERP researchers conduct health technology assessments for drug classes. Participants in the DERP, such as the Washington Medicaid program, retain local authority for interpreting DERP reports and for decision making regarding which drugs to pay for.” We chose to analyze DERP/Washington State as a single entity for our exercise because we were interested in analyzing the link between the HTA conducted and the decisions that follow them.
A k-multiset is an unordered k-tuple, perhaps with repetitions. If x is an r-multiset {x1, …, xr} and y is an s-multiset {y1, …, ys} with elements from an abelian group A the tensor product x ⊗ y is defined as the rs-multiset {xi yj | 1 ≤ i ≤ r, 1 ≤ j ≤ s}. The main focus of this paper is a polynomial-time algorithm to discover whether a given rs-multiset from A can be factorised. The algorithm is not guaranteed to succeed, but there is an acceptably small upper bound for the probability of failure. The paper also contains a description of the context of this factorisation problem, and the beginnings of an attack on the following division-problem: is a given rs-multiset divisible by a given r-multiset, and if so, how can division be achieved in polynomially bounded time?
Previously, our group—the International Working Group for HTA Advancement—proposed a set of fifteen Key Principles that could be applied to health technology assessment (HTA) programs in different jurisdictions and across a range of organizations and perspectives. In this commentary, we investigate the extent to which these principles are supported and used by fourteen selected HTA organizations worldwide. We find that some principles are broadly supported: examples include being explicit about HTA goals and scope; considering a wide range of evidence and outcomes; and being unbiased and transparent. Other principles receive less widespread support: examples are addressing issues of generalizability and transferability; being transparent on the link between HTA findings and decision-making processes; considering a full societal perspective; and monitoring the implementation of HTA findings. The analysis also suggests a lack of consensus in the field about some principles—for example, considering a societal perspective. Our study highlights differences in the uptake of key principles for HTA and indicates considerable room for improvement for HTA organizations to adopt principles identified to reflect good HTA practices. Most HTA organizations espouse certain general concepts of good practice—for example, assessments should be unbiased and transparent. However, principles that require more intensive follow-up—for example, monitoring the implementation of HTA findings—have received little support and execution.