General Quality Criteria Research Articles

Taking the natural geography book of the eleventh grade of high school under the light of the general quality measurements in the view of teachers and expert supervisors.

This research is to build a scale for evaluating the natural geography book of high school under the light of general quality criteria. Knowing theextentof having a general quality measure in the geography book of the11th grade of literary readings in the eyes of teachers and expert supervisors, according to the gender change (male and female) General quality in the booklet to achieve these goals, the researcher used the method of description and analysis as an example of the research which was made in (70) teachers and supervisors of geography in male and female gender All three educations in the east and west of Sulaimaniyah and Chamchamal education for the school year (2021-2022), which were selected in a symbolic way, research tools Which consisted of a survey form consisting of 86 sections, which was divided into (7) items, and this was the benefit of the previous research. The researcher after preparing the tool and directing it The truth and stability of using Person's partner in the rate of (0.815) then the researcher also performed it on the example of the research, after analyzing and presenting the survey to Using Person's co-ordination, appropriate center, Test (T.test) after being certain of the truth, the researcher used the(spss) statistical program. Finally, the researcher reached the goals that each (7) sections of the 11th grade natural geography book which are (objective, they were (aim, art, activity, motivation, teaching, language, subject, content) and they were not accepted.

МЕХАНИЧЕСКИЕ СВОЙСТВА СВЕРХВЫСОКОПРОЧНОГО ФИБРОБЕТОНА С РАЗЛИЧНЫМ ВИДОМ СТАЛЬНОЙ ФИБРЫ

The article examines the influence of steel fiber type and volumetric content on the mechanical properties of UHPFRC. Five fiber types were used: corrugated 15/0.3 and 22/0.3 mm, straight 13/0.3 and 13/0.2 mm, and hooked-end 30/0.5 mm. The fiber volume content ranged from 0 to 3%. During the experimental studies, compressive strength, flexural strength, as well as the flexural fracture energy were determined. It has been discovered that an increase in the volumetric content of steel fiber results in an enhancement of all the properties under consideration, irrespective of the type of fiber. The fiber has the biggest effect on the bending fracture energy and the least on the compressive strength. Linear relationships between the mechanical characteristics of UHPFRC and the fiber factor were established, which reflects the volumetric content, length, and diameter of an individual fiber. The slope angle of the approximating lines of the “compressive strength-fiber factor” and “flexural strength-fiber factor” relationships takes on different values depending on the type of fiber used. The highest slope angle is found for corrugated fiber. It was discovered that there is a threshold value of the fiber factor, upon reaching which the steel fiber leads to an increase in the flexural strength of the UHPFRC. According to a generalized quality criterion it has been determined that corrugated fiber with dimensions of 22/0.3 mm is the optimal substitute for straight fiber 13/0.2 mm, which is widely utilized for the production of Ultra-High Performance Fiber-Reinforced Concrete

Simulation of the engineering network in the area of one regulator

Theproposed article present problems that update the issue of mathematical modeling of the system process of designing of new and reconstruction of old engineering networks in the conditions of their perspective development. The analysis of researches in the field of designing of engineering networks taking into account uncertainty of the information is given. The main material of the article is devoted to the construction of a mathematical model of the problem of the network synthesis in the area of action of one regulator of the supply of the target product as component of the developing engineering network design process. The list of questions to be answered when designing a network is given. The problem is solved on a subgraph of the redundant graph of the general design process. It distinguishes the vertex of the regulatorof the supply of the target product, the vertices of the consumers of the target product fed by the regulator, and the permissible communications (arcs) between the consumers. Each communication is matched with its length, indicatorof reliability of functioning, characteristics of quality criteria per unit of communicationlength. Each vertex is matched with an indicatorof reliability of providing the target product. Since thequality criteria are fuzzy numbers with their membership functions, the criteria are normalized forcomparison.Corresponding indicatorfor them, together with the weighting factors, form a generalized quality criterion per unit of communicationlength. The structure of the network has a ring character, for construction of which the vertices of thegraph are divided into subset taking into account the radius of the ring. On the basis of such a graph, a basic mathematical modeling of the Boolean programming problem was built, in which generalized quality criterion are optimized taking into account the restrictions on ensuring supply reliability indicators for consumers. The decomposition process was applied to the constructed model. It allows the solution of the general problem to be reduced to the solution of theBoolean programming problem separately for each vertex in the framework of the search for optimal routes according to the constructed criterion between the previous set of vertices and the set of vertices to which the selected vertex belongs. The work proves the possibilities of such an approach. Based on the developed decomposition, an algorithm for solving the problem of the network synthesis in the area of action of one regulator of the supply of the target productis proposed.

ANALYTICAL DESIGN OF COMPOSITES IN TERMS OF SYSTEMS ANALYSIS

Introduction. The development of composite materials is considered with account for the shifts of paradigms based on the basic models of the continuous self-developing environment towards paradigms based on the models of the structured self-developing environment using the ideas and methods of the system approach and synergetics. The system approach can: reduce or even eliminate the uncertainty inherent to the problem to be solved; reconstruct it in models meeting the objectives of the study; identify objects, properties, and relationships in the system under consideration, taking into account the mutual influence of the external environment. Methods. It is shown that the structural organization of the material determines the design of the product or structure and largely determines the functional properties of the entire system. Composite materials are considered as large, complex systems formed based on a modular principle; material properties are determined on the basis of autonomous studies of individual subsystems. Results. It is assumed that individual subsystems have a certain degree of autonomy; it is possible to introduce customizable reference models with the simultaneous decentralization of modules by inputs; the conditions for transferring the results of autonomous studies to the system as a whole are determined by the completeness of understanding the processes of the formation of the structure and properties of the system. In the development of composites, the relative importance, the mutual utility of the quality criteria, a reasonable balance between the internal logic of science and its practical significance are taken into account. Partial criteria are analyzed, and a generalized quality criterion for the building material is formalized. The following is considered: the complexity of the object of study (multi-dimensionality, multi-connectedness, incompleteness of diagnostic information), diagnostic interpretation of the analyzed factors, the probabilistic nature of diagnostic information (using methods of both concrete and abstract-logical cognition; each new logical stage continues the previous one and serves as a prerequisite for the previous one).

The effect of carob, orange and carrot pulps on physical, chemical and microbiological properties of Turkish delight

In this study the possibility of using carob, orange and carrot pulps, food industry wastes rich in dietary fiber and healthy components which have superior advantages on human health, was investigated in Turkish delight production. For this purpose, Turkish delight was produced by replacing Turkish delight dough with dried and ground carob, orange and carrot pulps at 3%, 6% and 9% levels. The produced Turkish delight samples were examined in terms of physical, chemical and microbial properties at different storage periods (0, 15th and 30th days). Pulp type, addition level and storage time had a statistically significant (p˂0.01) effect on dry matter, water soluble dry matter, ash, pH, total acidity, total phenolic substance, antioxidant activity, L*, a*,b* color values and total color change (ΔE) of the Turkish delight samples. The increase in the pulp addition level was generally effective in decreasing the dry matter and water soluble dry matter values of the Turkish delight samples while it was effective in increasing the ash content, total phenolic substance and antioxidant activity values. It was determined that Turkish delight samples containing 9% carob pulp on day 0 exhibited higher values in terms of total phenolic substance (193.77mgGAE/100g) and antioxidant activity (77.88%). It has also been determined that all three pulp types can be used up to 9% in the Turkish delight production in terms of general quality criteria and sugar content of the Turkish delight can be reduced at the rate of 7.8%, 8.1% and 8.2% by using the orange, carob and carrot pulp at this level, respectively. In addition it was determined that the produced Turkish delight samples were generally within acceptable limits in terms of yeast and mold counts.

The road to commercialisation of an unutilised Cyclopia species for herbal tea production – the case of Cyclopia pubescens

• C. pubescens was shown to be suitable for production of honeybush herbal tea. • Its sensory profile is similar to that of commercially-cultivated C. subternata . • Other quality parameters were similar to that of C. subternata and C. genistoides . • High-temperature oxidation reduces the xanthone content more than 70%. Cyclopia pubescens is an unutilised species that could potentially be used for production of honeybush tea, if general quality criteria for the herbal tea product could be met. This species is at risk of extinction in the wild, but if suitable for production of honeybush herbal tea, its cultivation could be stimulated. Cyclopia pubescens shoots were used to produce conventional (oxidised) honeybush tea and its quality parameters for the infusion were compared with those of the commercially-cultivated Cyclopia species, C. subternata and C. genistoides . Oxidised C. pubescens had a similar sensory profile to that of C. subternata, displaying ‘woody’, ‘fynbos-floral’ ‘fynbos-sweet’ and ‘sweet spice’ aromas and a slightly sweet taste. The soluble solids concentration, colour and turbidity of the infusions, prepared from the herbal teas of the three species, were similar. The high-temperature oxidation process, essential for the development of the sought-after sensory profile of honeybush tea, reduced the phenolic concentration of the C. pubescens infusions, in particular, the concentration of mangiferin and isomangiferin decreased > 70%. Despite this reduction, C. pubescens infusions would contribute ≥ 8 mg/L to the dietary intake of each of these xanthones. Cyclopia pubescens , thus, passed the first hurdle for commercial herbal tea production, but cultivation would be required as wild-harvesting of this species is not an option.

AN APPROACH WEB SERVICE SELECTION BY QUALITY CRITERIA BASED ON SENSITIVITY ANALYSIS OF MCDM METHODS

Context. The problem of QoS based Web service from the list of Web services with equal or similar functionality was considered. This task is an essential part of the processes of finding, discover, matching and using Web services on the Internet due to the numerous offerings of Web services with equal or similar functionality. The reasonable selection of a suitable Web service takes into account a lot of user’s quality requirements, such as response time, throughput, reliability, cost, etc. Such a task is usually formulated as an MCDM problem, in which the parameters are the Web service quality factors and the importance degree of these factors. The object of this research is a process of selection Web services using MCDM methods, taking into accounts the user’s preferences and requirements to the Web service quality characteristics. The subject of the research is the LSP method, which, in addition to the degree of importance of the criteria used in all MCDM methods, simulates the user’s reasoning about quality, taking into account, in particular, such characteristics of the criteria as mandatory, sufficiency, desirability, simultaneity and substitutability. Objective. The objective of the work is to develop an approach for comparing the result of using the LSP method with the results of using other MCDM methods. Method. A method for calculating the weights of input criteria that are not always explicitly specified in the LSP method was proposed. For this, the conjunctive coefficients of impact are used, which are calculated as a result of the sensitivity analysis of the Web service generalized quality criterion to changes the partial quality criteria. This method underlies the proposed approach to comparing the efficiency of the LSP method with other MCDM methods, which consists of using the obtained weights as the weights of the input criteria for the MCDM methods. Results. The developed method and approach was verified experimentally. The Web service ranking produced by the LSP method was compared with the ones produced by SAW, AHP, TOPSIS and VIKOR methods. This comparison confirmed the efficiency of the proposed method and approach. Conclusions. From the obtained results of comparing the LSP method and the MCDM methods considered in this study, it follows that the proposed method and approach provide the equivalent input conditions for these methods as for the LSP method, which is a necessary condition for the correct comparison of MCDM methods. The use of the proposed approach made it possible to study the sensitivities of the considered MCDM methods. In practical applications, this approach can be used to select a suitable MCDM method. The proposed method can be useful for creating professional evaluation systems in which it is necessary to assess the importance (weights) of tens and hundreds of quality criteria.

Chemical evaluation of the quality of nanostructures synthesized on the surface of indium phosphide

Purpose: The article proposes a methodology for determining the chemical quality criterion of porous layers synthesized on the surface of semiconductors, based on taking into account the chemical parameters of the surface that can affect the properties of nanostructures. Design/methodology/approach: The chemical quality criterion was evaluated in terms of stoichiometry, stability of structures over time, uniformity of distribution over the surface, and the presence of an oxide phase. As an example, a calculation is demonstrated for the por-InP/InP structure synthesized on a mono-InP surface. The results of calculating the chemical quality criterion were evaluated using the Harrington scale to rank samples by quality level. Findings: A chemical criterion for the quality of porous layers synthesized on the surface of semiconductors has been developed. This criterion contains a set of indicators sufficient for a comprehensive assessment of the surface condition and is universal in nature. The studies carried out make it possible to reasonably approach the determination of the modes of electrochemical processing of semiconductors and open up new perspectives in the construction of a model of self-organization of a porous structure. Research limitations/implications: The chemical quality criterion does not allow evaluating the obtained nanostructures in terms of geometric parameters. Therefore, in the future, there is a need to develop a morphological quality criterion and determine a methodology for assessing a generalized quality criterion for nanostructures synthesized on the surface of semiconductors, which may include economic, environmental, technological indicators, and the like. Practical implications: Study results are expedient from a practical point of view, since they make it possible to reasonably approach the determination of the modes of electrochemical processing of semiconductors, synthesize nanostructures with predetermined properties, and create standard samples of nanomaterial composition.Originality/value: Methodology for assessing the quality of porous semiconductors by a chemical criterion has been applied for the first time in engineering science. The article will be useful to engineers, who are engaged in the synthesis of nanostructures, researchers and scientists, as well as specialists in nanometrology.

The Experience of Designing Building Materials

The evolution of views on the development of composite materials is analyzed from the point of view of paradigm shift based on basic models of a continuous self-developing environment towards paradigms based on models of a structured self-developing environment based on ideas and methods of a systematic approach and synergetics. A system approach can reduce or even eliminate the uncertainty inherent in the problem being solved; to reconstruct it in models that meet the objectives of the study; identify objects, properties and relationships of the investigated system, taking into account the mutual influence of the external environment. It is shown that the structural organization of the material determines the structural design of the product or structure and largely determines the functional properties of the entire system. Composite materials are considered as large complex systems formed on a modular principle: integrative properties are approximately determined on the basis of autonomous studies of separate subsystems. Separate subsystems are supposed to have a certain degree of autonomy; the introduction of custom reference models with the simultaneous decentralization of modules by inputs is possible. It is shown that the conditions for transferring the results of autonomous studies to the system as a whole are determined by the completeness of understanding the processes of formation of the structure and properties of the system. When developing composites, the PATTERN method and the SATURN technology are used to determine the criteria for assessing the relative importance, mutual utility, state and timing of research and development, maintaining a reasonable balance between the internal logic of science and its practical significance. Partial criteria and formalization of the generalized quality criterion of building material are analyzed. As an illustration, the definition of flocculation conditions in a disperse system is given on the basis of its representation as a system of particles moving under the action of gravitational and pair interaction forces, interaction with boundaries and a dispersion medium. It is shown that the uniformity of the steady-state configuration and the sedimentation stability of the polydisperse system are mainly determined by the volumetric degree of filling. Given the complexity of the composite as an object of study (multidimensionality, multiconnectedness, incompleteness of diagnostic information), diagnostic interpretation of the analyzed factors, the probabilistic nature of diagnostic information the necessity of using methods of both specific and abstract logical cognition is shown (each new logical stage continues the previous one and serves as the initial prerequisite for the previous one).

Introducing the integrated, cross-sectional psycho-oncology intervention programme and PIM

Abstract From the literature and experience, we know that the quality of patient information material (PIM) has a direct impact on its utilization and therefore also on the acceptance and success of an intervention. In this brief introduction session (10 minutes), the innovative “integrated, cross-sectional psycho-oncology” (isPO) programme and the context of its implementation will be sketched. In the programmés development phase, isPO specific-PIM was developed and utilized in its early implementation phase. This will be presented to the audience. Next, an overview regarding the general PIM quality criteria: correctness of content, legibility, comprehensibility and usability in detail will be given. Finally, common guidelines, checklists and quality assessment instruments will be presented, and the role of the target group (participation degree) in the development or examination process will be critically worked out.

Combined methods for determining weight coefficients in the problems of assessing the quality of power objects

When designing power facilities, the problem usually arises of comparing their possible options for performance, taking into account consumer quality. A common and easy-to-implement method is the formation of a generalized indicator, however, subjectivity is inherent in it, given this, the task of developing algorithms and methods that objectively consider the quality indicators of an energy object becomes especially urgent. It is argued that, in accordance with the condition for making a decision on the type of the synthesizing function, the main object of uncertainty, respectively, of the quality indicator, which is inherently subjective, is the vector of the significance coefficients of the weight coefficients. The presented algorithms in conditions of uncertainty that allow you to build a generalized quality criterion for energy facilities. For a comprehensive assessment of the quality of energy facilities, it is proposed to use the methods of arbitrary summary indicators, namely: the method of arbitrary summary indicators, the method of priority of private quality indicators and the method of minimizing the deviation of the summary quality indicator. It is proposed to reduce the influence of subjective factors in determining the weight coefficients, it is advisable to use a combination of these methods. For the method of minimizing the deviation of the aggregate indicator, using the principle of objectivity, an algorithm for determining the weight coefficients has been developed, taking into account that in the area of permissible changes in parameters, the value of the criterion will be minimal. Accordingly, to solve the problem of comparing the options for constructing energy facilities, which includes the determination of weight coefficients for the formation of a composite indicator, it is necessary to use the results of expert assessment that are supplemented by calculation methods that will reduce the subjective factor that is inherent in the method of expert assessment.

Quality assessment of the fuel preparation production process at thermal power plants

The production of electrical energy from most of the thermal power plants currently in operation is achieved by converting the thermal energy generated by the combustion of hydrocarbons. At the same time, one of the central technological processes is the fuel preparation. The article considers the task of measuring the parameters of a drying unit used in dust preparation systems. A block diagram of a monitoring system with a multi-point principle for measuring process parameters is proposed. Such a plan for the placement of sensors makes it possible to implement a multi-version approach to the formation of measured parameters of the technological process, for which a generalized quality criterion is proposed.

ЩЕБЕНОЧНО-МАСТИЧНЫЙ АСФАЛЬТОБЕТОН С ИСПОЛЬЗОВАНИЕМ СЕРОВОВЛЕКАЮЩИХ ТЕХНОЛОГИЙ

One of the main reasons for reducing the service life of road asphalt pavements (the appearance and development of damage in the form of ruts, various kinds of plastic deformations, potholes, cracks, etc.) is the low quality of the used oil bitumen. The physicomechanical properties of road bitumen are subject to stricter requirements, especially for organic binders used for the production of crushed stone mastic asphalt (SMA), therefore, in authors’ view, the development of bitumen binders with enhanced physicomechanical properties is one of the key and most urgent tasks in road construction. This problem is solved by introducing various modifiers into the binder. This article presents the results of a study of bitumen modified by introducing technical sulfur into the composition. The effect of binder modification on the physicomechanical properties of road asphalt concrete is shown on the example of crushed stone mastic asphalt (SMA-20) relative to base samples made to control the dynamics of changes in the properties of composites made using sulfur-raising technologies. For a comprehensive assessment of the effectiveness of modifying crushed stone mastic asphalt concrete based on various binders, a generalized quality criterion is calculated, taking into account the calculated particular quality criteria and various values of the weight coefficients. The comparison and analysis of the obtained efficiency criteria is made.

COMPREHENSIVE APPROACH TO FEASIBILITY ANALYSIS OF NEW CONSTRUCTION MATERIALS

Science and technology, new technical and technological solutions are rapidly developing. However, the rationale for the effectiveness is still based only on economic criteria. Therefore, it is necessary to develop the universal approaches to the assessment of economic efficiency of technological solutions. A rational approach to the complex assessment of the effectiveness of the use of composite materials is the use of system analysis methods – the method of complex technical and economic indicators. The authors propose a feasibility approach in order to justify the effectiveness of technology, which assesses the cost of a new technological solution aimed at improving the quality of the material. The technological solution according to this approach is recognized as effective according to the established quality criterion (generalized quality criterion) if the maximum value of the efficiency coefficient is achieved. The presented approach, tested on high-strength lightweight fiber-reinforced concrete, shows the possibility of a comprehensive assessment of the feasibility of using new technological solutions. Using the criteria method, it has been shown that the technology of high-strength lightweight concrete with a unique set of properties has the best technical and economic efficiency of 24...39 % as compared with the conventional technology of heavy high-strength concrete.

Assessment models for the generalized quality criterion for the production processes of thermal power plants

In order to increase the information reliability of the hardware and software technology for industrial and environmental monitoring, we obtained models of the thermal power plants production processes that can give an assessment of a generalized quality criterion for the occurrence of such technological processes as the preparation of fuel, fuel combustion, removal of flue gases and suspended particles. To form the measured values of the parameters of each technological process, a multiversion approach is used, which is based on obtaining the n-th amount of measured data.

Improving separation optimization in capillary electrophoresis by using a general quality criterion

In this paper we extend the use of the quality criterion t’ to optimize separations in capillary electrophoresis (CE). The theoretical parameter t’ takes into account not only the relative separation between a given pair of compounds but also their separation from the neutral species migrating with the electroosmotic flow (EOF). Furthermore, it can be composed for complex mixtures as a global multicriterium optimization function T′, for a rapid, simple and reliable selection of optimized separation conditions by mathematical maximization. Here, we demonstrate the applicability of T′ using as a variable the electrophoretic mobility (me) for the optimization of pH in the separation of a mixture of amyloid beta (Aβ) peptide fragments. In addition, it is shown the versatility of T′ using other variables related to me, which do not require experimental measurements. This is the case with ionizable compounds as the Aβ peptide fragments, whose charge-to-mass ratios can be calculated if accurate pKa values are available in the literature. The excellent performance of T’ for Aβ peptide fragments is further validated optimizing the pH for the separation of mixtures of harmala alkaloids (HAlks) and quinolone antibiotics.

Nutritional composition of pot-pollen produced by stingless bees (Tetragonula biroi Friese) from the Philippines

ABSTRACT The commercial use of Tetragonula biroi Friese pot-pollens is strongly limited due to scarce data about its properties and composition. Eight pollen samples of T. biroi Friese, indigenous stingless bees from Philippines, were analysed for physicochemical properties and chemical composition. The average chemical main composition showed a relatively narrow range among all samples. Most of determined values met the proposed general quality criteria for bee pollen. The samples contained fructose (4.39 – 9.58 g/100 g), glucose (0.25 – 1.95 g/100 g), sucrose (4.29 – 26.04 g/100 g) and small amounts of di- and trisaccharides; besides sucrose, mannitol (12.66 ± 5.47 g/100 g on average) was highest in concentration among all analysed carbohydrates and sugar alcohols. Furthermore, moderate amounts of soluble proteins and free amino acids were found. The predominant fatty acids were palmitic, α-linolenic and linoleic acids. The major elements quantified were calcium and magnesium. Our results revealed the high nutritive value of T. biroi pollen. The values obtained from this study may serve as basis for standardization of physicochemical requirements and quality parameters for bee pollen from T. biroi.

POTENTIAL ENVIRONMENTAL IMPACTS OF TUNA CAGE FARMING IN THE AEGEAN SEA

The present study aimed to investigate the potential impacts of Atlantic Bluefin Tuna ( Thunnus thynnus ) farming in offshore cage systems in the Aegean Sea (Sigacik Bay-Izmir, Turkey), in respect to physico-chemical water quality parameters, nutrient loads, chlorophyll- a , total suspended solids, zooplankton groups, and TRIX index calculations for the potentially affected cage farm area and an unaffected reference site. Concentrations of physico-chemical variables (temperature, salinity, dissolved oxygen, pH) in the study carried out in May and August 2018, were within the acceptable limits for marine aquaculture in terms of water quality characteristics. The concentrations of PO 4 -P, NH 4 -N, and NO 2 -N showed no temporal or spatial changes, and were recorded below 0.01 mg/L (<0.01) for PO 4 -P and NH 4 -N, whereas lower than 0.005 mg/L (<0.005) for NO 2 -N values in both cage and reference stations in May and August 2018 periods. Results showed low levels of TSS (0.33-11.87 mg/L), both in the cage farm area and the reference site, remaining below the general quality criteria of 30 mg/L for marine environment. No eutrophication risk (TRIX index, T<4 ) was observed around the Tuna Cage Farm Site in Sigacik Bay, according to the legislations enacted for “Sensitive Areas of Enclosed Bays where fish farms are not allowed”. Based on these findings, demonstrating highly interactive trophic level variability, it can be concluded that the impacts of the Tuna Cage Farm were not significant, possibly due to the consistent movement of the water in currents in the study area.

A systematic review on the quality, validity and usefulness of current cost-effectiveness studies for treatments of neovascular age-related macular degeneration.

Ophthalmologists increasingly depend on new drugs to advance their treatment options. These options are limited by restraints on reimbursements for new and expensive drugs. These restraints are put in place through health policy decisions based on cost-effectiveness analyses (CEA). Cost-effectiveness analyses need to be valid and of good quality to support correct decisions to create new treatment opportunities. In this study, we report the quality, validity and usefulness of CEAs for therapies for nAMD. A systematic review in PubMed, EMBASE and Cochrane was performed to include CEAs. Quality and validity assessment was based on current general quality criteria and on elements that are specific to the field of ophthalmology. Forty-eight CEAs were included in the review. Forty-four CEAs did not meet four basic model quality and validity criteria specific to CEAs in the field of ophthalmology (both eyes analysed instead of one; a time horizon extending beyond 4years; extrapolating VA and treatment intervals beyond trial data realistically; and including the costs of low-vision). Four CEAs aligned with the quality and validity criteria. In two of these CEAs bevacizumab as-needed (PRN) was more cost-effective than bevacizumab monthly; aflibercept (VIEW); or ranibizumab monthly or PRN. In two CEAs, ranibizumab (PRN or treat and extent) was dominant over aflibercept. In two other CEAs, aflibercept was either more cost-effective or dominant over ranibizumab monthly or PRN. Two of the CEAs of sufficient quality and validity show that bevacizumab PRN is the most cost-effective treatment. Comparing ranibizumab and aflibercept, either treatment can be more cost-effective depending on the assumptions used for drug prices and treatment frequencies. The majority of the published CEAs are of insufficient quality and validity. They wrongly inform decision-makers at the cost of opportunities for ophthalmologists to treat patients. As such, they may negatively influence overall patient outcomes and societal costs. For future ophthalmic treatments, CEAs need to be improved and only published when they are of sufficient quality and validity.

Assistive technology provision: towards an international framework for assuring availability and accessibility of affordable high-quality assistive technology

Purpose: This is a position paper describing the elements of an international framework for assistive technology provision that could guide the development of policies, systems and service delivery procedures across the world. It describes general requirements, quality criteria and possible approaches that may help to enhance the accessibility of affordable and high quality assistive technology solutions.Materials and methods: The paper is based on the experience of the authors, an analysis of the existing literature and the inputs from many colleagues in the field of assistive technology provision. It includes the results of discussions of an earlier version of the paper during an international conference on the topic in August 2017.Results and conclusion: The paper ends with the recommendation to develop an international standard for assistive technology provision. Such a standard can have a major impact on the accessibility of AT for people with disabilities. The paper outlines some the key elements to be included in a standard.Implications for RehabilitationAssistive technology is a key element in rehabilitation, but many people have no access to affordable AT solutions. The recommendations in the paper aim to inform policies, systems and service delivery procedures on how to improve access to AT across the world.