Multiattribute and single-attribute utility functions for the health utilities index mark 3 system

BACKGROUND

The Health Utilities Index Mark 3 (HUI3) is a generic multiattribute preference-based measure of health status and health-related quality of life that is widely used as an outcome measure in clinical studies, in population health surveys, in the estimation of quality-adjusted life years, and in economic evaluations. HUI3 consists of eight attributes (or dimensions) of health status: vision, hearing, speech, ambulation, dexterity, emotion, cognition, and pain with 5 or 6 levels per attribute, varying from highly impaired to normal.

OBJECTIVES

The objectives are to present a multiattribute utility function and eight single-attribute utility functions for the HUI3 system based on community preferences.

STUDY DESIGN

Two preference surveys were conducted. One, the modeling survey, collected preference scores for the estimation of the utility functions. The other, the direct survey, provided independent scores to assess the predictive validity of the utility functions.

MEASURES

Preference measures included value scores obtained on the Feeling Thermometer and standard gamble utility scores obtained using the Chance Board.

RESPONDENTS

A random sample of the general population (> or =16 years of age) in Hamilton, Ontario, Canada.

RESULTS

Estimates were obtained for eight single-attribute utility functions and an overall multiattribute utility function. The intraclass correlation coefficient between directly measured utility scores and scores generated by the multiattribute function for 73 health states was 0.88.

CONCLUSIONS

The HUI3 scoring function has strong theoretical and empirical foundations. It performs well in predicting directly measured scores. The HUI3 system provides a practical way to obtain utility scores based on community preferences.

The development and use of quality-of-life measures to evaluate health outcomes in Japan

Health outcomes measurement forms a key aspect of data collection for economic evaluations. Quality-of-life instruments provide a measure of patient-focused health outcomes. Such instruments, including the EuroQoL questionnaire (EQ-5D) and the Short-form 36 (SF-36) are already being used in Japan. Utility instruments provide an alternative way of measuring quality of life for use in economic analyses. At present, utility measurement in Japan is limited to scores derived from the EQ-5D. Although the SF-36 was designed as a health profile measure, it has since been tested for use as a utility measure, with valuation of items now being undertaken in Japan. Utility measurement in Japan is likely to be advanced further by the validation and introduction of the Health Utilities Index. The experiences of other countries provide the opportunity for Japan to learn how utility scores may be used in cost-utility analyses of healthcare technologies.

Why has the use of health economic evaluation in Japan lagged behind that in other developed countries?

The aging population and the increasing availability of new medical technologies, particularly pharmaceuticals, have led to growing pressure on governments worldwide to contain healthcare costs. Increasingly, economic evaluation is used to aid decisions on the reimbursement and formulary access of drugs, and pharmaceutical companies are often required to demonstrate the cost effectiveness of their products. Canada and the UK are examples of countries that have successfully incorporated mandatory requirements for economic evaluations into the decision-making process in healthcare. Japan faces cost-containment issues for its health and welfare system similar to those seen elsewhere in the world. Despite this, economic assessments are not currently used in the allocation of drug budgets. Reasons why economic evaluations for healthcare have not yet been used routinely in Japan include governmental approaches to healthcare cost containment, the pricing of pharmaceuticals, the organisation of the healthcare system, attitudes of the medical profession, and limited knowledge and expertise. However, small but encouraging steps are now being taken towards the introduction of economic evaluations in Japanese medicine.

Information barriers to the implementation of economic evaluations in Japan

With increasing cost-containment pressures within healthcare systems worldwide, economic evaluations of medical technologies, particularly pharmaceuticals, are used to aid the allocation of expenditure and resources. Facing similar pressures, Japan will probably also introduce economic evaluation of health technology. However, the structure of the healthcare system in Japan does not lend itself naturally to the collection of the epidemiological and cost data required for economic evaluations in medicine. In addition, there are no formal methodological guidelines in place for these analyses. To overcome these information barriers in Japan, progress may be aided by the adoption of approaches used in other countries for data collection and guideline development.

Cost-effectiveness of Apligraf in the treatment of venous leg ulcers

Venous ulcers are the most common chronic wounds of the lower leg. Skin substitutes recently have been introduced to stimulate nonhealing wounds. To conduct an incremental cost-effectiveness analysis, a model was developed to compare the four-layer bandage system, with and without one application of skin substitute, for the outpatient treatment of venous leg ulcers. The model estimated the costs and consequences of treatment with and without the skin substitute application. Two analytic horizons were explored: 3 months and 6 months. Determined by seven physicians, data and assumptions for the 3-month model were based on information from a clinical trial, published studies, and clinical experience. Data for the 6-month model were extrapolated from the shorter model. The model results indicate that over 3 months, the use of the skin substitute provided a benefit of 22 ulcer days averted per patient at an incremental cost of $304 (societal). The incremental cost-effectiveness ratio was $14 per ulcer day averted. Over 6 months, the incremental cost-effectiveness ratio was less than $5 per ulcer-day averted. The skin substitute plus a four-layer bandage was more costly and more effective than the four-layer bandage alone. The skin substitute is increasingly cost-effective over a longer analytic horizon and in a subgroup of patients with ulcers of long duration (greater than 1-year duration at baseline). The results come from a model that is based on a series of estimates and assumptions, and accordingly, confirmation of this finding in a prospective study is encouraged.

Visual analog scales: do they have a role in the measurement of preferences for health states?

Visual analog scales (VASs) have long been used as a method of measuring preferences for health outcomes. They are easy and inexpensive to implement, can be administered quickly, and lend themselves to self-completion. Over time, however, disturbing questions have emerged concerning the validity of the VAS approach. This article reviews briefly the history, theory, practice, problems, and advantages of VASs; presents some suggestions to improve the validity of VASs; and recommends a limited but useful role for VASs in the process of measuring preferences for health states.

The Health Utilities Index (HUI) system for assessing health-related quality of life in clinical studies

This paper reviews the Health Utilities Index (HUI) systems as means to describe health status and obtain utility scores reflecting health-related quality of life (HRQoL). The HUI Mark 2 (HUI2) and Mark 3 (HUI3) classification and scoring systems are described. The methods used to estimate multiattribute utility functions for HUI2 and HUI3 are reviewed. The use of HUI in clinical studies for a wide variety of conditions in a large number of countries is illustrated. HUI provides a comprehensive description of the health status of subjects in clinical studies. HUI has been shown to be a reliable, responsive and valid measure in a wide variety of clinical studies. Utility scores provide an overall assessment of the HRQoL of patients. Utility scores are also useful in cost-utility analyses and related studies. General population norm data are available. The widespread use of HUI facilitates the interpretation of results and permits comparisons. HUI is a useful tool for assessing health status and HRQoL in clinical studies.

What should be reported in a methods section on utility assessment?

BACKGROUND

The measurement of utilities, or preferences, for health states may be affected by the technique used. Unfortunately, in papers reporting utilities, it is often difficult to infer how the utility measurement was carried out.

PURPOSE

To present a list of components that, when described, provide sufficient detail of the utility assessment.

METHODS

An initial list was prepared by one of the authors. A panel of 8 experts was formed to add additional components. The components were drawn from 6 clusters that focus on the design of the study, the administration procedure, the health state descriptions, the description of the utility assessment method, the description of the indifference procedure, and the use of visual aids or software programs. The list was updated and redistributed among a total of 14 experts, and the components were judged for their importance of being mentioned in a Methods section.

RESULTS

More than 40 components were generated. Ten components were identified as necessary to include even in an article not focusing on utility measurement: how utility questions were administered, how health states were described, which utility assessment method(s) was used, the response and completion rates, specification of the duration of the health states, which software program (if any) was used, the description of the worst health state (lower anchor of the scale), whether a matching or choice indifference search procedure was used, when the assessment was conducted relative to treatment, and which (if any) visual aids were used. The interjudge reliability was satisfactory (Cronbach's alpha = 0.85).

DISCUSSION

The list of components important for utility papers may be used in various ways, for instance, as a checklist while writing, reviewing, or reading a Methods section or while designing experiments. Guidelines are provided for a few components.

Cost-utility analysis in depression: the McSad utility measure for depression health states

Cost-utility analysis, used increasingly over the past decade to analyze costs and effects in treating physical diseases, has received little attention in psychiatry. This article briefly introduces the concepts and methods of utility measurement and illustrates it using depression as an example. The authors describe the McSad health state classification system for depression, a direct utility measure for depression, and report results of an application of McSad among 105 patients who had a recent history of depression. Utility measures express patient preferences for specific health states on a scale ranging from 0, representing death, to 1, representing perfect health. These scores provide the weights used to calculate the number of quality-adjusted life-years gained by an intervention or service. McSad allows a patient's depression health state to be classified according to level of functioning in six dimensions of depression and to be compared with other hypothetical depression health states in order to produce utility scores indicating the patient's relative preferences.

Cost and health related quality of life consequences of multiple sclerosis

OBJECTIVES

To (i) quantify the cost of multiple sclerosis (MS) to the Canadian health care system and society; (ii) measure health utility in MS patients, and (iii) examine the influence of disability on patient utility and health care costs.

MATERIALS AND METHODS

A comprehensive patient survey and chart review of relapsing MS patients in remission, relapse and recalling a relapse.

RESULTS

Annual remission costs increased with EDSS level ($7596 at EDSS 1, $33 206 at EDSS 6). At all EDSS levels the largest costs were due to inability to work, which increased with EDSS. The average relapse cost for all EDSS levels was $1367. An inverse correlation was found between EDSS level and patient utility for patients in remission and relapse. The decrease in remission health utility from EDSS 1 to 6 was 0.24, which is 25% greater than the difference in health status between an average 25 and 85 year-old.

CONCLUSIONS

This study demonstrates that MS produces substantial health care costs and reductions in patient quality of life and ability to work, losses that can be avoided or delayed if disease progression is slowed. These data provide health-care decision-makers with the opportunity to consider the full impact of MS when faced with budget allocation decisions.

Development and testing of a utility measure for major, unipolar depression (McSad)

OBJECTIVE

To develop and test a direct utility measure (McSad) for major, unipolar depression.

METHODS

A depression specific, multi-attribute health state classification system was created; clinical validity was evaluated by experts using specially designed structured exercises; a cross-sectional survey was conducted to obtain directly measured utilities for depression health states.

SETTING

Tertiary care, university medical centre.

PARTICIPANTS

Three psychiatrists, 3 psychiatric nurses and 3 social workers assessed depression health state clinical validity. Survey participants were referred by psychiatrists and consisted of 105 outpatients, currently in remission with at least one episode of major, unipolar depression in the past two years.

SURVEY RESULTS

Respondent self-health state utility (mean and 95% confidence interval (CI)) was 0.79 (0.74-0.83). Utilities for hypothetical, untreated depression health states were: mild depression, 0.59 (0.55-0.62); moderate depression, 0.32 (0.29-0.34); severe depression, 0.04 (0.01-0.07). Fifty-six percent of respondents rated severe depression worse than being dead. Utilities for the hypothetical health states were not correlated with self-health utility. The intra-class correlation coefficient (ICC) was satisfactory for 13 of the 14 health states assessed.

CONCLUSIONS

McSad was feasible and acceptable in patients with a history of major unipolar depression. The utilities for mild, moderate and severe untreated depression show the low health-related quality of life associated with depression. Initial assessments of test-retest reliability and validity yielded satisfactory results but further studies are needed to extend our knowledge of the measurement properties of McSad.

The revised Canadian Guidelines for the Economic Evaluation of Pharmaceuticals

The first edition of the Guidelines for Economic Evaluation of Pharmaceuticals: Canada was published in November 1994. At that time, the Canadian Coordinating Office for Health Technology Assessment (CCOHTA) was assigned the task of maintaining and regularly updating the Canadian Guidelines. Since their introduction, a great deal of experience has been gained with the practical application of the guidelines. Their role has also evolved over time, from being a framework for pharmacoeconomic research to the point where a wide variety of decision-makers use economic evaluations based on the principles set out in the guidelines as a means of facilitating their formulary decisions. In addition, methodologies in certain areas (and the body of related research literature in general) have developed considerably over time. Given these changes in the science and the experience gained, CCOHTA convened a multi-disciplinary committee to address the need for revisions to the guidelines. The underlying principles of the review process were to keep the guidance nature of the document, to focus on the needs of 'doers' (so as to meet the information needs of 'users') and to provide information and advice in areas of controversy, with sound direction in areas of general agreement. The purpose of this review is three-fold: (i) to outline the process which lead to the revision of the Canadian Guidelines; (ii) to describe the major changes made to the second edition of this document; and (iii) to consider the 'next steps' as they relate to the impact of such guidelines and the measurement of outcomes related to economic assessments of pharmaceuticals in general.

Cost effectiveness of multi-therapy treatment strategies in the prevention of vertebral fractures in postmenopausal women with osteoporosis

OBJECTIVE

The aim of this study was to evaluate the cost effectiveness of multi-therapy treatment strategies in the prevention of vertebral fractures in postmenopausal women with osteoporosis.

DESIGN

A retrospective, incremental cost-effectiveness analysis was conducted from a societal perspective. It compared 9 treatment strategies over 3 years and incorporated the willingness of patients to initiate and continue each therapy.

MAIN OUTCOME MEASURES AND RESULTS

Four nondominated strategies formed the efficient frontier in the following order: (i) calcium-->no therapy; (ii) ovarian hormone therapy (OHT)-->calcium-->no therapy [166 Canadian dollars ($Can)]; (iii) OHT-->etidronate-->calcium-->no therapy ($Can2331); and (iv) OHT-->alendronate-->calcium-->no therapy ($Can40,965). The figures in parentheses are the incremental costs per vertebral fracture averted to move to that strategy from the previous strategy for patients who had undergone a hysterectomy.

CONCLUSIONS

We identified 4 efficient multi-therapy strategies for the treatment of vertebral osteoporosis in postmenopausal women, 2 of which were consistent with the practice guidelines of the Osteoporosis Society of Canada. Decision-makers may select from among these efficient strategies on the basis of incremental cost effectiveness.

Assessing the value of a new pharmaceutical. A feasibility study of contingent valuation in managed care

OBJECTIVES

The authors assessed the feasibility and construct validity of the contingent valuation method for measuring the monetary value to healthy enrollees in a health maintenance organization of a new drug, filgrastim, as prophylaxis against febrile neutropenia after chemotherapy treatment for cancer.

METHODS

A random sample of 220 enrollees from a closed-panel staff-model health maintenance organization who did not have cancer were interviewed. Chemotherapy, febrile neutropenia and filgrastim were described by video and decision board. Questions were asked in two different scenarios: (1) User-based: Assuming they were at the point of consumption and about to receive chemotherapy, what is the maximum they would be willing to pay to receive filgrastim? and (2) Insurance-based: Given they were at risk of cancer in the future, what is the maximum they would be willing to pay in additional monthly insurance premiums to add filgrastim to the plan? In a second insurance scenario where respondents were told that filgrastim was covered, what is the minimum reduction in premium that persons were willing to accept to relinquish coverage of the drug? A 2 x 2 factorial design was used to contrast two bidding algorithms to test for starting point bias and two 5-yearly prior risks of cancer, 1/200 versus 1/100. Main effects were tested by ANCOVA controlling for age, sex, health, and income.

RESULTS

Demographics of experimental cells were similar. No evidence was found of significant starting point bias. For user-based questions, as expected, willingness-to-pay increases with febrile neutropenia risk reduction, but at a declining marginal rate. Despite careful presentation of information to respondents, willingness-to-pay for insurance was higher in the lower prior risk group. Consistent with previous contingent valuation studies, the authors of the present study found evidence that willingness-to-accept exceeds willingness-to-pay for coverage of the same benefit.

CONCLUSIONS

An insurance-based contingent valuation study is feasible in a health maintenance organization. Construct validation evidence was encouraging, with the exception of the test for prior risk of cancer; however, this was a between-person contrast and may have been confounded by other factors.

Health state utilities in knee replacement surgery: the development and evaluation of McKnee

OBJECTIVE

1. To develop McKnee, a classification system and direct utility measure for health states associated with knee replacement (KR) surgery. 2. To apply McKnee in a before-after study of KR surgery to: (i) gain experience with McKnee in an elderly population; (ii) confirm the practicality and usefulness of the McKnee system; (iii) assess self-health utility one week before and 3 mo after surgery; (iv) evaluate the stability of 3 clinical marker health states describing mild, moderate, and severe knee disability; (v) compare self-health utility scores with Short Form 36 (SF-36).

METHODS

1. Instrument development: The McKnee modified Health Utilities Index was developed and used to describe self-health and clinical marker health states: the clinical validity of the clinical marker states was evaluated by 5 clinicians involved in the care off KR patients. 2. Instrument evaluation: McKnee and the SF-36 were administered to 48 patients with osteoarthritis one week before and 3 mo after KR surgery.

RESULTS

Before-after study: McKnee was feasible and acceptable in the older patient group studied (mean age in years, SD: 69.9, 8.6). No change in self-health utility (mean, SD) was observed at 3 mo postsurgery: before -0.78, 0.17; after -0.78, 0.21. On the SF-36, only the change scores for pain and health transition were statistically significant. Utilities (mean, SD) for the clinical marker health states were: mild -0.80, 0.20; moderate -0.55, 0.28; and severe -0.48, 0.31. The clinical marker mean utility scores were stable between the baseline and 3 mo assessment, but the intraclass correlation coefficients for individual scores were low.

CONCLUSION

McKnee provides a preference based measure of health related quality of life that can be used to obtain and interpret clinically the knee disability utility scorers needed for cost-utility studies and medical decision-making models about KR surgery. The McKnee system provides a practical and useful method for classifying knee disability health states and obtaining direct measurements of utility scores for selected health states.

Preferences for health outcomes and cost-utility analysis

Economic evaluation of health programs consists of the comparative analysis of alternative courses of action in terms of both costs and consequences. The five analytic techniques are cost-consequence analysis, cost-minimization analysis, cost-effectiveness analysis, cost-utility analysis, and cost-benefit analysis. Although all techniques have the same objective of informing decision making in the health programs, they come from different theoretic backgrounds and relate differently to the discipline of economics. Cost-utility analysis formally incorporates the measured preferences of individuals for the health outcome consequences of the alternative programs. The individuals may be actual patients who are experiencing or have experienced the outcomes, or they may be a representative sample of the community, many of whom may someday face the outcomes. The health outcomes, at the most general level, consist of changes in the quantity and quality of life; that is, changes in mortality and morbidity. Changes in quantity of life are measured with mortality; changes in quality of life are measured with health-related quality-of-life instruments. Utilities represent a particular approach to the measurement of health-related quality of life that is founded on a well specified theory and provides an interval scale metric. Changes in quantity of life, as measured in years, can be combined with changes in quality of life, as measured in utilities, to determine the number of quality-adjusted life years gained by a particular health program. This can be compared with the incremental cost of the program to determine the cost per quality-adjusted life-year gained. Utilities may be measured directly on patients or other respondents by means of techniques such as visual analog scaling, standard gamble, or time trade-off. Utilities may be determined indirectly by means of a preference-weighted multi-attribute health status classification system such as the health utilities index. The health utilities index is actually a complete system for use in studies. It consists of questionnaires in various formats and languages, scoring manuals, and descriptive health status classification systems. The health utilities index is useful in clinical studies and in population health surveys, as well as in cost-utility analyses.

Guidelines for pharmacoeconomic studies. Recommendations from the panel on cost effectiveness in health and medicine. Panel on cost Effectiveness in Health and Medicine

This article reports the recommendations of the Panel on Cost Effectiveness in Health and Medicine, sponsored by the US Public Health Service, on standardised methods for conducting cost-effectiveness analyses. Although not expressly directed at analyses of pharmaceutical agents, the Panel's recommendations are relevant to pharmacoeconomic studies. The Panel outlines a 'Reference Case' set of methodological practices to improve quality and comparability of analyses. Designed for studies that inform resource-allocation decisions, the Reference Case includes recommendations for study framing and scope, components of the numerator and denominator of cost-effectiveness ratios, discounting, handling uncertainty and reporting. The Reference Case analysis is conducted from the societal perspective, and includes all effects of interventions on resource use and health. Resource use includes 'time' resources, such as for caregiving or undergoing an intervention. The quality-adjusted life-year (QALY) is the common measure of health effect across Reference Case studies. Although the Panel does not endorse a measure for obtaining quality-of-life weights, several recommendations address the QALY. The Panel recommends a 3% discount rate for costs and health effects. Pharmacoeconomic studies have burgeoned in recent years. The Reference Case analysis will improve study quality and usability, and permit comparison of pharmaceuticals with other health interventions.

Multiattribute utility function for a comprehensive health status classification system. Health Utilities Index Mark 2

The Health Utilities Index Mark 2 (HUI:2) is a generic multiattribute, preference-based system for assessing health-related quality of life. Health Utilities Index Mark 2 consists of two components: a seven-attribute health status classification system and a scoring formula. The seven attributes are sensation, mobility, emotion, cognition, self-care, pain, and fertility. A random sample of general population parents were interviewed to determine cardinal preferences for the health states in the system. The health states were defined as lasting for a 60-year lifetime, starting at age 10. Values were measured using visual analogue scaling. Utilities were measured using a standard gamble technique. A scoring formula is provided, based on a multiplicative multiattribute utility function from the responses of 194 subjects. The utility scores are death-anchored (death = 0.0) and form an interval scale. Health Utilities Index Mark 2 and its utility scores can be useful to other researchers in a wide variety of settings who wish to document health status and assign preference scores.

Canadian guidelines for economic evaluation of pharmaceuticals. Canadian Collaborative Workshop for Pharmacoeconomics

In 1994, Canada became the second country to release national guidelines for the economic evaluation of pharmaceuticals. The guidelines were developed over a period of 18 months through an elaborate process of broad consultation with a wide variety of relevant stakeholders. The intent of the guidelines is to provide guidance to doers and users of studies, by laying out the general 'state of the art' regarding methods, and by providing specific methodological advice on many matters. The aim is to improve the scientific quality and integrity of studies, and to enhance consistency and comparability across studies. This article presents the Canadian guidelines, both in summary and in detail. Because the techniques of economic evaluation are widely applicable beyond pharmaceuticals, the guidelines will be of interest to researchers and decision makers in all fields of healthcare. Because the methods are not country specific, the guidelines will be of interest to those in other countries as well as in Canada.

Multi-attribute health status classification systems. Health Utilities Index

In this article, multi-attribute approaches to the assessment of health status are reviewed with a special focus on 2 recently developed systems, the Health Utilities Index (HUI) Mark II and Mark III systems. The Mark II system consists of 7 attributes: sensation, mobility, emotion, cognition, self-care, pain and fertility. The Mark III system contains 8 attributes: vision, hearing, speech, ambulation, dexterity, emotion, cognition and pain. Each attribute consists of multiple levels of functioning. A combination of levels across the attributes constitutes a health state. The HUI systems are deliberately focused on the fundamental core attributes of health status, and on the capacity of individuals to function with respect to these attributes. Thus, the measure obtained constitutes a pure description of health status, uncontaminated by differential opportunity or preference. Multi-attribute systems provide a compact but comprehensive framework for describing health status for use in population health and programme evaluation studies. An important advantage of such systems is their ability to simultaneously provide detail on an attribute-by-attribute basis and to capture combinations of deficits among attributes. An additional advantage is their compatibility with multi-attribute preference functions, which provide a method for computing a summary health-related quality-of-life score for each health state.

Reliability of the Health Utilities Index--Mark III used in the 1991 cycle 6 Canadian General Social Survey Health Questionnaire

This study presents information on the test-retest reliability of the Health Utility Index--Mark III (HUI) system used in cycle 6 of the Canadian General Social Survey (GSS). The HUI system used in this reliability study consists of an eight-attribute health status classification system (HSCS) and a function for generating a summary score of health-related quality of life. To estimate test-retest reliability, a stratified random sample of individuals (n = 506) completing GSS telephone interviews during August and September, 1991 were interviewed again 1 month later. Weighting adjustments based on the probability of selection were invoked during the analyses to provide unbiased estimates of test-retest reliability for all GSS respondents in the August-September period. The results indicate that the individual questions, attributes and provisional index scores generally provided reliable information on health status in the GSS. The exceptions to this were limitations in speech and dexterity which were reported very infrequently. Kappa estimates of test-retest reliability for individual questions varied from 0.184 to 0.766. For the eight attributes, kappa estimates varied from 0.137 to 0.728. Using the provisional index scores to quantify health overall, a test-retest reliability of 0.767 was obtained (intra-class correlation coefficient).

Multi-attribute preference functions. Health Utilities Index

Multi-attribute utility theory, an extension of conventional utility theory, can be applied to model preference scores for health states defined by multi-attribute health status classification systems. The type of preference independence among the attributes determines the type of preference function required: additive, multiplicative or multilinear. In addition, the type of measurement instrument used determines the type of preference score obtained: value or utility. Multi-attribute utility theory has been applied to 2 recently developed multi-attribute health status classification systems, the Health Utilities Index (HUI) Mark II and Mark III systems. Results are presented for the Mark II system, and ongoing research is described for the Mark III system. The theory is also discussed in the context of other well known multi-attribute systems. The HUI system is an efficient method of determining a general public-based utility score for a specified health outcome or for the health status of an individual. In clinical populations, the scores can be used to provide a single summary measure of health-related quality of life. In cost-utility analyses, the scores can be used as quality weights for calculating quality-adjusted life years. In general populations, the measure can be used as quality weights for determining population health expectancy.

A study to determine the efficacy and safety of tenoxicam versus piroxicam, diclofenac and indomethacin in patients with osteoarthritis: a meta-analysis

OBJECTIVE

To obtain a better quantitative and qualitative estimate of the effect of tenoxicam (Tx) compared to piroxicam (Px), diclofenac (Dcl) and indomethacin (Ind) in the treatment of osteoarthritis (OA).

METHODS

Relevant studies were identified using computerized Medline search, manual search of cited references and correspondence with investigators, colleagues and the manufacturer of Tx. Once the studies were selected and chosen on the basis of predetermined methodologic criteria, the required data were extracted by 2 authors, independently. Eighteen studies met the required eligibility criteria. Meta-analyses were undertaken on 12 studies of Tx vs Px, 3 studies of Tx vs Dcl, and 2 studies of Tx vs Ind. Efficacy was measured in 2 ways: (1) physician global rating scale and (2) pain scale. Safety was measured in 3 ways: (1) physician global rating scale, (2) number of patients with adverse events, and (3) dropouts due to adverse events.

RESULTS

The following findings of the meta-analysis were statistically significant: In Tx vs Px comparisons, efficacy-(1), safety-(1) and safety-(3) were all better with Tx; in Tx vs Ind comparisons, safety-(1) and safety-(2) were better with Tx. All other findings showed no statistically significant differences between Tx and the comparison drug.

CONCLUSIONS

Compared to Px, Tx performs better on physician assessment of efficacy and tolerability, but the other comparisons remain inconclusive. Compared to Dcl, there appears not to be a difference. Compared to Ind, Tx is safer.