Bernt Kartman

VALUATION OF HEALTH CHANGES WITH THE CONTINGENT VALUATION METHOD : A TEST OF SCOPE AND QUESTION ORDER EFFECTS

In recent years, there has been a growing interest in the contingent valuation method for measurement of monetary values of various commodities. However, the validity and reliability of the method need to be examined thoroughly. This paper reports results of a test of scope and question order effects in a contingent valuation experiment in the health care field. Using three binary valuation questions, data were collected on willingness to pay for superior treatment of reflux oesophagitis. To test for scope effects, different probabilities of successful short- and long-term treatments were evaluated using a split sample approach. The presence of question order effects was tested by assigning respondents to different question orders. The contingent valuation method proved sensitive to changes in scope in that the willingness to pay increased with the probability of being free from symptoms and with a reduced risk of having a relapse once recovered. Also, regression analysis indicate that people who suffer from severe reflux oesophagitis are more willing to pay for more effective treatment. No question order effects were detected in the data.

A Multinational Investigation of Time and Traveling Costs in Attending Anticoagulation Clinics

OBJECTIVES Anticoagulation is used in patients with atrial fibrillation to reduce the risk of ischemic stroke. The therapy requires regular monitoring and, frequently, dose adjustment. This study aimed to determine the time and traveling costs that patients incur to themselves and society in attending anticoagulation clinics. METHODS A subset of patients from 105 primary and secondary care clinics allocated to the warfarin arm of SPORTIF III (patients from Australia, France, Portugal, Spain, Sweden, and the UK) completed a questionnaire. Patients indicated the type of transport used for clinic visits, and estimated traveling expenses. Patients were also asked to estimate total traveling and clinic attendance time, and to confirm whether they were currently employed and whether they had to give up time from work to attend the clinic. Time cost of companions was also taken into consideration. Cost per visit was calculated (euro, 2003 prices). RESULTS Questionnaires for a total of 381 patients were analyzed, with the majority of patients from Sweden (n = 130) and the UK (n = 101). Mean cost to patients varied widely between countries, ranging from euro6.9 (France) to euro20.5 (Portugal) per visit. For most countries, time costs (value of lost working and leisure time) were the main driver of costs. Mean time cost to society ranged from euro5.6 (France) to euro31.7 (Portugal) per visit. CONCLUSIONS Patients incur considerable costs when visiting anticoagulation clinics, and these costs vary by country. The results suggest the importance of taking a broad economic perspective when considering the cost-effectiveness of warfarin.

Health State Utilities in Gastroesophageal Reflux Disease Patients with Heartburn: A Study in Germany and Sweden

The objectives of this study were to assess health state utilities in patients with gastroesophageal reflux disease with heartburn and to analyze if severity and annual frequency of heartburn can predict utilities. Atotal of 1011 patients in Germany and Sweden participated in telephone interviews, where utilities were assessed using the rating scale (RS), EQ-5D, time trade-off (TTO) and standard gamble (SG) instruments. The average RS, EQ-5D, TTO, and SG utilities were 0.69, 0.70, 0.88, and 0.89, respectively. Linear regression analyses showed that the EQ-5D and RS utilities were negativelyand significantly related to the severity and frequency of heartburn. The EQ-5D and RS results indicate that patients with heartburn assign their health states substantial disutility and that it is feasible to estimate regression equations to predict utilities from heartburn-specific variables. In the TTO and SGanalyses, the impact of heartburnwas in the expected direction but smaller and in general not significant.

The Cost of Angina Pectoris in Sweden

SummaryA survey of 402 Swedish patients with angina pectoris was performed to estimate the annual direct medical costs, and nonmedical costs, of a typical Swedish angina pectoris patient. and to identify those variables having the greatest impact on the direct medical costs. Data regarding the consumption of health care services over a 3-month period were collected through telephone interviews conducted by trained nurses at a medical marketing agency. The data were multiplied by 4 to obtain an estimate of the annual resource consumption.The annual direct medical cost of angina pectoris was estimated at 40 052 Swedish kronor (SEK;

Contingent valuation with an open-ended follow-up question: a test of scope effects

US1 ≈ SEK7.20, March 1995) per patient, comparable with the cost of a myocardial infarction. As expected, however, the severity of angina pectoris was important in determining the direct medical cost. The significant variables explaining variations in direct costs were (in order of importance): (i) whether the patient had undergone cardiovascular surgery; (ii) whether the patient was treated by a general practitioner or an imernist; (iii) the number of years since first diagnosis of angina pectoris: and (iv) whether the patient’s angina pectoris was characterised as stable or unstable. The annual nonmedical cost of angina pectoris per patient was estimated at SEK38 225. The relatively high costs of angina pectoris underline the importance of health economic evaluations of various diseases and medical interventions.

Cost-effectiveness of felodipine-metoprolol (Logimax) and enalapril in the treatment of hypertension.

It has been suggested that an open-ended follow-up question should be added to the binary contingent valuation question. Before this is generally recommended, it is important to evaluate the properties of such follow-up questions. Using a split sample approach, we test whether the open-ended follow-up is sensitive to the scope of the commodity being valued. No significant scope effects were detected. It is concluded that the results obtained do not support the use of an open-ended follow-up in contingent valuation applications.

Multivariate Prediction Equations for HbA1c Lowering, Weight Change, and Hypoglycemic Events Associated with Insulin Rescue Medication in Type 2 Diabetes Mellitus: Informing Economic Modeling

We present results from a Swedish retrospective cost-effectiveness analysis of felodipine-metoprolol (Logimax) and enalapril in hypertension. In the 8-week trial, the average reduction of diastolic blood pressure (DBP) and the share of patients reaching target DBP were both significantly greater in the felodipine-metoprolol group. Cost of treatment (costs of drugs and physician visits) was somewhat higher in the felodipine-metoprolol group. After 8 weeks, an extra 4.8 mmHg reduction and an additional 22% of patients reaching target DBP were achieved with felodipine-metoprolol at the extra cost of SEK 19 (Swedish kronor,

Exenatide Once Weekly Plus Metformin for the Treatment of Type 2 Diabetes Mellitus: A Network Meta-Analysis of Randomised Controlled Trials

US I=SEK 7.90). The incremental cost per mmHg reduction and per patient reaching target DBP was calculated at SEK 4 and SEK 86, respectively. Average cost-effectiveness ratios showed that the costs per mmHg reduction and per patient reaching target DBP after 8 weeks were 40 and 34% lower in the felodipine-metoprolol group, respectively. In conclusion, felodipine-metoprolol is cost-effective in the treatment of hypertension.

Willingness to Pay for Reductions in Angina Pectoris Attacks

BACKGROUND Type 2 diabetes mellitus (T2DM) is chronic and progressive and the cost-effectiveness of new treatment interventions must be established over long time horizons. Given the limited durability of drugs, assumptions regarding downstream rescue medication can drive results. Especially for insulin, for which treatment effects and adverse events are known to depend on patient characteristics, this can be problematic for health economic evaluation involving modeling. OBJECTIVES To estimate parsimonious multivariate equations of treatment effects and hypoglycemic event risks for use in parameterizing insulin rescue therapy in model-based cost-effectiveness analysis. METHODS Clinical evidence for insulin use in T2DM was identified in PubMed and from published reviews and meta-analyses. Study and patient characteristics and treatment effects and adverse event rates were extracted and the data used to estimate parsimonious treatment effect and hypoglycemic event risk equations using multivariate regression analysis. RESULTS Data from 91 studies featuring 171 usable study arms were identified, mostly for premix and basal insulin types. Multivariate prediction equations for glycated hemoglobin A1c lowering and weight change were estimated separately for insulin-naive and insulin-experienced patients. Goodness of fit (R2) for both outcomes were generally good, ranging from 0.44 to 0.84. Multivariate prediction equations for symptomatic, nocturnal, and severe hypoglycemic events were also estimated, though considerable heterogeneity in definitions limits their usefulness. CONCLUSIONS Parsimonious and robust multivariate prediction equations were estimated for glycated hemoglobin A1c and weight change, separately for insulin-naive and insulin-experienced patients. Using these in economic simulation modeling in T2DM can improve realism and flexibility in modeling insulin rescue medication.

A Network Meta-analysis Comparing Exenatide Once Weekly with Other GLP-1 Receptor Agonists for the Treatment of Type 2 Diabetes Mellitus

Table 1. Relative effect sizes for change of HbA1c, risk of nausea and treatment discontinuation due to AEs, all GLP-1 RA treatments compared to placebo. • In addition to GLP-1 RAs, two sulfonylureas (glibenclamide, glimepiride), two thiazolidinediones (rosiglitazone, pioglitazone) the dipeptidyl peptidase-4 inhibitor sitagliptin and insulin were included to ensure a connected network of comparative trials when direct evidence was not available. Results are presented only for GLP1RAs.