Biomedical subjects

B A van Hout

Publications and source records attributed to B A van Hout.

At least 19 recordsLinked to original sources

PubMed2003

Meta-analysis: comparing the efficacy of proton pump inhibitors in short-term use.

BACKGROUND: Proton pump inhibitors have a prominent role in the management of acid-related diseases. Controlling expenses on proton pump inhibitors would yield great economic benefits for Dutch health care. AIM: To investigate whether clinical differences in proton pump inhibitors exist. METHODS: We searched Medline, EMBASE and the Cochrane Library. We identified papers in English, German, French or Dutch in which two or more proton pump inhibitors were compared under the same clinical conditions in gastro-oesophageal reflux disease, peptic ulcer disease or Helicobacter pylori eradication. The pooled relative risks were calculated using the Mantel-Haenszel method. RESULTS: Two significant differences were found in the proton pump inhibitors compared. In gastro-oesophageal reflux disease, esomeprazole 40 mg was superior to omeprazole 20 mg (relative risk, 1.18; 95% confidence interval, 1.14-1.23). In peptic ulcer disease, pantoprazole 40 mg was superior to omeprazole 20 mg (relative risk, 1.07; 95% confidence interval, 1.02-1.13). In Helicobacter pylori eradication, no significant differences were found. CONCLUSIONS: Both significant differences found were in favour of the highest dose of proton pump inhibitor on a milligram basis. This indicates that the difference may be dose dependent and not proton pump inhibitor specific. Therefore, when prescribing proton pump inhibitors, arguments other than clinical efficacy, such as those related to pharmaco-economics, may be considered.

Administration, Oral↗

PubMed2003

Design of the Dutch prevention of influenza, surveillance and management (PRISMA) study.

Rationale and design of a study on the cost-effectiveness of the Dutch influenza vaccination campaign are described. During two influenza epidemics, about 75,000 primary care patients recommended for influenza vaccination are included. Cases have fatal or non-fatal influenza, pneumonia, otitis media, acute respiratory disease (ARD), heart failure, myocardial infarction, depression or diabetes dysregulation. Per case four controls are sampled, frequency matched on age and high-risk co-morbidity (<18 years, 18-64, >/=65 healthy, >/=65 with co-morbidity). Baseline and outcome data are retrieved from patient records. During the 1999-2000 influenza A epidemic 5891 (7.9%) high-risk children, 24,848 (33.2%) high-risk adults aged 18-64 years, 18,484 (24.7%) elderly with co-morbidity and 25,527 (34.1%) healthy elderly had been included. The mortality rate was 5.2 per 1000 and 2035 non-fatal outcome events were recorded (incidence rate 27.2/1000).

Adolescent↗

PubMed2003

Quality of life and NYHA class 30 years after mechanical aortic valve replacement.

OBJECTIVE: (1) To evaluate the quality of life (QoL) scores, assessed with SF36 and EuroQol (EQ-5D), of long term survivors after mechanical aortic valve replacement (mAVR); (2) to study the association of QoL with NYHA score, number of major bleeding and thrombo-embolic events and follow-up time; (3) to compare QoL scores of long term mAVR survivors with QoL scores of other populations. METHODS: In total 312 patients had a mAVR between 1964 and 1974 at St. Antonius Hospital Nieuwegein (NL). Mean age at operation was 41 (sd=12). Mean postoperative NYHA class at 1-year follow-up was 1.7 (sd=0.7). In 2001 the survivors (n=78; 25%) were followed-up for late events, NYHA class and QoL scores. 69 patients (93%) returned completed questionnaires. RESULTS: Mean duration of follow-up was 30 years (sd=1.8). Mean age of responders was 65 years (sd=10, range 47-93). In 2001, NYHA class of responders was 2 (sd=0.9). The mean (sd) SF36 scores for responders were: 64 (29) for physical function, 64 (29) for role-physical, 80 (30) for bodily pain, 55 (25) for general health, 63 (23) for vitality, 73 (29) for social functioning, 70 (38) for role-emotional, 76 (18) for mental health. The mean EQ-5D score of responders was: 61 (13). These SF36 and EQ-5D scores are comparable to those of other populations (e.g. cancer, diabetes type-2, migraine, chronic liver disease and iliac artery occlusive disease and Dutch general population). For responders a moderate to high association of SF36 and EQ-5D scores and their NYHA scores (R2=0.36) was found. The number of major bleeding events, age, sex and survival time were not related to QoL. CONCLUSION: At long term follow-up (mean 30 years) of patients who had mAVR, QoL was relatively high; it was moderately to highly associated with their NYHA class; bleeding and thromboembolic events seem to be of little importance for the QoL at long term follow-up. QoL at long term follow-up of patients who had mAVR is comparable to other cross sectional designed studies with short term follow-up and other population.

Adult↗

PubMed2002

Association between joint bleeds and Pettersson scores in severe haemophilia.

PURPOSE: To assess and quantify the association of haemophilic arthropathy, measured by the radiological Pettersson score, with the number of joint bleeds suffered by the patient. MATERIAL AND METHODS: In order to quantify the effect of the cumulative number of joint bleeds on the Pettersson score, a study was performed using 295 Pettersson scores obtained in 117 patients with severe haemophilia. The patients were born between 1965 and 1994, and had no history of inhibitors. The number of joint bleeds was determined annually from the entry in the clinic and onwards. The localization of bleeds was not assessed. The patients entered the clinic at a median age of 3.6 years, and received intermediate dose prophylaxis, starting at a median age of 5.3 years. Evaluation of 1643 treatment years showed a mean of 6.8 joint bleeds/year. Pettersson scores were obtained at a mean age of 15.9 years (range 1.7-32.9) and had a median value of 4 points (range 0-50). RESULTS AND CONCLUSION: The Pettersson scores began to rise after the age of 5 years and increased with one point for every 13 joint bleeds (95% confidence interval 11-15). No evidence was found of 'autonomous' progression of Pettersson scores, independent of bleeds.

Adolescent↗

PubMed2001

Comparison of coronary-artery bypass surgery and stenting for the treatment of multivessel disease.

BACKGROUND: The recent recognition that coronary-artery stenting has improved the short- and long-term outcomes of patients treated with angioplasty has made it necessary to reevaluate the relative benefits of bypass surgery and percutaneous interventions in patients with multivessel disease. METHODS: A total of 1205 patients were randomly assigned to undergo stent implantation or bypass surgery when a cardiac surgeon and an interventional cardiologist agreed that the same extent of revascularization could be achieved by either technique. The primary clinical end point was freedom from major adverse cardiac and cerebrovascular events at one year. The costs of hospital resources used were also determined. RESULTS: At one year, there was no significant difference between the two groups in terms of the rates of death, stroke, or myocardial infarction. Among patients who survived without a stroke or a myocardial infarction, 16.8 percent of those in the stenting group underwent a second revascularization, as compared with 3.5 percent of those in the surgery group. The rate of event-free survival at one year was 73.8 percent among the patients who received stents and 87.8 percent among those who underwent bypass surgery (P<0.001 by the log-rank test). The costs for the initial procedure were $4,212 less for patients assigned to stenting than for those assigned to bypass surgery, but this difference was reduced during follow-up because of the increased need for repeated revascularization; after one year, the net difference in favor of stenting was estimated to be $2,973 per patient. CONCLUSION: As measured one year after the procedure, coronary stenting for multivessel disease is less expensive than bypass surgery and offers the same degree of protection against death, stroke, and myocardial infarction. However, stenting is associated with a greater need for repeated revascularization.

Adult↗

PubMed2001

Cost-effectiveness of HMG coenzyme reductase inhibitors; whom to treat?

AIMS: Treatment guidelines have been developed for both "primary" and "secondary" prevention of coronary heart disease. These should consider both the efficacy as well as the costs of such treatment, particularly the costs of treatment with HMG co-enzyme A reductase inhibitors (statins). In the context of guideline development in The Netherlands, the cost effectiveness of treatment with statins was analysed. METHODS: Following a modelling approach, cost effectiveness was analysed as a function of a patient's initial risk for new coronary heart disease events, combining results from 4S, CARE, LIPID, WOSCOPS and AFCAPS with Dutch cost data. For each sex and age group, an estimate was made of the level of cardiovascular risks that might correspond to a cost-effectiveness ratio under NLG 40 000 (Euro 18 151) per life year gained. RESULTS: If the 10-year risk of myocardial infarction, stroke or cardiovascular death was estimated at 9% (AFCAPS/TexCAPS), 20% (WOSCOPS), 36% (CARE) 36% (LIPID) and 47% (4S), cost effectiveness was estimated at Euro 51 400, Euro 26 013, Euro 9970, Euro 8028 and Euro 6695. The arbitrary threshold of NLG 40 000 (approximately Euro 18 000) was achieved at a 10 year coronary heart disease event risk ranging from 19% to 26% for different age groups. Assuming the effectiveness of statin treatment decreased with age, a 10-year risk, corresponding to Euro 18 000, varied from 11% (under age 30) to 41% (over age 80). Patients at higher risk levels should be considered for statin therapy. CONCLUSIONS: Treatment costs for primary or secondary prevention are determined predominantly by the costs of statin drugs. The developed model allows comparison of cost effectiveness of statin therapy across a wide range of subjects with or without coronary heart disease. The consensus committee in the Netherlands postulated that drug therapy should be considered in subjects with or without coronary heart disease in which cost-effectiveness is similar. Such groups can be identified using the presented model. When cost effectiveness ratios up to Euro 18 000 per life year gained are deemed acceptable, statin treatment should be considered in most patients with known cardiovascular disease (secondary prevention), and in a limited group of subjects who are at high risk of developing coronary heart disease (primary prevention).

Analysis of Variance↗

PubMed2001

Cost-efficacy in interventional cardiology; results from the EPISTENT study. Evaluation of Platelet IIb/IIIa Inhibitor For Stenting Trial.

AIMS: The EPISTENT study has demonstrated that the combined use of abciximab and stenting as an adjunct to PTCA leads to increased event-free survival compared to either using abciximab or stenting alone. However, this combined strategy may be costly and the additional costs have to be weighted against the additional effects. METHOD AND RESULTS: The 6-months efficacy data from the EPISTENT study are combined with Dutch estimates of unit costs. Adding a stent to a procedure with abciximab further decreases the number of revascularizations at an extra cost of Euros 12,000 (95% upper limit (u.l.) Euros 31,000) per additional major adverse cardiac event-free survivor. Adding abciximab to a stenting procedure decreases the incidence of myocardial infarctions at an extra cost of Euros 13,000 (95% u.l. Euros 27,000) per additional myocardial infarction-free survivor. In the subgroup of diabetics, adding abciximab improves revascularization rates as well, resulting in a cost-efficacy rate of Euros 2000 (95% u.l. Euros 25,000) per additional MACE-free survivor, with uncertainty regions indicating potential costs savings. CONCLUSION: The combination of stenting and abciximab costs about Euros 13,000 to avoid one event after PTCA. In diabetic patients the strategy may be cost-saving.

Abciximab↗

PubMed2001

Cost-effectiveness of oral anticoagulants versus aspirin in patients after infrainguinal bypass grafting surgery.

PURPOSE: Several antithrombotic therapies are available for the treatment of patients with peripheral vascular diseases. It is unknown how quality of life and costs of treatment are influenced by different therapies. This study assessed the cost-effectiveness of oral anticoagulants versus aspirin in patients after infrainguinal bypass grafting surgery. METHODS: Clinical outcome events and event-free survival were collected from 2650 patients in 77 centers who participated in the Dutch Bypass Oral anticoagulants or Aspirin trial. Approximately half the patients had critical ischemia; 60% received vein grafts, and 20% had femorocrural bypass grafts. A model that was primarily driven by clinical outcome events was used as a means of determining quality of life (EuroQol EQ-5D) and costs for each patient. The main outcome measure was the incremental health care costs in relation to the additional number of quality-adjusted life years and the additional number of event-free years. RESULTS: The mean costs during the 21 months of follow-up were epsilon 6875 per patient in the oral anticoagulants group versus epsilon 7072 in the aspirin group (difference, 197; 95% CI, -746 to 343). The event-free survival was 1.10 years in the group treated with oral anticoagulants versus 1.09 years in the group treated with aspirin (difference, 0.01; 95% CI, -0.07 to 0.08), whereas the corresponding quality-adjusted life years were 1.06 and 1.05, respectively (difference, 0.01; 95% CI, -0.03 to 0.06). CONCLUSION: Health care costs, event-free survival, and quality-adjusted life years in patients after infrainguinal bypass surgery were not different in patients treated with aspirin and patients treated with oral anticoagulants. The extra costs of monitoring patients treated with oral anticoagulants were limited and play no role in the decision for treatment.

Aged↗

PubMed2001

Costs in the last year of life in The Netherlands.

The costs of health care in the last year of life are a subject of debate and myth. Expensive interventions at the end of life often are blamed for the rapid increase in health care spending, but evidence about the existence of such exceptionally high expenditures at the end of life is rare and faulty. This investigation examines the development and composition of health care costs at the end of life for all age groups in The Netherlands. In contrast with earlier studies, this research analyzes both acute care (cure) and long-term care (care) costs. As an alternative for the frequently used concept of calendar years, we employed the concept of life years for calculating the costs at the end of life. We found that when life approaches its end, health care expenditures indeed rise sharply, especially in the last months. However, when we compared total cure costs in the last year of life to the total cure costs for the entire population, we concluded that the end-of-life share was only about 10%. Results of this study show that interventions to reduce costs in the last year of life will have only a modest impact compared to the total health care budget.

Acute Disease↗

PubMed2000

Diabetes nephropathy in the Netherlands: a cost effectiveness analysis of national clinical guidelines.

BACKGROUND: In the Netherlands a program on quality assurance in medical care has started in 1996. Clinical professionals, patient organizations and health services researchers formulate evidence based guidelines with a concomitant cost-effectiveness analysis. OBJECTIVES: To examine the cost-effectiveness of guideline recommendations for prevention of nephropathy in diabetes mellitus type 1 and 2. RESEARCH DESIGN: A semi-Markov compartment model was developed. Data from international publications on epidemiological surveys and randomized trials, together with national data on health care use and costs, were used to feed the model. A cohort of diabetes patients without renal disease enters the model. MEASURES: Complication (end-stage renal disease) free years, QALY's, and life-time medical costs per patient treated according to guideline recommendations or current anti-diabetic strategy. RESULTS: Guideline treatment for type 1 diabetes yields 4.2 complication free life years, at a cost-effectiveness ratio of 13 500 (Dutch guilders) NLG per QALY. Type 2 diabetes patients gain 0.2 complication free life years at a cost-effectiveness ratio of 31 000 NLG per QALY. CONCLUSION: Guideline development for diabetes nephropathy, with concomitant cost-effectiveness calculations, has resulted in a transparent guideline with explicit information on long-term cost and effects. The project has brought health care providers and health services researchers together.

Adolescent↗

PubMed1999

The ARTS study (Arterial Revascularization Therapies Study).

The rising costs of health care have forced policy makers to make choices, and new treatments are increasingly assessed in terms of the balance between additional costs and additional effects. The recent recognition that stenting has a major and long-lasting effect enhancing balloon PTCA procedure has made it imperative to compare in patients with multivessel disease the standard surgical procedure with multiple stenting in a large scale multinational and multicentre approach (19 countries, 68 sites). Selection and inclusion of patients is based on a consensus of the cardiac surgeon and interventional cardiologist on equal 'treatability' of patients by both techniques with analysis of clinical follow-up (event-free survival) on the short (30 day), medium (1 year), and long-term (3 and 5 year) with analysis of cost-effectiveness and quality of life (EuroQol and SF-36). Of the entire trial, the primary null hypothesis which needs to be rejected is that there will be no difference in event-free survival or effectiveness (E), at 1 year and also that the direct and indirect costs (C) per event-free year are not different between surgery or stenting. For this to become significant with a power of 90% one needs 1200 patients. Between April 97 and June 98, 1205 patients have been randomized with a monthly recruitment of 83 patients. Expected costs, effects and cost-effectiveness ratio (CE ratio) are: Stent high costs 2 VDStent high costs 3 VDStent low costs 2 VDStent low costs 3 VDCABG costs (C)$19.297$24.566$16.638$20.456$21.350 effects (E)81%81%81%81%88% CE ratio$23.876$30.397$20.586$25.322$24.348 Clinically, stenting is not expected to be more effective than CABG, but should be cost effective in both the 2- and 3-VD group when using the lower cost estimate and in the 2 VD group when using the higher cost assumptions.

Angioplasty, Balloon, Coronary↗

PubMed1999

Incremental cost of medical care after hip fracture and first vertebral fracture: the Rotterdam study.

The aim of this study was to estimate the additional cost of medical care (the incremental cost) caused by incident hip and vertebral fractures, using a matched case cohort design within a longitudinal follow-up study. Incident hip fractures were recorded using the regular follow-up system of the Rotterdam Study. Incident vertebral fractures were recorded by morphometric comparison of spinal radiographs taken at intervals of 2.2 years on average. The matched control group was randomly selected from other participants of the Rotterdam Study in whom no fracture occurred during follow-up, but who were otherwise comparable at baseline. Cases were matched for age, gender, self-perceived health, ability to perform activities of daily life, living situation and general practitioner. Medical expenditure was assessed by retrieval of the general practice medical records and by recording all hospital and nursing home admissions, and all general practice and outpatient visits. Pharmaceutical consumption was recorded through the computerized records of the central pharmacy. Valid results were obtained for 44 pairs (91%) in the hip fracture and for 42 pairs (93%) in the vertebral fracture group. Cost of medical consumption in the year before the hip fracture was similar in patients and control subjects, but the incremental cost in the first year after the hip fracture was almost US$10 000. In the second year after hip fracture the incremental cost was still about $1000. Accounting for the excess mortality in hip fracture patients had little effect on cost in the first year, but cost in the second year was doubled to almost $2000. For vertebral fractures, we did not detect important acute care costs, but these fractures were associated with a yearly recurrent incremental cost of over $1000. However, almost half this difference was already present before the occurrence of the fracture, and was attributable to hospital admissions. The remainder of the incremental cost was mainly due to pharmaceutical consumption and to a lesser extent to admissions to orthopedic surgery wards. We conclude that hip fractures cause excess mortality and an important incremental cost especially during the first year, and that these could probably be avoided by prevention of hip fractures. For vertebral fractures we found no evidence of important acute care costs but we observed a yearly returning incremental cost. Part of this incremental cost, however, was pre-existing and might therefore by caused by co-morbidity.

Aged↗

PubMed1999

Estimating parametric relationships between health description and health valuation with an application to the EuroQol EQ-5D.

Generic health status measures classify patients into different health states. For example, the EQ-5D descriptive system developed by the EuroQol Group classifies patients into 243 health states. Empirical values for the health states are available for only a selection (mostly 12 to 45) of these health states. Several parametric relationships between the descriptive system and the known values can be formulated to estimate the values for the unrecorded health states. This paper describes several of these modeling exercises in a comprehensible way, using the EQ-5D as an illustration. It is shown that the estimation task does not depend on the meaning of the values, but does depend on the selection of the empirically valued health states and the assumptions about the relationship between these values and the descriptive system.

Europe↗

PubMed1999

An economic evaluation of Tomudex (raltitrexed) and 5-fluorouracil plus leucovorin in advanced colorectal cancer.

Our objective was to establish the balance between costs and effects of treatment with Tomudex (raltitrexed) as an alternative to treatment with 5-fluorouracil (5-FU) plus leucovorin (LV) in patients with advanced colorectal cancer. Data were used from an international, open label randomized clinical trial. Costs were calculated by multiplying resource utilization data with Dutch estimates of unit costs. Effects have been expressed in terms of 6 months and 1 year survival, and in terms of the number of patients without severe adverse events including WHO grade 3 and 4 leucopenia, mucositis, anemia and severe asthenia. Cost effectiveness is expressed in terms of costs per additional day of survival and costs per additional patient without any severe adverse event. The clinical results did not show significant survival differences implying great uncertainty about the cost-effectiveness of raltitrexed in terms of additional costs per additional life-year gained. However, 80% of the initially higher cost of raltitrexed ($3132 per patient) is compensated by savings due to a more convenient administration scheme leading to a net cost of $626 per patient treated. Weighed against the decrease in adverse events, a cost-effectiveness ratio results of $3936 per additional patient free of any severe adverse event. More favorable estimates result when the convenience of the administration scheme is valued in positive monetary terms.

Antineoplastic Agents↗

PubMed1999

Impact of goal-oriented and model-based clinical pharmacokinetic dosing of aminoglycosides on clinical outcome: a cost-effectiveness analysis.

The benefits of a pharmacy-based, active therapeutic drug monitoring (TDM) service (ATM) on outcomes were examined in a prospective study at four hospitals. ATM involved pharmacokinetic dosage optimization at the start of treatment, subsequent Bayesian adaptive control, and frequent patient evaluation. Cost-effectiveness was calculated based on real costs. The ATM group comprised 105 patients and 127 patients with nonguided TDM who were followed up as controls. Forty-eight of the ATM and 62 of the nonguided TDM patients had an infection on admission. Peak concentrations in ATM patients were significantly higher (10.6+/-2.9 mg/L; nonguided TDM, 7.6+/-2.2 mg/L; p < 0.01). Trough levels in the ATM group were significantly lower (p < 0.01). There was a trend toward lower mortality in the ATM group (nine of 105 versus 18 of 127; p = 0.26) that was significant for patients with an infection on admission (one of the 48 ATM patients died versus nine of the 62 nonguided TDM patients; p = 0.023). ATM reduced the length of hospital stay for all patients in the study (20.0+/-1.4 days; nonguided TDM, 26.3+/-2.9 days; p = 0.045) and for patients admitted with an infection (12.6+/-0.8 days; nonguided TDM, 18.0+/-1.4; p < 0.001). The incidence of nephrotoxicity was reduced from 13.4% (nonguided TDM) to 2.9% (p < 0.01). With ATM, total costs were lower for all patients (Dutch guilders [DFL], 13,125+/-9,267; nonguided TDM, DFL 16,862+/-17,721; p < 0.05) and for patients admitted with an infection (DFL 8,883+/-3,778; nonguided TDM, DFL 11,743+/-7,437; p < 0.01). Goal-oriented, model-based dosing of aminoglycosides resulted in higher antibiotic efficacy, shorter hospitalization, and reduced incidence of nephrotoxicity. By combining efficacy with savings, ATM offered a significant alternative to usual care.

Aged↗

PubMed1998

[Guidelines and costs].

There is a growing interest in developing clinical guidelines which support the efficiency of medical care by weighting the potential benefits against the costs of interventions. In the recently developed Dutch guideline on reduction of serum cholesterol concentration a formal cost-effectiveness analysis is included. Based on epidemiological arguments a cost-effectiveness ratio of 40,000 Dutch guilders per life year gained was found. In comparison with other preventive health care programmes this amount was considered acceptable. In the past physicians have often taken costs into account in an implicit way when making clinical decisions. The results of the cost-effectiveness analysis vary particularly with the costs of the used statins. In the past physicians have often taken costs into account in an implicit way when making clinical decisions. However, in view of the increase in health care expenditures, it has become the responsibility of physicians to take costs into account more explicitly. Clinical guidelines with a cost-effectiveness analysis can be useful in helping physicians to provide efficient medical care.

Cost-Benefit Analysis↗

PubMed1998

[Economic evaluation of cardiology; background and application].

Effectiveness research is increasingly attracting the attention not only of policy makers but also of the medical profession. Economic evaluation may provide structured information about the cost-effect balance of an intervention as compared with that of a different intervention. Costs can be subdivided into direct and indirect medical costs and direct and indirect non-medical costs. Effects are preferably expressed in life years gained (corrected for quality). A cost-effectiveness ratio indicates the additional costs per additional life year gained (corrected for quality). Economic evaluation can be performed using local, national or international research data. It may use studies that have been completed or in which the economic evaluation is included. A (planned) subgroup analysis may help to define a group of patients for whom the cost-effectiveness ratio is most favourable. The duration of a randomized clinical trial is usually relatively brief; with the aid of a mathematical model it is possible to collect the available information and to calculate extrapolations for longer periods.

Cardiology↗

PubMed1998

Sample size calculation in economic evaluations.

A simulation method is presented for sample size calculation in economic evaluations. As input the method requires: the expected difference and variance of costs and effects, their correlation, the significance level (alpha) and the power of the testing method and the maximum acceptable ratio of incremental effectiveness to incremental costs. The method is illustrated with data from two trials. The first compares primary coronary angioplasty with streptokinase in the treatment of acute myocardial infarction, in the second trial, lansoprazole is compared with omeprazole in the treatment of reflux oesophagitis. These case studies show how the various parameters influence the sample size. Given the large number of parameters that have to be specified in advance, the lack of knowledge about costs and their standard deviation, and the difficulty of specifying the maximum acceptable ratio of incremental effectiveness to incremental costs, the conclusion of the study is that from a technical point of view it is possible to perform a sample size calculation for an economic evaluation, but one should wonder how useful it is.

2-Pyridinylmethylsulfinylbenzimidazoles↗