Step By Step Guide To Economic Evaluation In Cancer Trials

Step by step guide to economicevaluation in cancer trialsWhat is CREST?The Centre for HealthEconomics Research andEvaluation (CHERE) at UTShas been contracted byCancer Australia toestablish a dedicatedCancer ResearchEconomics Support Team(CREST) to provide highquality, expert advice andsupport to Multi-siteCollaborative CancerClinical Trials Groups.FactsheetsCREST will produce aseries of factsheets asresources for cancercollaborative groupresearchers wishing toinclude economicevaluation in their clinicaltrials.Authors: Alison Pearceand Rosalie VineyPrepared: August 2011SUMMARYThis factsheet provides a guide to the steps in aneconomic evaluation in cancer trials. These include:1. Define the alternatives to be assessed in the trial2. Consider the perspective and timeframe. Thisincludes the timeframes for:a. Trialb. Follow upc. Beyond the trial3. Identify, measure and value the resource useassociated with each alternative4. Identify, measure and value the consequences ofeach alternative5. Combine the costs and consequences to producean Incremental Cost-Effectiveness Ratio (ICER)6. Assess the robustness of the results through asensitivity analysis7. Interpret the resultsAn example of a cost utility analysis of radiotherapy innon-small cell lung cancer will be used to illustrateeach of these steps.For more information about CREST, or for other factsheets in thisseries, please see our website:www.chere.uts.edu.au/crest

Step by step guide to economicevaluation in cancer trialsWhat are the steps in an economic evaluationin the context of cancer research?Economic evaluation is “thethe comparativeanalysis of alternative courses of action interms of both their costs and consequences”consequences(Drummond 2005, p9). Figure 1 below showsshothe typical representation of an economicevaluation.This example article describes a ‘societal costcostutility analysis of a Dutch multicenterrandomised trial. that compared the efficacyof radiotherapy schedules.in 297 patientswith inoperable non-smallsmall-cell lung cancer’.Step 1: Define alternativesFigure 1: Economic evaluation frameworkThere are seven main steps which are typicalto economic evaluations, including thoseconducted within or alongside cancer clinicaltrials. Each of these will be described in thisfactsheet.An example from the literature has beenselected to demonstrate each of these stepsin practice. The reference for this paper is:van den Hout WB, Kramer GWPM,Noordijk EM, and Leer JWH. 2006. Costutility analysis of short- versus long-courselongpalliative radiotherapy in patients withnon-small-cell lung cancer. Journal of theNational Cancer Institute, 98(24):1786-94.98(24):1786This article is available for download from theCREST website est)or is freely available online.Economic evaluation is always concerned withcomparing alternatives. It may be that one ofthe alternatives is a ‘do nothing’ or ‘standardpractice’ arm, however the costs andoutcomes of such alternatives must still bedefined, measured and valued.In defining the alternatives,alternatives you must considerwhat kind of economic evaluation will bemost appropriate. This decision should bebased on the nature of the research question,and the anticipatedicipated differences between thecosts and consequences of your alternatives.The three types of economic evaluation toconsider are cost effectiveness analysis, costutility analysis and cost benefit analysis.In a cost effectiveness analysis (CEA), thebenefits of the interventions are measured in“natural” units. For example, such measuresinclude cases detected, or life yearsyear saved. Ina CEA, the research question is directed atassessing how to maximise the achievementof a particular health outcome using availablehealth resources. Thus, the results of a CEAare reported as (for example) cost per casedetected or cost per life year gained.

Step by step guide to economicevaluation in cancer trialsIn a cost utility analysis (CUA), effectiveness ismeasured in preference based units. Thismeans that the natural units (eg lives saved orlife years gained) are combined with ameasure of the value that individuals place onthat outcome. The most common example ofa preference-based measure is the QualityAdjusted Life Year (QALY). In a CUA theresearch question is directed at assessing howto maximise health gain from availableresources. The results of a CUA are reportedas cost per QALY gained.Finally, in a cost benefit analysis (CBA), theeffectiveness of an intervention is measuredterms of its monetary value (ie in dollars).This allows the net benefit (ie the cost ofintervention minus the value of the benefit)to be calculated. In a CBA, the researchquestion is directed at assessing how tomaximise social welfare. Whilst this has somelogical appeal, the valuation of health careoutcomes in dollar terms is difficult, and CBAis not often used in health research.ExampleThe alternatives to be considered in theexample paper are long course versus shortcourse radiotherapy. The background sectionto the paper describes the differences that theauthors anticipate observing between longand short course treatment in terms ofsurvival gains (evidence was inconclusive priorto their study which found long course moreeffective) and costs (higher medical, patientand ongoing costs with long coursetreatment). The type of study selected was acost-utility analysis, as they used QALYs as an‘overall measure of the patients’ quantity andquality of life’, and compared this to the totalcosts to society.Step 2: Define perspective, timeframe andpopulationThe time period for an economic evaluationshould be considered in the context of thecosts and consequences of the interventionsunder investigation. A clinical trial is usuallydesigned to follow patients up until a specificoutcome of interest or endpoint has beenreached. While in some cases this may besufficient time for the relevant costsassociated with the intervention and its longterm outcomes to be observed, in some casesadditional follow up beyond the end of thetrial may be required.An alternative to extended follow up, whichcan be time consuming and expensive, is theuse of modelling. This approach involves theuse of trial data plus additional informationabout the longer term effects (usually sourcedfrom the literature) and local informationabout the ongoing and/or long term costs tobe used to model the costs and effectsbeyond the study follow up period.The perspective of a study is primarily relatedto the intended audience for the results. Inselecting a perspective, you are in effectselecting the range of costs and consequencesto be included in the economic evaluation. Asocietal perspective will include all costs andconsequences which are borne by societyrelated to that intervention. This is the goldstandard for economic evaluations, but can becomplex to implement. In Australia, thePharmaceutical Benefits Advisory Committee

Step by step guide to economicevaluation in cancer trials(PBAC) define a societal perspective to includea broad definition of health care resources,including those paid for by patients,governments, health insurance agencies andany other part of society are included.However indirect costs such as productivitylosses for patients and carers are usually notincluded. While this is not a true societalperspective, it is one which is more practicalthan considering all potential costs. Morecommonly, a hospital or health serviceperspective is taken, as this is often the mostrelevant to the decision makers who will beutilising the results of the economicevaluation.Similarly, defining a target population is alsoimportant for perspective, because factorssuch as age, comorbidities, risk factors,location and socioeconomics can influenceboth the resource use and consequences ofinterventions.ExampleThe example paper followed patients for oneyear after randomisation. Given the relativelyshort survival time of patients receivingpalliative care for non-small-cell lung cancer,this would appear to be an appropriatetimeframe for both costs and consequences.The perspective taken in the example paper isan example of the societal perspective asdefined by PBAC, including “medical costs ofradiotherapy as well as other health care costsand costs incurred by the patients during theirremaining lifetime”.Step 3: Identify, measure and value resourceuseFirst, the resources required for each arm ofthe trial need to be identified. Things toconsider include who is required to do whatto patients, when each activity occurs andhow often, and how these activities may bedifferent to standard clinical practice.The next consideration is what reliablesources of information can be accessed tomeasure the resource use. Options includecollecting data directly from patients orproviders during the trial (patient diaries forexample), identifying similar work donepreviously which can be adapted to yourstudy (through a literature review), or usingadministrative data applied to your sample(for example, local admission rates forchemotherapy).Finally, the value of each resource used needsto be determined. In this step, dollar valuesare obtained for all resources. Again, somecosts may be able to be collected directlyduring the trial (eg patient out-of-pocketcosts), but it is also common to useadministrative data or tariffs to determineappropriate dollar values. Examples of thisinclude using MBS item numbers andassociated values to determine the cost ofdiagnostic, medical or procedural costs, or thePBS to determine prescription drug costs.ExampleThe resources identified for inclusion in theexample paper were medical costs ofradiotherapy, non-medical costs ofradiotherapy, such as time and travel costs for