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STUDYPROTOCOLOpenAccessAbrieftooltoassesscapacitytoconsentformedicalcareamonghomelessindividualswithproblematicsubstanceuse:studyprotocolDarleneTaylor1*,LouiseMasse2,AnitaHo3,MichaelLRekart4,MarkTyndall5,BonnieHenry1,JoanneClifton6,LaurennaPeters1,GinaOgilvie1andJaneBuxton1AbstractBackground:Publichealthcareincreasinglyusesoutreachmodelstoengageindividualswhoaremarginalized,manyofwhommisusesubstances.
Problematicsubstanceuse,togetherwithmarginalizationfromthehealthcaresystem,amonghomelessadultsmakesitdifficulttoassesstheircapacitytoconsenttomedicalcare.
Toolshavebeendevelopedtoassesscapacitytoconsent;however,thesetoolsarelengthyandunsuitableforoutreachsettings.
Theprimaryobjectiveofthisstudyistodevelop,validate,andpilotabriefbutsensitivescreeninginstrumentwhichcanbeusedtoguidecliniciansinassessingcapacitytoconsentinoutreachsettings.
Thegoalofthispaperistooutlinetheprotocolforthedevelopmentofsuchatool.
Methods/Design:AbriefassessmenttoolwillbedevelopedandcomparedtotheMacArthurCompetencyAssessmentToolforTreatment(MacCAT-T).
Aslistof36possiblequestionswillbecreatedbyusingqualitativedatafromclinicianinterviews,aswellasconceptsfromtheliterature.
Thislistwillberatedbycontentexpertsaccordingtotheextentthatitcorrespondstothetestobjectives.
Theinstrumentwillbevalidatedwith300homelessadultvolunteerswhoself-reportproblematicsubstanceuse.
ParticipantswillbeassessedforcapacityusingtheMacCAT-Tandthenewinstrument.
AcombinationofClassicalTestTheoryandadvancedpsychometricmethodswillbeusedforthepsychometricanalysis.
CorrectedItem-Totalcorrelationwillbeexaminedtoidentifyitemsthatdiscriminatepoorly.
GuidedexploratoryfactoranalysiswillbeconductedonthefinalselectionofitemstoconfirmtheassumptionsforaunidimensionalpolytomousRaschmodel.
Ifunidimensionalityisconfirmed,anunstandardizedCronbachAlphawillbecalculated.
Ifmulti-dimensionalityisdetected,amultidimensionalRaschanalysiswillbeconducted.
ResultsfromthenewinstrumentwillbecomparedtothetotalscorefromtheMacCAT-TbyusingPearson'scorrelationtest.
Thenewinstrumentwillthenbepilotedinreal-timebystreetoutreachclinicianstodeterminetheacceptabilityandusefulnessofthenewinstrument.
Discussion:Thisresearchwillbuildontheexistingknowledgeaboutassessingcapacitytoconsentandwillcontributenewknowledgeaboutassessingindividualswhosejudgmentisimpairedbysubstanceuse.
Keywords:Capacitytoconsent,Substanceuse,Psychometricinstruments,Vulnerablepopulations*Correspondence:darlene.
taylor@bccdc.
ca1BCCentreforDiseaseControl,UniversityofBritishColumbia,655West12thAvenue,Vancouver,BCV5Z4R4,CanadaFulllistofauthorinformationisavailableattheendofthearticleARCHIVESOFPUBLICHEALTH2013Tayloretal.
;licenseeBioMedCentralLtd.
ThisisanOpenAccessarticledistributedunderthetermsoftheCreativeCommonsAttributionLicense(http://creativecommons.
org/licenses/by/2.
0),whichpermitsunrestricteduse,distribution,andreproductioninanymedium,providedtheoriginalworkisproperlycited.
Tayloretal.
ArchivesofPublicHealth2013,71:11http://www.
archpublichealth.
com/content/71/1/11BackgroundSubstancemisuseisassociatedwithahighprevalenceofphysicalandmentalco-morbiditiesrequiringmedicalcare.
In2009therewereanestimated4,049hospitaliza-tionsasaresultofillicitdruguseinBritishColumbia(BC)Canada[1].
Thesedatahighlighttheimportanceofprovidingpreventionandtreatmentservicestomar-ginalizedgroupswithaddictionswhoareparticularlyvulnerabletointimidation,manipulation,coercionorex-ploitation[2].
Thispopulationoftenreceivescareinstreetoutreachsettingswhereclinician-clientencountersarebrief,creatingcomplexchallengestoclinicianswhoattempttoobtainconsentfortreatmenttoclientswhosedecision-makingcapacitymaybeimpaired[3].
Informedconsentfortreatmentisdefinedasan"indi-vidual'sautonomousandvoluntaryauthorizationofamedicaldecision"forwhichanindividualhassubstan-tialunderstandingoftherisksandbenefits[2].
TheBCHealthCare(Consent)andCareFacility(Admission)Act[4]clearlystipulatesthatindividualsmustbecapableofmakingrationaldecisionsabouttheirhealthandde-finescapacityastheabilitytounderstandthemedicalcarebeingoffered(risks,benefits,andalternatives)andhowitappliestothepersonbeingofferedcare[4].
Thisiscontrastedwithanequallyimportantrighttoinfor-medrefusal.
However,thepracticalmethodsforasses-singcapacitytoconsent(CTC)inpublichealthcaresettingsareunclear.
Unlikethesituationinmostclinicalsettings,consentfromclientsinoutreachsettingscannotalwaysbeimpliedespeciallywhenthehealthprofes-sionalseeksoutclientsratherthanhavingthemseekcare.
Inthesecases,verbalconsentmustbeobtainedanditisimperativethatcliniciansassessCTCbeforede-liveringhealthcare.
AssessingimpairedCTCNumeroustoolshavebeendevelopedtoassessCTCforclinicaltreatmentand/orresearchpurposes.
Arecentsystematicreview[5]providesacomprehensiveassess-mentof23instrumentsforassessingCTC.
Themajorityofinstrumentshavebeendevelopedforandvalidatedinpopulationswithmentalillnesssuchasdepression,schizophrenia,andAlzheimer'sdiseaseandinvolveastructuredorsemi-structuredinterviewusinghypothet-icalvignettesorrealdecision-makingscenariosthatlast15–90minutes.
Thesescalesprimarilyfocusonelementsofunderstanding,recalloffacts,theabilitytoappreciatethefactthatthestudyortreatmentinvolvesthemandtheabilitytostatethereasonfortheirdecision.
Currentscalesvarygreatlyintermsofstandardizationandsco-ringprocedures.
ThemostwidelyusedinstrumentistheMacArthurCompetencyAssessmentTool(MacCAT)(fortreatmentorforresearch)whichhasbeenshowntohavegoodpsychometricpropertiesandtakes15–30minutestoad-minister[6,7].
Whilethesetoolsmaybeusefulwhentheclinicianhasampletimetoadministerandscorethein-strument,itisimpracticalinstreetoutreachsettings,whereclinicalencountersaretypicallybrief.
Notool,toourknowledge,hasbeendevelopedtoas-sessCTCamonghomelessindividualswithproblematicsubstanceuse.
Thisgroupisuniqueinthatsomeindi-vidualsmaybebetterabletogiveconsentwhentheyareundertheinfluenceofasubstancethanwhentheyareexperiencingwithdrawalsymptoms.
ItisrecognizedthathomelessadultswithproblematicsubstanceusehaveadiminishedCTC,makingthemvulnerabletoexploita-tion[8].
OurresearchwilladdresstheparticularlysalientproblemofassessingCTCinthispopulation.
Thepurposeofthisresearchstudyistodevelopabrieftoolthatcanbeusedbypublichealthcareclinicianstoguidetheirassessmentoftheirclients'capacitytopro-videinformedconsentformedicalcarewhenundertheinfluenceofsubstances.
ThisstudyhasbeenapprovedbytheUniversityofBritishColumbiaresearchethicsboard.
ResearchobjectivesTheobjectivesforthisstudyareasfollows:(1)tosurveyclinicianswhoprovideservicestoclientswhomisusesubstancestodeterminetheircurrentpracticesforas-sessingcapacitytoconsentforclinicalcare,(2)toex-ploretheexperiencesofprovidingconsentfromtheperspectiveofpeoplewhomisusesubstances,and(3)todevelopabriefassessmenttoolwithacceptablepsycho-metricpropertiesthatcanbeusedtoassessCTCformedicalcareinoutreachsettings.
Methods/DesignAseriesofqualitativeinterviewswillbeconductedamongapurposivesampleofcliniciansthroughoutBCwhodelivercaretohomelessclientswithproblematicsubstanceuse.
Recruitmentwillbeconductedbyemailadvertisementdistributedbyinfectiouscontrolleadersineachhealthauthority,andsamplingwillbedoneuntiltheoreticalsaturationisreached(estimatedtobe20par-ticipants).
Maximum-variationsamplingwillbeem-ployed,whichallowsexplorationofbothtypicalandunusualconceptsacrossabroadrangeofsettings[9].
Criticalsocialtheoryanddecision-makingtheorywillbeusedtocreateasemi-structuredinterviewguidetoin-terviewparticipantsabouttheircurrentpracticeforassessingCTC,i.
e.
,theconceptualelementstheycon-siderwhenassessingcapacity,themethodstheyusetoassesstheseelements,andthethresholdtheyusetomakeafinaldecisionaboutcapacity.
Interviewswillbeconductedinaprivateofficeattheparticipant'splaceofwork.
Tayloretal.
ArchivesofPublicHealth2013,71:11Page2of4http://www.
archpublichealth.
com/content/71/1/11Aseriesofqualitativeinterviewswillalsobecon-ductedwithaconveniencesampleofadultsthroughoutBCwhoarehomelessandwhoself-reportasabusingsubstances.
Recruitmentwillbeconductedthroughadvertisementatcommunity-basedorganizationsandthroughwordofmouth.
Samplingwillbedoneuntiltheoreticalsaturationisreached(estimatedtobe25par-ticipants).
Thepurposeoftheseinterviewsistoexploretheexperienceofprovidingconsentorobtainingmed-icalcarefromtheperspectiveoftheseindividuals.
Powerinequitieswillalsobeexplored.
Interviewswillbecon-ductedinaprivateroomwherethecommunityorgani-zationmeets.
A$20cashhonorariumwillbeprovidedtoparticipants.
Allinterviewswillbeaudiotapedandtranscribedver-batimwithoutpersonalidentifiers.
Conceptsandthemeswillbeidentifiedinthedata,andaninterpretivedes-criptionanalysis[10],usingbothinductive(allowingconceptsandthemestoemergefromthedata)andde-ductive(usingconceptsandthemesthataredescribedintheliterature)approaches,willbeconductedtodeter-minehowassessmentofCTCcanbetranslatedintoclinicalpractice.
InstrumentdevelopmentAcomprehensivereviewoftheliteraturewillbecon-ductedtoexaminetheexistinginstrumentsforde-terminingCTC.
Inaddition,theoreticalconceptsrelatedtoCTCwillbereviewed.
Theproposedtoolwillbeconstructedusingtheoreticalconcepts,legalconcepts,andknowledgegainedfromqualitativeinterviews.
Reli-able,validatedquestionsfromexistinginstrumentswillbeaddedtothelistofpossiblequestions.
Theproposedquestionswillbeprovidedtoapanelofexpertstoestablishitem-objectivecongruencybyratingeachquestion(item)usingtheOsterlindmethod[11].
Thepanelofexpertswillincludefourdoctorsandfournursesfrompublichealth,onepractitionerwhodeliversclinicalcaretothetargetpopulation,onelawyer,oneethicist,anaddictionsspecialist,andapsychiatrist.
Expertswillbeencouragedtosuggestotherquestionswhichmayhavebeenomitted.
AmodifiedDelphipro-cesswillbeusedtoachievegroupconsensusabouttherelevancyofeachquestion.
Questionswithdiscordantratingswillbefurtherdiscussedinpersonuntilconsen-susisreached.
Onceanear-finalversionoftheinstrumentiscreated,pilottesting[12]willbeconductedwithfiveindividualsfromthetargetpopulation.
Duringthisprocess,partici-pantswillbeaskedtorespondtothequestionsandaskedwhytheychosetheresponsetheychoseandwhatthequestionmeanttothem.
Atthistime,thenumberofresponseoptionswillbeassessedforappropriateness.
InstrumentvalidationThreehundredclientswhoaremorethan18yearsold,andwhospeakandreadEnglish,self-reportasbeinghomeless,andself-reportabuseofsubstanceswillberecruitedforavalidationstudythrougharecruitmentposterplacedinadowntownVancouvercommunity-basedorganization.
Ashortquestionnaireondemogra-phics,substanceuse,andhistoryofmentalillnesswillbeadministered.
Participantswillbepresentedwithasimu-latedconsentforahypotheticalmedicalscenario.
Theywillthenbeassessedbyapsychiatristtocaptureaclin-icalassessmentofcapacity.
Next,participantswillbead-ministeredtheMacCATfortreatment(MacCat-T)toolfollowedbytheadministrationofthenewassessmenttool,conductedbyaresearchnurseblindedtotheclinicalandMacCAT-Tresult.
AsecondresearcherwillobservetheinterviewandscoreitindependentlyandaKappasta-tistic[13]willbecalculatedusingSPSS14todetermineinter-raterreliability.
AKappascoreof>0.
8willbeconsid-eredacceptable[14].
PsychometricanalysisAcombinationofclassicaltesttheoryandadvancedpsy-chometricmethodswillbeusedforthepsychometricanalysis.
Anitemanalysiswillbeconductedbyexamin-ingthecorrecteditem-totalcorrelationtoidentifyitemsthatdiscriminatepoorly[15,16].
Removalofitemswithcorrecteditem-totalcorrelationof<0.
20willbeconsid-eredifthecontentisnotconsideredclinicallyimportant.
Weaimtocreateaninstrumentthathasthefewestitemswhilemaintaininggoodpsychometricproperties.
Theminimumnumberofitemsrequiredtoprovideareliabilityofatleast0.
80willbecalculatedusingtheSpearmanBrownprophecyformula[17].
Guidedexploratoryfactoranalysiswillbeconductedonthefinalselectionofitemstoconfirmtheassump-tionsforaRaschmodel[18].
Ifmulti-dimensionalityisconfirmedmultidimensionalRaschanalysiswillbeconducted.
Ifunidimensionalityisconfirmedanunstan-dardizedCronbachAlphawillbecalculatedandaglobalsummaryscorewillbecreated.
TheglobalscoreandtheMacCAT-TscorewillbecomparedusingaPearson'scorrelationtest.
Acutoffvalueforthenewinstrumentwillbecreatedbyconductingareceiveroperatingchar-acteristicanalysisusingacombinationoftheclinicalas-sessmentofcapacityandthefourdomainscoresfromtheMacCAT-Tasthegoldstandard.
Iftheclinicalas-sessmentandallfourMacCAT-Tdomainscoresindicatecapacity,thenthegoldstandardassessmentwillbere-cordedas"hascapacity".
Ifanyofthesefiveelementsindicatesalackofcapacity,thenthegoldstandardas-sessmentwillberecordedas"doesnothavecapacity".
Resultswillbestratifiedbyalcoholuseonly,druguseonly,andmentalstatus.
Tayloretal.
ArchivesofPublicHealth2013,71:11Page3of4http://www.
archpublichealth.
com/content/71/1/11DiscussionThisstudywilladdressanimportantcomponentofcur-rentpracticeforassessingCTCtotreatmentamongpo-pulationswithaddictionswhomayhaveimpairedCTCandthusbevulnerabletocoercion.
Thenewinstrumentwillprovideguidancetoclinicianswhodelivercaretoindividualswithproblematicsubstanceusewhomayormaynotbeimpairedduringaclinicalencounter,espe-ciallyencountersthatoccurinoutreachsettings.
Notools,toourknowledge,havebeendevelopedtoassessCTCamongthesevulnerableindividuals.
Moreover,exis-tingtoolsarecumbersomeandmayconstructabarriertocare.
Whilethestudywillbeconductedinoutreachset-tings,itislikelythatthistoolwillbetransferabletoothersettingswheremedicalencounterswithindividualsim-pairedbysubstancesarebrief,suchasemergencyrooms,emergencymedicalservices,andcommunityclinics.
AbbreviationsBC:BritishColumbia;CTC:Capacitytoconsent;MacCAT:MacArthurcompetencyassessmenttool;MacCAT-T:MacArthurcompetencyassessmenttoolfortreatment.
CompetinginterestsAllauthorsdeclarethattheyhavenocompetinginterests.
Authors'contributionsDTwasresponsiblefordraftingthearticle.
DT,LM,JC,GO,andJABwereresponsibleforconceptionanddesignofthestudy.
Allauthorswereresponsibleforcriticalrevisionofimportantintellectualcontentandapprovalofthefinalversiontobepublished.
AcknowledgementsThisresearchproposalhasbeenfundedbytheCanadianInstitutesforHealthResearch.
Authordetails1BCCentreforDiseaseControl,UniversityofBritishColumbia,655West12thAvenue,Vancouver,BCV5Z4R4,Canada.
2DepartmentofPediatrics/SchoolofPopulationandPublicHealth,UniversityofBritishColumbia,4480OakStreet,L408,Vancouver,BCV6H3V4,Canada.
3CentreforAppliedEthics,UniversityofBritishColumbia,6356AgriculturalRoad,Vancouver,BCV6T1Z2,Canada.
4SchoolofPopulationandPublicHealth,UniversityofBritishColumbia,2206EastMall,Vancouver,BCV6T1Z3,Canada.
5DepartmentofInfectiousDiseases,UniversityofOttawa,75LaurierAvenueEast,Ottawa,ONK1N6N5,Canada.
6DepartmentofSurgery,UniversityofBritishColumbia,899West12thAvenue,Vancouver,BCV5Z1M9,Canada.
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doi:10.
1186/0778-7367-71-11Citethisarticleas:Tayloretal.
:Abrieftooltoassesscapacitytoconsentformedicalcareamonghomelessindividualswithproblematicsubstanceuse:studyprotocol.
ArchivesofPublicHealth201371:11.
SubmityournextmanuscripttoBioMedCentralandtakefulladvantageof:ConvenientonlinesubmissionThoroughpeerreviewNospaceconstraintsorcolorgurechargesImmediatepublicationonacceptanceInclusioninPubMed,CAS,ScopusandGoogleScholarResearchwhichisfreelyavailableforredistributionSubmityourmanuscriptatwww.
biomedcentral.
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ArchivesofPublicHealth2013,71:11Page4of4http://www.
archpublichealth.
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