Anais
Brasileiros
de
Dermatologia
www.anaisdedermatologia.org.br
INVESTIGATION
Improving
skin
picking
diagnosis
among
Brazilians:
validation
of
the
Skin
Picking
Impact
Scale
and
development
of
a
photographic
instrument
夽,夽夽
Alice
Castro
Menezes
Xavier
a,∗,
Camila
Maria
Barbieri
de
Souza
b,
Luís
Henrique
Fernandes
Flores
b,
Clarissa
Prati
c,
Cecilia
Cassal
d,
Carolina
Blaya
Dreher
e,faPostgraduateprogramofHealthSciences,FederalUniversityofHealthSciencesofPortoAlegre,,PortoAlegre,RS,Brazil bMedicalSchool,FederalUniversityofHealthSciencesofPortoAlegre,PortoAlegre,RS,Brazil
cOutpatientDermatologyClinic,PontificalCatholicUniversityofRioGrandedoSul,PortoAlegre,RS,Brazil dOutpatientClinicofPsychodermatology,OutpatientClinicofHygienicDermatology,RioGrandedoSulStateHealth
Department„PortoAlegre,RS,Brazil
eDepartmentofClinicalMedicine---Psychiatry,MedicalSchool,FederalUniversityofHealthSciencesofPortoAlegre,,Porto
Alegre,RS,Brazil
fDepartmentofPsychiatryandForensicMedicine,MedicalSchool,FederalUniversityofRioGrandedoSul,PortoAlegre,RS,
Brazil
Received29May2018;accepted21October2018 Availableonline30September2019
KEYWORDS Photography; Psychometrics; Symptomassessment; Validationstudies Abstract
Background: Skinpickingdisorderisaprevalentdisorderfrequentlycomorbidwithdepression and anxiety,which is underdiagnosed mainlyby dermatologists.Assessment ofskin picking disorderisbasedoninstrumentsinfluencedbytheawarenessaboutskinpickingdisorderand comorbidsymptoms.Todate,thereisnovalidatedinstrumentforBrazilianindividualsnoran instrumenttoevaluatetheseverityofskinlesionsinanobjectiveway.
Objectives: ValidatetheSkinPickingImpactScaleforBrazilianPortugueseandcreatea pho-tographicmeasurementtoassessskinlesions.
Methods: ThesamplewasassessedthroughtheSkinPickingImpactScaletranslatedinto Brazil-ian Portuguese,theHamiltonAnxietyScale, theBeckDepression Inventory,andtheClinical GlobalImpressionScale.Thepatients’skinlesionswerephotographed.Photoswereevaluated regardingactiveexcoriation,crust/bleeding,exulceration,andlinearlesions.
夽 Howtocitethisarticle:XavierAC,SouzaCM,FloresLH,PratiC,CassalC,DreherCB.ImprovingskinpickingdiagnosisamongBrazilians:
validationoftheSkinPickingImpactScaleanddevelopmentofaphotographicinstrument.AnBrasDermatol.2019;94:553---60.
夽夽StudyconductedattheServic¸odePsiquiatria,UniversidadeFederaldeCiênciasdaSaúdedePortoAlegre;HospitalMaternoInfantil
PresidenteVargas,PortoAlegre,RS,Brazil.
∗Correspondingauthor.
E-mail:[email protected](A.C.Xavier).
https://doi.org/10.1016/j.abd.2018.10.001
0365-0596/©2019PublishedbyElsevierEspa˜na,S.L.U.onbehalfofSociedadeBrasileiradeDermatologia.Thisisanopenaccessarticle undertheCCBYlicense(http://creativecommons.org/licenses/by/4.0/).
Results: Therewere63patientsincluded.TheSkinPickingImpactScaletranslatedintoBrazilian Portuguesehadgoodinternalconsistency(Cronbach’salpha=0.88),whichtestsof goodness-of-fit,showingasuitablemodel.Thereliabilityofphotographicmeasurementwas0.66,withahigh internalconsistency(Cronbach’salpha=0.87).Photographicmeasurementwasnotcorrelated withtheSkinPickingImpactScale,theClinicalGlobalImpressionScale,orcomorbidsymptoms.
Studylimitations: Lackofapreviouslyvalidatedinstrumenttoevaluatedermatillomaniainthe Brazilianpopulationforcomparison.
Conclusion: TheSkinPickingImpactScalevalidatedinBrazilianPortugueseisagoodinstrument toevaluateskinpickingdisorder.Photographicmeasurementisaconsistentwayofassessing skinlesions,butitdoesnotreflecttheimpactofskinpickingdisorderontheindividual’slife. ©2019PublishedbyElsevierEspa˜na,S.L.U.onbehalfofSociedadeBrasileiradeDermatologia. ThisisanopenaccessarticleundertheCCBYlicense(http://creativecommons.org/licenses/ by/4.0/).
Introduction
Skinpickingdisorder(SPD),alsoknownasexcoriation dis-order or dermatillomania, affects up to 5.4% of general population and up to30% of psychiatricpatients.1 It was
included as a formal diagnosis in the Diagnosticand Sta-tistical Manual ofMental Disorders, FifthEdition (DSM5), characterizedbythefollowing:recurrentpickingattheskin resultinginskinlesions;attemptstostoppicking;clinically significant distress, and absenceof another causefor the habit.2SPD severityisrelatedtoimpairmentinqualityof
life, and is correlated with anxiety disorder (up to48%), majordepression(8---28%),andsubstanceabuse(14---36%).3
Although it is a psychiatric disorder, the majority of patientsfirstseekhelpwithadermatologist,and differen-tial diagnosis should be made withdelusional parasitosis, prurigo simplex, subacute Hebra and scabies.4 Among
patientswithSPDwhoseekhelp,only53%receivethe cor-rect diagnosis, made by dermatologists in 2.5% of cases andby psychiatristsin56%.1SPD isachronicdisorderand
thehabitusuallyisautomatic,withonly24%ofindividuals reportingfullawarenesspriortopicking.5Besidesthenails,
patientscanusepinsortweezerstomanipulatetheirskin, and80%havenotabletissuedamage.1
The severity of SPD and the response to treatment havebeenevaluatedwithdifferentinstruments: clinician-reportedmeasures,self-reportedmeasuresofSPDseverity, andself-reportedmeasuresofSPDimpact.TheYale-Brown ObsessiveCompulsive Scale ModifiedforNeurotic Excoria-tion(NE-YBOCS)is areliableclinician-reportedinstrument thatevaluatesthoughtsandbehaviorsrelatedtoskinpicking duringthelastsevendays,butdoesnotspecificallyassess thesocialdistresscausedbythedisease.6Amongthe
self-reportedmeasures,the skinpicking scaleis a moderately reliable instrument that assesses SPD severity during the past week and that has been correlated with depressive symptoms.7,8 The Skin Picking Symptom Assessment Scale
is a less-used,reliable, self-reported instrument to eval-uate SPD severity during the last seven days.6 The Skin
PickingRewardScaleisareliableinstrumenttoassessthe aspectsof‘‘liking’’and‘‘wanting’’theSPDhabit,without definition of the time of symptoms evaluation, substan-tiallyinfluencedbytheself-reflectionregardingthehabit.6
All these measures evaluate the frequency of this habit butnotthedistresscaused.The SkinPickingImpact Scale
(SPIS) is the only scale that evaluates the psychological impact of this disorder; it is a patient-rated scale with highreliability,evaluatingsymptomsduringthelastseven days, with higher scores considered more severe impact. The SPIS hasbeen correlatedwithdepressiveandanxious symptoms.9
The available instrumentstoassess SPD depend of the patient’s awareness about the habit, which is not com-mon. The NE-YBOCSalso depends on clinician knowledge aboutemotional distress,whichisnoteasy for dermatolo-gists,whoaregenerallythe firstprofessionalaccessed by patients suffering from SPD. Self-applied instruments are alsoinfluencedby emotionalaspectsof thepatient: anxi-ety,depression,andsocialavoidance,whichisfrequentin SPD.Inaddition,thebodyareaaffecteddirectly influence thescales,withpatientswhopicktheirfacesgenerally hav-ingahighscorebecauseofhigherself-esteemimpact.10The
majorityofinstrumentsevaluatethehabitduringlastseven days,althoughitisknownthatSPDisachronicdiseaseand thatthetimetohealseverewoundswouldbelonger.Even thoughtherearedifferentmethodsofevaluationforSPD,no studyhasevaluatedskin-pickingseveritythroughdifferent approachesatthesametime.
ThereisalackofanobjectivewaytoassessSPD symp-tomsnotinfluencedbypatients’awarenessofthehabitor otheremotionalconditions.Apotentialadvantageofa pho-tographicevaluationisthereductionofreportingbiasand recognitionoftheseverityoftheskinlesions.Totheauthors’ knowledge,nophotographicmeasurehasbeenvalidatedto assessSPDseverity,withonlytwostudieshavingused pho-tographstoevaluateSPD,without validityor reliabilityof themeasurebeingpublished.11,12
Despite the high prevalence of SPD, to the authors’ knowledge no instruments to assess this pathology have been validated to beused in theBrazilian population. As the impact of SPD on a patient’s life is important infor-mation about the individual’s suffering, and because the SPIS, a highly reliable scale, was previously translatedto BrazilianPortuguese(FerrãoY.A.andBedin,N.R.,datanot published), the validationof thisinstrument for Brazilian populationcouldbeavaluablewaytoassessSPD.
TheaimofthisstudyistovalidatetheSPISforthe Brazil-ianpopulationandtocreateaphotographicinstrument(PI) to assess SPD severity, applicable by dermatologists.This study works withthe hypothesis that the SPIS and the PI
canbereliableandeasilyusedinclinicalpractice,withPI reflectingmoredirectlytheseverityofSPD,independently ofcomorbidsymptoms.Inthisway,thediagnosticratesof SPDcanbeincreased.
Methods
Studydesignandparticipants
Thiswasacross-sectionalstudyinwhichparticipantswere enrolledthroughpublicadvertising inthe periodbetween July 2014andJanuary2018. Theinclusion criterionwasa diagnosisofSPD accordingtoadiagnosticinterview struc-tured by theDSM 5.2 The exclusion criteriawere current
psychoticdisorder,moderateorsevereintellectual disabil-ity(twoindividualsexcluded),orsuiciderisk(oneindividual excluded) asassessed by clinical interview conducted by trained psychiatry residents. Individuals who met exclu-sion criteria receivedreferrals to appropriate community resources.
The primaryendpoint of the studywastovalidate the SPISfortheBrazilian populationandtocreateavalidand reliableobjectivePItoassessSPDseverity.Secondary out-comeswerethecorrelationbetweenPIandtheinstruments thatassessthecomorbiditiesandimpactonlifeofSPD,such astheBeckDepressionInventory(BDI),theHamilton Anxi-etyScale(HAM-A),andtheClinicalGlobalImpressionScale (CGI).13---17
Procedureandmeasures
Psychiatricdiagnosticinterviewswereconductedbya psy-chiatryresident and discussed withasenior researcher. A check-list of SPD symptoms according to the DSM 5 was applied2andtheMiniInternationalNeuropsychiatric
Inter-view(MINI)translatedtoBrazilian Portuguesewasusedto assesspsychiatriccomorbidities.2,18,19Aftertheinclusionin
thestudy,the baselineassessment wasconductedby two trainedevaluatorswithahighinter-raterreliability(kappa coefficient=0.9),applyingtheBDI,theHAM-A,theCGI,and the SPIS translated to Portuguese.9,14,15,17 The evaluators
also took photos of patient’s regions with active lesions, usinganiPhone7camerawith12megapixels,withoutzoom, atadistancefromcameratoskinof7to11inches,ata90◦ angle.
ThePortugueseversionofthe21-itemBDI,validatedfor Braziliansubjects,wasusedtoassessdepressivesymptoms duringthelastweek,withscorevaryingfrom0to63,and withhigherscoresrepresentingmoreseveresymptoms.13,14
Anxiety symptoms were evaluated through the HAM-A, a questionnaireappliedbytheinterviewer validatedto Por-tuguese,with13self-reportingdomainsandonedomainof interviewerimpression,withvaryingscoresfrom0to56,and withhigherscoresrepresentingmoreseveresymptoms.15,20
The psychiatric evaluation of SPD impact was performed withtheCGI,appliedbytheinterviewertoassesstheimpact ofthediseaseonthepatient’slife,withscoresvaryingfrom 1(asymptomatic) to7(verysevereimpact).16 The impact
of SPD was evaluatedwith the Skin Picking Impact Scale (SPIS),aself-appliedquestionnairetranslatedtoPortuguese thatevaluatessymptomsofthelastweek usingtenitems,
withscore varyingbetween 0and50, withahigherscore representingmoresevereimpact.9
ThePIwasdevelopedbytwodermatologistswith expe-riencetreatingSPD.Inordertoevaluatelesionsthatreflect theactive habit of skin pickinginstead of scars fromold injuries, theinstrument evaluates lesions severityin four categories:excoriation; crust/bleeding;exulceration, and linearlesions.Eachcategory wasscored onaLikert scale of increasing severity from 0 to 10, taking into account theseverityofeachlesionandthenumberandsizeofthe lesions.Allthephotoswereanalyzedbythetwoblinded der-matologists,whoappliedthePItoeachimage.Imagesofthe samepatientwerescoredseparatelyandthenanarithmetic meanofallimageswascreatedbyeachevaluator.Another arithmeticmeanwascreatedusingthefinalscorethatthe specificdermatologistgavetoeachpatient,resultinginone averagescoreforeachindividual.
Statisticalanalysisandethicalconsiderations
Statistical analysis was performed using the software R 3.3.1. The data were analyzed for normal distribution using the Kolmogorov-Smirnov test. The chi-squared test wasused to compare categorical variables. Linear corre-lations were made using Spearman’scorrelation (rs). The exploratory factor analysis was performed with oblique rotation.The internal consistency of thescale was exam-ined usingCronbach’s alpha coefficient. The instrument’s structure was tested using confirmatory factor analysis, which offers a variety of tests and indices to assess the goodness-of-fit of the data. The indices used included chi-squaredgoodness-of-fitstatistics,theroot-mean-square errorofapproximation(RMSEA),andtheTucker-LewisIndex (TLI), and asrecommended by current literature, a good modelwasconsideredtohaveanRMSE<0.06,achi-squared goodness-of-fit test with p>0.05, and a TLI>0.95.21 The
reliabilityofthePIwascalculatedusingtheinter-observer concordance, using the intraclass correlation coefficient in the two-way randomeffect model, witha single rater and absolute agreement, and with a value equal to or greaterthan0.4consideredamoderateconcordance,and a value equal to or greater than 0.8 considered a per-fectconcordance.22,23 The levelof significancewasset at
p<0.05.Datawerecontrolledforcomorbiddepressiveand anxioussymptoms.
Allparticipantssignedaninformedconsenttoparticipate intheresearch.Thisstudyisinaccordancewiththe Guide-linesandNormsRegulatingResearchInvolvingHumanBeings (ResolutionNo.466/12),followingtheethicalprinciplesof theDeclarationofHelsinki.Thestudywasapprovedbythe EthicsandResearchCommission(CEP)under protocolNo. 1,197,672.24
Results
The study included 63 patients. Table 1 depicts the epi-demiologicaland sociodemographic characteristics of the sample.
ThevalidationoftheSPISresultedinaCronbach’salpha of0.88.Theexploratoryfactoranalysisshowedatwo-factor scale, resulting in a RMSEA<0.00001, with chi-squared
Table1 Sociodemographicandclinicalcharacteristicsofthesample.
Totalsample(n=63)
Age(years),mean(standarddeviation) 36.30(13.72)
Femalegender,n(%) 56(88.9)
Schooling(years),mean(standarddeviation) 14.43(3.53)
Caucasian,n(%) 54(85.7) Maritalstatus,n(%) Single 33(52.4) Married 19(30.2) Religion,n(%) Catholic 21(33.3) Agnostic 14(22.2) Occupation,n(%) Working 25(39.7) Student 19(30.2)
Income(US$),median(minimum---maximum) 598.8(0---8.383.2)
Triggersituation,n(%) 21(33.3)
AgeofSPDonset,median(minimum---maximum) 14.5(4---64)
Previoustreatment,n(%)
None 38(60.3)
Medication 11(17.5)
FamilyhistoryofSPD,n(%) 16(25.4)
Familyhistoryofpsychiatricdisease,n(%) 26(41.3)
Comorbidities,n(%)
Currentdepressiveepisode 16(25.4)
Pastdepressiveepisode 13(20.6)
Dysthymia 4(6.3)
Bipolaraffectivedisorder 6(9.5)
Panicdisorder 18(28.6)
Agoraphobia 10(15.9)
Socialanxiety 6(9.5)
Obsessivecompulsivedisorder 2(3.2)
Post-traumaticstressdisorder 3(4.8)
Alcoholdependence 1(2)
Nervousbulimia 2(3.2)
Generalizedanxietydisorder 25(39.7)
Psychotropictreatment,n(%)
Selectiveserotoninreuptakeinhibitor 25(39.68)
Dualantidepressant 8(12.69)
Tricyclicantidepressant 2(3.17)
Atypicalantidepressant(trazodoneandbupropion) 2(3.17)
Moodstabilizer 9(14.28)
Benzodiazepines/hypnotics 5(7.93)
Antipsychotics 4(6.34)
Methylphenidate 1(1.58)
Clinicalscales
SPIS,median(minimum---maximum) 27.5(3---48)
CGI,median(minimum---maximum) 5(2---7)
BDI,mean(standarddeviation) 15.66(10.65)
HAM-A,mean(standarddeviation) 28.41(14.68)
SPD,skinpickingdisorder;SPIS,SkinPickingImpactScale;CGI,ClinicalGlobalImpression;BDI,BeckDepressionInventory;HAM-A, HamiltonAnxietyScale.
Instructions: Make a mark next to all the phrases you find that are true for you. For those that are true, please note the degree of severity (0−5) in the last week.
None Mild Severe 0 1 2 3 4 5 1. I do not look people in the eye because of the act of
injuring my own skin.
2. I think my social life would be better if I did not injur emy skin.
3. I hate my appearance because of the act of injuring my own skin.
4. I take longer to leave home because of theact of injuring my own skin.
5. I feel embarrassed becauseof the act of injuring my own skin.
6. There are some things I cannot do because of the act of injuring my own skin.
7. I do not feel attractive because of the act of injuring my own skin.
8. I take more time than the others to get ready in the morning because of the act of injuring my own skin. 9. I do not like people looking at me because of the act of injuring my own skin.
10. My relationships have suffered because of the act of injuring my own skin.
Figure1 SkinPickingImpactScalevalidatedforBrazilianPortuguese.
Instructions:For each item, choose a Likert scale score from 0 to 10, with “0” being the lowest severity and “10” being the highest severity.
1.Active excoriation: 0 1 2 3 4 5 6 7 8 9 10 2. Crust/bleeding: 0 1 2 3 4 5 6 7 8 9 10 3. Exulceration: 0 1 2 3 4 5 6 7 8 9 10
4. Linear lesions:
0 1 2 3 4 5 6 7 8 9 10
Figure2 Photographicinstrumenttoassessskinlesionscausedbyskinpickingdisorder.
goodness-of-fittest=21.61;p<0.71,andTLI=1.034.Fig.1 showsthetranslatedSPIS.
ThePIcreatedbythetwoexpertsisshowninFig.2. Cron-bach’salphawas0.87andthereliabilitywasmoderate,with intra-class correlation of 0.6. Table 2 shows the detailed informationabout thePIscoresandreliabilityvalues.The exploratoryfactoranalysisfoundaone-factormodel,with
thesub-item‘ActiveExcoriation’havingthelargestfactorial load,of0.978.
Analyzingthecorrelationbetweentheinstruments,the SPISwascorrelatedwiththeanxiousanddepressive symp-tomsevaluatedbytheHAM-AandBDIscales.However,the PIwasnotcorrelatedwiththeCGI,norwithcomorbid symp-toms(Table3).
Table2 Meanphotographicinstrumentscoresofthesampleandtheirintra-classcorrelationbetweenevaluators.
Item Evaluator1 Evaluator2 ICC ICC(95%)
Activeexcoriation 2.4 2.83 0.718 [0.559;0.825]
Crust/bleeding 1.06 1.76 0.489 [0.196;0.687]
Exulceration 0.72 1.6 0.438 [0.091;0.666]
Linearlesions 0.37 0.53 0.522 [0.305;0.688]
Totalscore 1.15 1.69 0.661 [0.319;0.823]
ICC,intra-classcorrelation;ICC(95%),intra-classcorrelationanditsconfidenceinterval.
Table3 Spearman’scorrelationbetweeninstruments.
Scale CGI SPIS HAM-A BDI PI
CGI 1 0.69a 0.5a 0.66a 0.1
SPIS 1 0.53a 0.61a 0.11
HAM-A 1 0.78a 0.02
BDI 1 0.11
CGI,ClinicalGlobalImpression;SPIS,SkinPickingImpactScale; HAM-A,HamiltonAnxietyScale;BDI,BeckDepressionInventory; PI,photographicinstrument.
ap-Value<0.05.
Evaluating patients according to the regionof lesions, thosewithlesionsinthefacetendtohaveahigherCGIscore thanpatientswithout,butthisdidnotreachstatistical sig-nificance(mean=4.95,SD=1.22vs.mean=4.32,SD=1.29;
p=0.08).
Discussion
This study validated the SPIS to be used in the Brazilian Portugueseversion asa reliableinstrument. The SPISis a self-applied instrumentthat does notdepend on clinician knowledge about SPD. Although SPD is aprevalent condi-tion,manycliniciansarenotfamiliarizedwiththisdiagnosis andinmanycasesnon-psychiatricprofessionalsarethefirst soughtbypatients,leadingtounderestimationinthe diag-nosisandimpactonlifeofSPD.Havingaself-appliedscale abletobeusedbyallhealthprofessionalsis areasonable waytoincreasetheassessmentofSPDdiagnosisand sever-ity,overcomingthebarrieroflowreferraltotreatment.1,4
Inordertoassessskin-pickinglesionsinanobjectiveway, twodermatologistscreatedthePI,measuringSPDbasedon severityoftheactivelesionsinthe skin.To date,despite havingmany scales toassess SPD, there is no instrument todirectly evaluate the lesionscaused by thehabit. It is knownthat patients can cause severe lesions, sometimes usingobjectstomanipulatetheskin,leadingtoinfections and in more extreme cases septicemia and death.25 The
lesionseverityisnotalwaysassociatedwiththeimpacton lifeof SPD, aspatientswithsmalllesionsin the facecan havehigherscoresontheSPISthanpatientswithextensive coveredlesions.10 The PI created in this study can be an
appropriateinstrumenttoassesslesionsfromSPD, improv-ingthediagnosisofseverelesionsnotassessedbyexisting scales and facilitating earlier treatment. This instrument waseasilyappliedbydifferentevaluators.
Asexpected,theBrazilianPortugueseversionoftheSPIS hadapositivecorrelationwiththepatients’globalclinical
statusandtheirdepressiveandanxioussymptoms.Thehigh ratesofpatientswithdepressiveand/oranxioussyndromes in this study reflect the high rates of comorbidity of SPD anddepression/anxiety.ThePI createdhadnocorrelation withcomorbidsymptoms,theglobalclinicalstatus,northe SPIS,suggestingthattheseverityoflesionisnotassociated withindividuallife impact. Indeed,dermatologistsof this studytended tounderestimatetheseverityofSPDimpact whenevaluatingonlyskinlesions.Althoughnotstatistically significant, this study found a more severe global clinical conditioninthosepatientswithmoreexposedlesions, inde-pendentofthelesionseverity,whichisinaccordancewith literature.10
Thepresentresultsshouldbeinterpretedinlightofsome limitations.Thesamplewascollectedthroughadvertising, whichmayhavegeneratedaselectionbias,aspatientswith low SPD life impact, despite having severe lesions,might nothavefeltmotivatedtoaccessthisservice.Ontheother hand,patientswithextremelysevereSPDlifeimpact,with associatedsocialimpairment,maynothavefeltincondition tospontaneouslylookforhealthassistance.Thestrengthsof thisstudyarethesamplesize,powerfulincomparisonwith previous studies, the well-established statistical methods used,andtheinnovativefindings.22,26,27
Conclusion
The BrazilianPortugueseversion oftheSPISis avalidand reliable instrument toassess SPD severity and its impact on life in Brazilian individuals, which is easily applied by psychiatrists andnon-psychiatric clinicians. A PIto evalu-ate the severity of lesionscaused by SPD can be applied bydermatologistsandobjectivelyreflectsthelesion sever-ity,although notreflectingthesufferingoftheindividual. To improve SPD diagnosis, both instruments should be applied in the evaluation of the patient. Further studies are expected to assess the validity of the Brazilian Por-tuguese versionof the SPIS when usedtoassess response to treatment. Also, future studies should evaluate if the PI can beappliedby non-dermatologists, andifit can be a reliable way to assess the patient’s improvement after treatment.
Financial
support
AgrantwasprovidedtothefirstauthorbyThe Ministryof Education(MEC)---Fundac¸ãoCoordenac¸ãoAperfeic¸oamento dePessoaldeNívelSuperior(CAPES).
Author’s
contribution
AliceCastro MenezesXavier: Statistical analysis;approval ofthefinalversionofthemanuscript;conceptionand plan-ningofthestudy;elaborationandwritingofthemanuscript; obtaining, analyzing and interpreting the data; effective participation in research orientation; intellectual partici-pation inpropaedeuticand/or therapeutic conductof the cases studied; critical review of the literature; critical reviewofthemanuscript
Camila Maria Barbieri de Souza: Approval of the final versionofthemanuscript;conceptionandplanningof the study;obtaining,analyzingandinterpretingthedata; criti-calreviewofthemanuscript.
Luís Henrique Fernandes Flores: Approval of the final versionofthemanuscript;conceptionandplanningof the study;obtaining,analyzingandinterpretingthedata; criti-calreviewofthemanuscript.
Clarissa Prati: Conception and planning of the study; obtaining, analyzing and interpreting the data; critical reviewofthemanuscript.
Cecilia Cassal: Conception and planning of the study; obtaining,analyzingandinterpretingthedata;intellectual participationinpropaedeuticand/ortherapeuticconductof thecasesstudied.
Carolina Blaya Dreher: Statistical analysis; approval of the final version of the manuscript; conception and planning of the study; elaboration and writing of the manuscript;effectiveparticipationinresearchorientation; intellectualparticipationinpropaedeuticand/or therapeu-tic conduct of the cases studied; critical review of the manuscript.
Conflicts
of
interest
Nonedeclared.Acknowledgements
ToMEC---Fundac¸ãoCoordenac¸ãoAperfeic¸oamentode Pes-soaldeNívelSuperior(CAPES),forthegrantprovidedtothe firstauthor.ToFAPERGS(Fundac¸ãodeAmparoàPesquisado EstadodoRioGrandedoSul),forthescholarshipprovided totheauthorLuisHenriqueFernandesFlores.
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