Negative and positive affect regulation in a transdiagnostic internet-based protocol for emotional disorders: Randomized controlled trial

O iginal Pape Nega i e and Posi i e A ec Regula ion in a T ansdiagnos ic In e ne -Based P o ocol o Emo ional Diso de s: Randomized Con olled T ial Amanda Díaz-Ga cía1, PhD; Albe o González-Robles1, PhD; Azucena Ga cía-Palacios2,3, PhD; Ja ie Fe nández-Ál a ez4, MSc; Diana Cas illa3,5, PhD; Juana Ma ía B e ón2, PhD; Rosa Ma ía Baños3,5, PhD; Soledad Que o2, PhD; C is ina Bo ella2,3, PhD 1Depa men o Psychology and Sociology, Uni e sidad de Za agoza, Te uel, Spain 2Uni e si a Jaume I, Cas ellón de la Plana, Spain 3CIBER Fisiopa ología Obesidad y Nu ición (CIBERObn), Ins i u o Ca los III, Mad id, Spain 4Depa men o Psychology, Uni e si à Ca olica del Sac o Cuo e, Milan, I aly 5Depa men o Pe sonali y, E alua ion and Psychological T ea men s, Uni e sidad de Valencia, Valencia, Spain Co esponding Au ho : Amanda Díaz-Ga cía, PhD Depa men o Psychology and Sociology Uni e sidad de Za agoza Calle Cdad. Escola , S/N, 44003 Te uel Te uel, 44003 Spain Phone: 34 878618154 Email: amandadiaz@uniza .es Abs ac Backg ound: Emo ional diso de s (EDs) a e among he mos p e alen men al diso de s. Exis ing e idence-based psychological ea men s a e no su icien o educe he disease bu den o men al diso de s. I is he e o e essen ial o implemen inno a i e solu ions o achie e a success ul dissemina ion o psychological ea men p o ocols, and in his ega d, he use o in o ma ion and communica ion echnologies such as he in e ne can be e y use ul. Fu he mo e, he li e a u e sugges s ha no e e yone wi h an ED ecei es he app op ia e ea men . This si ua ion has led o he de elopmen o new in e en ion p oposals based on he ansdiagnos ic pe spec i e, which a emp s o add ess he unde lying p ocesses common o EDs. Mos o hese ansdiagnos ic in e en ions ocus p ima ily on down egula ing nega i e a ec i i y (NA), and less a en ion has been paid o s eng hs and he up egula ion o posi i e a ec i i y, despi e i s impo ance o well-being and men al heal h. Objec i e: This s udy aims o e alua e he e icacy o a ansdiagnos ic in e ne -based ea men o EDs in a communi y sample. Me hods: A 3-a med andomized con olled ial was conduc ed. A o al o 216 pa icipan s we e andomly assigned o a ansdiagnos ic in e ne -based p o ocol (TIBP), a TIBP+ posi i e a ec (PA) componen , o a wai ing lis (WL) con ol g oup. The ea men p o ocol con ained co e componen s mainly add essed o down egula e NA (ie, p esen - ocused emo ional awa eness and accep ance, cogni i e lexibili y, beha io al and emo ional a oidance pa e ns, and in e ocep i e and si ua ional exposu e) as well as a PA egula ion componen o p omo e psychological s eng hs and enhance well-being. Da a on dep ession, anxie y, quali y o li e, neu o icism and ex a e sion, and PA/NA be o e and a e ea men we e analyzed. Expec a ions and opinions o ea men we e also analyzed. Resul s: Wi hin-g oup compa isons indica ed signi ican p e-pos educ ions in he wo expe imen al condi ions. In he TIBP+PA condi ion, he e ec sizes we e la ge o all p ima y ou comes (d=1.42, Beck Dep ession In en o y [BDI-II]; d=0.91, Beck Anxie y In en o y [BAI]; d=1.27, Posi i e and Nega i e A ec Schedule-Posi i e [PANAS-P]; d=1.26, Posi i e and Nega i e A ec Schedule-Nega i e [PANAS-N]), whe eas he TIBP condi ion yielded la ge e ec sizes o BDI-II (d=1.19) and PANAS-N (d=1.28) and medium e ec sizes o BAI (d=0.63) and PANAS-P (d=0.69). Be ween-g oup compa isons e ealed ha pa icipan s who ecei ed one o he wo ac i e ea men s sco ed be e a pos ea men han WL pa icipan s. Al hough he e we e no s a is ically signi ican di e ences be ween he wo in e en ion g oups on he PA measu e, e ec sizes we e consis en ly la ge in he TIBP+PA condi ion han in he s anda d ansdiagnos ic p o ocol. J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 1h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X Conclusions: O e all, he indings indica e ha EDs can be e ec i ely ea ed wi h a ansdiagnos ic in e en ion ia he in e ne , as signi ican imp o emen s in dep ession, anxie y, and quali y o li e measu es we e obse ed. Rega ding PA measu es, p omising e ec s we e ound, bu mo e esea ch is needed o s udy he ole o PA as a he apeu ic componen . T ial Regis a ion: ClinicalT ials.go NCT02578758; h ps://clinical ials.go /c 2/show/NCT02578758 In e na ional Regis e ed Repo Iden i ie (IRRID): RR2-10.1186/s12888-017-1297-z (J Med In e ne Res 2021;23(2):e21335) doi: 10.2196/21335 KEYWORDS ansdiagnos ic; posi i e a ec i i y; nega i e a ec i i y; emo ion egula ion; emo ional diso de s; in e ne In oduc ion T ansdiagnos ic T ea men s o he Common Psychopa hological P ocesses Unde lying Emo ional Diso de s Emo ional diso de s (EDs) a e de ined as anxie y and unipola mood diso de s. These diso de s ha e been g ouped based on hei common biological and psychological ulne abili ies [1]. The es ima ed li e ime p e alence a es o EDs a e high (28.8% o anxie y diso de s and 20.8% o mood diso de s). In addi ion, he co-occu ence o mul iple EDs has also been ound o be ele a ed, wi h s udies showing ha mo e han 40% o people wi h one diagnosis also me he diagnos ic c i e ia o a second diso de o e a 12-mon h pe iod [2]. In ecen yea s, esea ch has demons a ed ha e idence-based psychological ea men s (EBTs) a e e ec i e in he ea men o EDs [3]. Howe e , he e has been li le success in dec easing he p e alence and incidence o men al illness, and only a small p opo ion o people in need ac ually ecei e adequa e psychological ea men [4]. In addi ion, dissemina ing EBTs has become a eal challenge because o hei cos , he du a ion o he ea men s, and he lack o well-quali ied p o essionals [5], which can explain why EBTs a e unde u ilized in clinical p ac ice se ings [6]. Recen ly, ansdiagnos ic app oaches ha e eme ged ha add ess he common cha ac e is ics ound in cogni i e, beha io al, emo ional, and o he dys egula ion a eas unde lying di e en EDs, ha is, he biological and psychological ulne abili ies sha ed by di e en men al diso de s [7,8]. Wi h ega d o ansdiagnos ic p ocesses, maladap i e emo ion egula ion s a egies ha e been sugges ed as po en ial explana o y ac o s unde lying he como bidi y ac oss EDs [9]. In esponse o ansdiagnos ic app oaches, se e al ansdiagnos ic ea men s ha e been de eloped o p o ide pa ien s wi h a se o skills gea ed speci ically owa d common ulne abili ies [10]. One example o hese ea men s is he Uni ied P o ocol (UP) [7], which was designed o be applicable ac oss di e en EDs and ep esen ed a signi ican shi owa d ansdiagnos ic psychological ea men s o EDs [11,12]. The UP has been es ed and esul s indica e ha i is e ec i e in educing nega i e a ec (NA) [13], wi h imp o emen s main ained a he 18-mon h ollow-up [14]. Fu he mo e, he e ec o he UP has been shown on he wo empe amen dimensions o neu o icism (N)/beha io al inhibi ion (BI) and ex a e sion (E)/beha io al ac i a ion (BA) [15]. Moun ing e idence demons a es he e icacy o ansdiagnos ic ea men s in pa ien s wi h EDs compa ed wi h con ol g oups [16-19], showing ha ansdiagnos ic ea men s a e jus as e ec i e as diso de -speci ic cogni i e beha io al he apy (CBT) [12,20]. The da a sugges ha a ansdiagnos ic ea men o EDs migh be mo e widely e ec i e ac oss a di e se ange o men al diso de s, add essing di e en diso de s wi h a single p o ocol [21]. Mo e speci ically, a ecen me a-analysis showed ha he UP is mo e e ec i e compa ed wi h di e en con ol g oups, such as ea men as usual, wai lis , and medica ion con ol g oups, in ea ing anxie y and dep essi e symp oms [22]. The Role o Posi i e A ec in EDs Rega ding he empe amen al ulne abili ies, some au ho s ha e iden i ied wo essen ial dimensions o empe amen in he e iology and cou se o EDs: N/NA and E/posi i e a ec (PA) [8]. Hence, neu o icism has been iden i ied as a co e ac o in ol ed in he de elopmen o EDs [23]. In addi ion, N/NA and E/PA ha e been closely ela ed o G ay’s (1987) cons uc s o BI and BA, espec i ely [24-26], and hese e ms a e o en used in e changeably as he mos s able measu es o empe amen [8,15,26,27]. Thus, people wi h EDs ha e highe le els o N/NA/BI [8], and hey expe ience nega i e emo ions mo e in ensely and equen ly [28] han people who do no ha e any ED. In con as , he dimension o posi i e emo ionali y, E/PA/BA, has also been obse ed in many diso de s, sugges ing ha people wi h an ED show low le els o E/BA [29], which can p edic he onse o dep ession [30] and inc ease he se e i y o he p oblem [31]. Despi e he impo ance o PA in heal h and well-being, he e is limi ed esea ch on i s p omo ion; he e o e, mo e esea ch is needed in his a ea. Fu he mo e, no wi hs anding he ecen upsu ge in ansdiagnos ic ea men s o EDs, mos o hese p o ocols ha e ocused on educing NA. They ha e add essed co e psychopa hological de ici s in he way pa ien s expe ience and espond o nega i e emo ions [32]. Howe e , less a en ion has been paid o posi i e emo ions o p omo ing PA [33]. In addi ion o being in ol ed in he symp oma ology o EDs, posi i e emo ionali y is conside ed a co e elemen o men al heal h, showing bene icial, gene alized e ec s on heal h and unc ioning [34-37]. Thus, he ela ionship be ween emo ion egula ion (eg, cogni i e eapp aisal) and well-being has also been demons a ed [38]. On he basis o he li e a u e ha highligh s he po en ial impo ance o posi i e emo ionali y as a ea men componen [39-43], i is necessa y o de elop and es ea men componen s ocused on up egula ing PA. J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 2h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X In e ne -Based T ea men s The e a e many models o deli e ing in e en ions in no el ways ha can be scaled up o each la ge numbe s o people in need [4]. In his ega d, in o ma ion and communica ion echnologies (ICTs) play an impo an ole and can acili a e he a ailabili y o EBTs [44]. Speci ically, he in e ne is used o he assessmen and ea men o clinical condi ions, and i has been es ablished as a use ul and e ec i e ool o deli e ing psychological ea men s o ea se e al psychological diso de s [45], pa icula ly dep ession and anxie y diso de s [46]. Mo eo e , some me a-analyses ha e e ealed ha hese in e en ions a e as e icacious as ace- o- ace adi ional ea men s [47,48]. This S udy The pu pose o his s udy is o es he e icacy o a web-based psychological ea men p o ocol o indi iduals om a communi y sample wi h one o mo e diagnoses o EDs: majo dep essi e diso de (MDD), dys hymic diso de (DD), obsessi e-compulsi e diso de , and ou anxie y diso de s: panic diso de (PD), ago aphobia (AG), gene alized anxie y diso de (GAD), social anxie y diso de (SAD), anxie y diso de no o he wise speci ied, and (unipola ) mood diso de no o he wise speci ied [49]. Ra he han ocusing solely on NA, he ea men p o ocol includes 2 ypes o componen s: one based on classical pe spec i es o down egula ing NA and he o he aimed a up egula ing PA. The p o ocol can be applied ei he in i s adi ional o ma ( ansdiagnos ic in e ne -based p o ocol, TIBP) o by including bo h o hese componen s (TIBP+PA). Some s udies ha e es ed he e icacy o ansdiagnos ic in e en ions in imp o ing PA measu es. Howe e , hese s udies do no include a speci ic componen o add ess PA egula ion [13], o hey a e uncon olled ials [50-52]. Only one s udy ha e alua ed he e icacy o a new ansdiagnos ic ea men ocuses on PA, bu i is a pilo s udy a he han a andomized con olled ial (RCT) [53]. To he bes o ou knowledge, no published RCT has es ed he e icacy o a ansdiagnos ic in e ne -based ea men o EDs wi h a speci ic componen o add ess PA egula ion. The e o e, he aim o his s udy is o in es iga e he e ec i eness o his ansdiagnos ic p o ocol o EDs, wi h and wi hou he speci ic componen o up egula e PA, e sus a wai -lis con ol g oup. A seconda y aim is o es he di e en ial e ec o he speci ic ea men componen designed o up egula e PA. Finally, we s udy pa ien s’ accep ance o he p og am de eloped o apply he ea men p o ocol o e he in e ne wi h minimal suppo by he clinician. We hypo hesized ha (1) bo h sel -applied p o ocol modali ies (TIBP and TIBP+PA) would be mo e e ec i e han he wai -lis con ol condi ion in he ea men o EDs; (2) bo h in e en ions would esul in signi ican imp o emen s in dep essi e and anxious symp oma ology a pos ea men ; (3) he TIBP+PA would signi ican ly ou pe o m he TIBP g oup on PA measu es; and (4) bo h p o ocols a e well accep ed, wi h no s a is ical di e ences be ween condi ions. Me hods S udy Design This s udy was a h ee-a med supe io i y RCT in which pa icipan s we e andomly alloca ed o 1 o 3 condi ions: (1) TIBP, (2) TIBP+PA, and (3) wai ing lis (WL) con ol condi ion. Fo e hical easons, pa icipan s in he con ol condi ion we e o e ed he possibili y o ecei ing he ea men p o ocol a e spending ime on he WL (16 weeks), hus lea ing no con ol g oup o he ollow-up measu emen s. Block andomiza ion was pe o med o ensu e ha all p ima y diagnoses we e equally ep esen ed ac oss condi ions. The ial was egis e ed a ClinicalT ial.go as NCT02578758 on Oc obe 16, 2015. The s udy was app o ed by he E hics Commi ee o Uni e si a Jaume I (Cas ellón, Spain; May 5, 2016) and was conduc ed in compliance wi h he s udy p o ocol, ollowing he Consolida ed S anda ds o Repo ing T ials (CONSORT) s a emen [54], he CONSORT-eHeal h guidelines [55], and he S anda d P o ocol I ems: Recommenda ions o In e en ional T ials guidelines [56,57]. De ails o he s udy p o ocol ha e been epo ed elsewhe e [58]. Di e en e ec sizes ound in he li e a u e based on he ansdiagnos ic pe spec i e o EDs we e conside ed o es ima e he s udy powe in his s udy. These calcula ions we e pe o med wi h he so wa e p og am G*Powe 3.1 [59] and published in he s udy p o ocol [58]. This s udy epo s on p e- o pos ea men da a. S udy Popula ion, Rec ui men , and Eligibili y C i e ia The clinical ial was conduc ed in a communi y sample o indi iduals diagnosed wi h one o mo e o he a o emen ioned diso de s. Pa icipan s we e ec ui ed om adul olun ee s in e es ed in pa icipa ing in he s udy be ween June 2015 and July 2018. Po en ial pa icipan s we e a ended by phone by he clinical eam membe s (who had a leas a uni e si y mas e ’s deg ee in gene al heal h psychology) o explain he s udy and cla i y any doub s. People in e es ed in pa icipa ing signed he web-based in o med consen o m and we e assessed aking in o accoun all he inclusion c i e ia. The inclusion c i e ia we e as ollows: (1) being a leas 18 yea s old; (2) mee ing he Diagnos ic and S a is ical Manual o Men al Diso de s, Fou h Edi ion (DSM-IV) diagnos ic c i e ia o EDs; (3) ha ing he abili y o unde s and and ead Spanish; (4) ha ing access o he in e ne and an email add ess; and (5) p o iding web-based in o med consen . The exclusion c i e ia we e as ollows: (1) ha ing schizoph enia, bipola diso de , o alcohol and/o subs ance dependence diso de ; (2) p esence o a high isk o suicide (de ined by he Mini-In e na ional Neu opsychia y In e iew [60] as g ea e han o equal o 10 poin s); (3) p esence o medical disease/condi ion ha p e en s he pa icipan om ca ying ou he psychological ea men ; and (4) ecei ing ano he psychological ea men du ing he s udy. Recei ing pha macological ea men was no an exclusion c i e ion, bu any inc ease and/o change in he medica ion (in he case o ecei ing) du ing he s udy pe iod implied he pa icipan ’s exclusion om subsequen analyses. Pa icipan s who ul illed all he s udy c i e ia we e andomized o one o he h ee expe imen al condi ions by an independen esea che . This esea che was unawa e o he cha ac e is ics o he s udy and had no clinical in ol emen in he ial o access o he s udy J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 3h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X da a. Pa icipan s ag eed o pa icipa e be o e de e mining which ea men hey we e alloca ed. All pa icipan s we e ee o wi hd aw om he ea men a any ime. Access and pa icipa ion in he s udy did no in ol e paymen in any case. The T ansdiagnos ic In e en ions The ea men p o ocol is based on he ansdiagnos ic pe spec i e de i ed om he UP [5,7] and some s a egies om Ma sha Linehan’s p o ocol [61]. Ini ially, a manualized p o ocol was de eloped and s uc u ed in a pa ien and he apis handbook. La e , he p o ocol was adap ed o a mul imedia web pla o m ( ideos, igne es, audios, images, e c) o be comple ely sel -applied ia he in e ne [62] h ough a PC o a able . The ease o use o he p og am has been s eng hened because i p esen s a linea na iga ion o op imize he ea men s uc u e and make he ea men easie and mo e a ac i e o he pa icipan s. The p og am consis s o an assessmen p o ocol and a ea men p o ocol ha includes co e componen s, mainly designed o down egula e NA (p esen - ocused emo ional awa eness and accep ance, cogni i e lexibili y, beha io al and emo ional a oidance pa e ns, and in e ocep i e and si ua ional exposu e) and up egula e PA o p omo e psychological s eng hs and enhance well-being [63]. The p o ocol con en is adap ed om he UP [7] and some o he s a egies o emo ion egula ion om dialec ical beha io he apy [61]. The PA egula ion componen is based mainly on BA s a egies [64], s a egies o p omo e pleasan and signi ican ac i i ies linked o alues and li e goals, and s a egies o enhance pe sonal s eng hs, posi i e eelings, posi i e cogni ions, and posi i e beha io [63,65]. Fu he mo e, well-being he apy s a egies [66,67] and some concep s om F edickson’s B oaden-and-Build Theo y [68] a e also included in he p og am. The PA egula ion componen akes place a e he NA egula ion componen . The p o ocol also includes adi ional he apeu ic componen s o e idence-based ea men o ED (psychoeduca ion, mo i a ion o change, and elapse p e en ion). All he ea men componen s we e de eloped h ough wo sel -applied p o ocol modali ies (TIBP and TIBP+PA) wi h 12 and 16 modules, espec i ely, wi h he only di e ence being he inclusion o absence o he modules ha con ain he PA- egula ion componen . A de ailed desc ip ion o modules ha con ain he PA egula ion componen is p esen ed in Mul imedia Appendix 1[64,66,68-77]. The modules in each in e en ion p o ocol a e desc ibed b ie ly elsewhe e [58]. The du a ion o he p og am could a y among use s, and pa icipan s in bo h ea men condi ions had equal access o he p o ocol o a maximum pe iod o 18 weeks. The p og am sen weekly messages o he pa ien o emind him/he o con inue o wo k o bene i om he p og am. A p o essional pla o m was used o send hese messages [78]. The p og am also sen au oma ic emails wi h eminde s o access he modules when pa icipan s had no en e ed he pas 15 days. In addi ion o his ICT suppo , human suppo was also p o ided h ough weekly phone calls (maximum o 5 min) du ing he ea men pe iod o esol e any di icul ies o doub s, o o emind hem o he impo ance o e iewing he ea men con en s. Ou come Measu es The assessmen p o ocol was included a he beginning and end o he web-based p og am. A de ailed desc ip ion o he measu es and hei aims has been published elsewhe e [58]. The measu es included in his s udy a e desc ibed in Table 1. J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 4h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X Table 1. S udy measu es. Time o assessmen ωa C onbach αAimMeasu e Diagnos ic in e iew BLd N/A N/Ac Psychia ic diagnosis MINIb P ima y ou comes BL, Pos -T 0.91.91Se e i y o dep ession BDI-IIe BL, Pos -T0.92.92Se e i y o anxie y BAIg BL, Pos -TPA=0.91; NA=0.89 PAi=.91; NAj=.89 Posi i e and nega i e a ec PANASh Seconda y ou comes Pe sonali y measu es BL, Pos -TN=0.82; E=0.84 Nl=.81; Em=.84 Neu o icism and ex a e sion NEO FFIk Quali y o li e BL, Pos -T0.70.67Heal h- ela ed quali y o li e EQ-5Dn Expec a ion and opinion BLN/AN/AExpec a ion o ea men Expec a ion o ea men scale Pos -TN/AN/AOpinion o ea men Opinion o ea men scale aω: coe icien omega in his s udy. bMINI: Mini-In e na ional Neu opsychia ic In e iew, Ve sion 5.0.0. cN/A: no applicable. dBL: baseline. eBDI-II: Beck Dep ession In en o y-II. Pos -T: pos ea men . gBAI: Beck Anxie y In en o y. hPANAS: Posi i e and Nega i e A ec Schedule. iPA: posi i e a ec . jNA: nega i e a ec . kNEO FFI: NEO Fi e Fac o In en o y. lN: neu o icism. mE: ex a e sion. nEQ-5D: Eu oQoL-5D Ques ionnai e. S a is ical Analysis G oup di e ences in pa icipan s’sociodemog aphic and clinical da a a baseline we e examined o con i m ha hey we e compa able a e andomiza ion. One-way analysis o a iance o con inuous a iables and Fishe exac es s o independence o ca ego ical a iables we e used. In en ion- o- ea (ITT) using mixed models, wi h ull in o ma ion maximum likelihood es ima ion and wi hou any ad hoc impu a ions we e conduc ed o handle missing da a due o pa icipan d opou [79]. This app oach uses all a ailable da a, does no subs i u e missing alues wi h assumed o es ima ed alues, and does no assume ha he las measu emen is s able ( he las obse a ion ca ied o wa d assump ion) [80]. Mixed model analyses a e app op ia e o RCTs wi h mul iple ime poin s and p e- o pos only designs wi h subs an ial d opou a es [81]. The pa e n o missingness was in es iga ed o de e mine i s likelihood o being andom a he han sys ema ic (missing no a andom, MNAR). Subsequen ly, associa ions be ween sample cha ac e is ics missingness in he ou come a iables we e examined ( es s o con inuous a iables and Fishe exac es s o ca ego ical a iables). A linea mixed model o each ou come measu e was implemen ed using he linea mixed-e ec s models (MIXED) p ocedu e wi h one andom in e cep pe subjec . An iden i y co a iance s uc u e was speci ied o model he co a iance s uc u e o he andom in e cep . Signi ican e ec s we e ollowed up wi h pai wise compa isons using he Bon e oni co ec ion. E ec sizes we e calcula ed o wi hin- and be ween-g oup compa isons using he s anda dized obse ed mean di e ence p oposed by Cohen [82]. To de e mine he exis ence o a eliable change in a pa ien , he eliable change index (RCI; Jacobson and T uax’s me hod) [83] was used. The RCI alues o he p ima y ou comes (Beck Dep ession In en o y, BDI-II; Beck Anxie y In en o y, BAI; Posi i e and Nega i e A ec Schedule-Posi i e [PANAS-P]; and Posi i e and Nega i e A ec Schedule-Nega i e [PANAS-N]) we e calcula ed o he comple e sample (pa icipan s who p o ided da a a pos ea men ). Fishe exac es s we e pe o med o e alua e g oup di e ences in RCI a es o comple e s. All s a is ical analyses we e conduc ed using IBM SPSS S a is ics J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 5h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X o Windows, e sion 22, and SAS so wa e, e sion 9.4, o he SAS Sys em o Windows. Resul s Pa icipan Flow and A i ion Ou o he 573 people who exp essed ini ial in e es in he s udy, as he low diag am shows (Figu e 1), only 402 pe o med he ini ial in e iew. A his s age, 186 pa icipan s ailed o mee he inclusion c i e ia. Finally, 216 pa ien s we e included in he s udy, and hey we e andomly alloca ed o each expe imen al condi ion: TIBP, n=71; TIBP+PA, n=73; WL, n=72. Rega ding p e ea men assessmen s, 71 pa icipan s pe o med i in he TIBP, 73 in he TIBP+PA, and 72 in he WL. A simila numbe o pa icipan s pe o med he pos ea men assessmen om bo h in e en ion condi ions (TIBP, n=45; TIBP+PA, n=46). No signi ican di e ences be ween he h ee condi ions we e ound in d opou a es (X22=3.8, P=.14). In he TIBP condi ion, o hose who s a ed he p og am (n=71), 26 pa icipan s (26/71, 37%) wi hd ew om he ea men . In he TIBP+PA condi ion, a simila pa e n was ound; o hose who s a ed he p og am (n=73), 27 pa icipan s (27/73, 37%) wi hd ew om he ea men . Finally, in he WL con ol g oup, da a om 55 pa icipan s we e ob ained a e hey had spen 16 weeks on he WL (55/72, 76% e en ion; 17/72, 24% d opou ). O e all, o he 216 pa icipan s who s a ed he s udy, 86 pa icipan s wi hd ew om he p og am. As a esul , wo pa e ns o missingness eme ged. One o hem ep esen ed 32% o he sample (70/216, 32.4%) and he o he ep esen ed a e y low pe cen age (16/216, 7.4%). Missingness was no ela ed o he cha ac e is ics lis ed in Table 2 in any o he h ee a ms o he RCT (all P>.05 in bo h pa e ns). The e o e, pa e ns o missingness we e no ound o be MNAR and he decision o con inue he analysis wi h he a ailable da a was made [84,85]. Figu e 1. Flowcha o pa icipan s. DSM-IV-TR: Diagnos ic and S a is ical Manual o Men al Diso de s, Fou h Edi ion, Tex Re ision; ED: emo ional diso de ; TIBP: T ansdiagnos ic in e ne -Based P o ocol; PA: posi i e a ec ; WL: Wai ing Lis ; ITT: in en ion- o- ea . J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 6h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X Table 2. Demog aphic cha ac e is ics o pa icipan s a p e-assessmen (N=216). P alueS a is icd To al (N=216)WLc(n=72)TIBP+PAb(n=73)TIBPa(n=71)Va iable .09F2213=2.38233.57 (11.24); 18-72 31.82 (10.50); 19-58 33.11 (9.74); 19-5235.82 (13.04); 18-72 Age (yea s), mean (SD); ange .88 X22=0.2 Sex, n (%) 155 (71.8)53 (74)51 (70)51 (72)Female 61 (28.2)19 (26)22 (30)20 (28)Male .97 N/Ae Ma i al s a us, n (%) 127 (58.8)42 (58)41 (56)44 (62)Single 75 (34.7)25 (35)27 (37)23 (32)Ma ied o pa ne ed 14 (6.5)5 (7)5 (7)4 (6)Di o ced o widowed .46N/AEduca ion le el, n (%) 9 (4.2)3 (4)5 (7)1 (1)Basic s udies 44 (20.4)17 (24)12 (16)15 (21)Medium s udies 163 (75.5)52 (72)56 (77)55 (78)Highe s udies .57N/AP incipal diagnosis, n (%) 36 (16.7)16 (22)9 (12)11 (15) MDD 3 (1.4)2 (3)0 (0)1 (1) DDg 71 (32.9)24 (33)21 (29)26 (37) GADh 16 (7.4)6 (8)6 (8)4 (6) PDi/AGj 9 (4.2)3 (4)4 (6)2 (3)PD 13 (6.0)1 (1)6 (8)6 (9)AG 54 (25.0)16 (22)23 (32)15 (21) SADk 6 (2.8)2 (3)1 (1)3 (4) OCDl 7 (3.2)1 (1)3 (4)3 (4) Anxie y NOSm 1 (0.5)1 (1)0 (0)0 (0)Dep ession NOS .17N/ANumbe o como bid diso de s, n (%) 81 (37.5)34 (47)19 (26)32 (45)0 92 (42.6)26 (36)36 (49)28 (39)1 57 (62)15 (57)22 (61)18 (64)MDD 6 (7)3 (12)2 (6)1 (4)DD 11 (12)2 (8)7 (19)2 (7)GAD 0 (0.0)0 (0)0 (0)0 (0)PD/AG 1 (1)1 (4)0 (0)0 (0)PD 7 (8)2 (8)2 (6)3 (11)AG 10 (10)3 (11)3 (8)4 (14)SAD 0 (0)0 (0)0 (0)0 (0)OCD 0 (0)0 (0)0 (0)0 (0)Anxie y NOS 0 (0)0 (0)0 (0)0 (0)Dep ession NOS 27 (12.5)7 (10)12 (16)7 (10)2 7 (26)2 (29)3 (25)2 (29)MDD and GAD 3 (11)1 (14)1 (8)1 (14)MDD and PD/AG J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 7h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X P alueS a is icd To al (N=216)WLc(n=72)TIBP+PAb(n=73)TIBPa(n=71)Va iable 4 (15)2 (29)1 (8)1 (14)MDD and PD 3 (11)0 (0)2 (17)0 (0)MDD and AG 1 (4)0 (0)0 (0)1 (14)MDD and OCD 1 (4)0 (0)1 (8)0 (0)DD and SAD 4 (15)1 (14)1 (8)2 (29)GAD and SAD 2 (7)0 (0)2 (17)0 (0)GAD and AG 1 (4)1 (14)0 (0)0 (0)PD/AG and SAD 1 (4)0 (0)1 (8)0 (0)SAD and OCD 16 (7.4)5 (7)6 (8)4 (6)3 4 (25)2 (40)1 (17)1 (25)MDD, GAD, and AG 4 (25)2 (40)2 (33)0 (0)MDD, GAD, and SAD 2 (13)0 (0)1 (17)0 (0)MDD, GAD, and OCD 2 (13)0 (0)2 (33)0 (0)MDD, PD, and SAD 1 (6)1 (20)0 (0)0 (0)MDD, PD, and OCD 1 (6)0 (0)0 (0)1 (25)MDD, AG, and SAD 1 (6)0 (0)0 (0)1 (25)MDD, SAD, and OCD 1 (6)0 (0)0 (0)1 (25)GAD, PD/AG, and SAD aTIBP: ansdiagnos ic in e ne -based p o ocol. bTIBP+PA: ansdiagnos ic in e ne -based p o ocol+posi i e a ec componen . cWL: wai ing lis . dS a is ic: Pea son chi-squa e o Fishe exac es . eN/A: no applicable. MDD: majo dep essi e diso de . gDD: dys hymic diso de . hGAD: gene alized anxie y diso de . iPD: panic diso de . jAG: ago aphobia. kSAD: social anxie y diso de . lOCD: obsessi e-compulsi e diso de . mNOS: no o he wise speci ied. Baseline Da a and Pa icipan Cha ac e is ics De ails abou pa icipan s’ sociodemog aphic cha ac e is ics o each g oup a p e ea men a e p esen ed in Table 2. The esul s indica ed ha he e we e no signi ican di e ences be ween he expe imen al g oups be o e ea men o any o hese a iables, indica ing ha he andomiza ion was success ul. O e all, pa icipan s’ mean age was 33.57 yea s (SD 11.24, ange 18-72), he majo i y we e emales (155/216, 71.8%), and mos o hem we e single (127/216, 58.8%) and had comple ed o we e pu suing highe s udies (163/216, 75.5%; eg, unde g adua e deg ee s udies, g adua e s udies o uni e si y mas e ’s deg ees, o pos g adua e s udies o doc o al deg ees). P incipal and como bid diagnoses a e p esen ed in Table 2. Mos o he pa icipan s had GAD (71/216, 32.9%), ollowed by SAD (54/216, 25.0%) and MDD (36/216, 16.7%). Rega ding he pa e ns o como bidi y in he sample, 41.7% (90/216) o he pa icipan s had a leas one como bid diagnosis, wi h MDD being he mos common como bid diso de (n=57), ollowed by GAD (n=11), SAD (n=10), AG (n=7), DD (n=6), and PD (n=1). Rega ding he clinical cha ac e is ics o he pa icipan s in each expe imen al condi ion a p e ea men (Table 3), no s a is ically signi ican di e ences we e ound be ween he g oups on any o he p ima y and seconda y ou comes. J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 8h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X Table 3. Clinical cha ac e is ics o pa icipan s a p e-assessmen . P alueS a is ic, F(d )To al (N=216), mean (SD) WLc(n=72), mean (SD) TIBP+PAb(n=73), mean (SD) TIBPa(n=71), mean (SD) Measu e P ima y ou comes .141.966 (2213)26.93 (11.76)26.31 (12.43)29.07 (11.33)25.35 (11.33) BDI-IId .490.719 (2,197)22.23 (12.04)21.87 (12.56)23.58 (11.50)21.14 (12.10) BAIe .281.277 (2213)19.84 (6.22)19.28 (5.67)19.32 (6.22)20.72 (6.52) PANAS _Posi i e .062.807 (2213)30.43 (8.61)28.63 (9.03)31.96 (8.79)30.68 (7.73)PANAS_Nega i e Seconda y ou comes Pe sonali y measu es .062.853 (2213)32.36 (7.78)31.39 (8.20)34.11 (8.18)31.54 (6.65) NEO FFIg_Neu o icism .141.991 (2213)20.84 (8.39)21.79 (8.66)19.26 (7.59)21.49 (8.77)NEO FFI_Ex a e sion Quali y o li e .600.511 (2197)53.75 (18.44)51.91 (17.81)54.78 (19.75)54.60 (17.76) EQ-5Dh aTIBP: ansdiagnos ic in e ne -based p o ocol. bTIBP+PA: ansdiagnos ic in e ne -based p o ocol+posi i e a ec componen . cWL: wai ing lis . dBDI-II: Beck Dep ession In en o y-II. eBAI: Beck Anxie y In en o y. PANAS: Posi i e and Nega i e A ec Schedule. gNEO FFI: NEO Fi e Fac o In en o y. hEQ-5D: Eu oQoL-5D ques ionnai e. E ec i eness o he In e en ion on P ima y and Seconda y Ou comes a P e-Pos P ima y Ou comes Table 4 includes desc ip i e s a is ics (ie, means and SD) o TIBP+PA, TIBP, and WL a p e ea men and pos ea men ; Table 5 includes wi hin-g oup and be ween-g oup e ec sizes and CIs o all he p ima y ou come measu es in he h ee expe imen al g oups, based on he ITT sample. Fo he h ee p ima y ou comes, wi hin-g oup compa isons indica ed signi ican p e-pos educ ions in he wo expe imen al condi ions, wi h la ge e ec sizes o he BDI-II (d=1.19) and PANAS-N (d=1.28), and mode a e e ec sizes o he BAI (d=0.63) and PANAS-P (d=0.69) in he TIBP condi ion. In he TIBP+PA condi ion, he e ec sizes we e la ge o all p ima y ou comes (d=1.42, BDI-II; d=0.91, BAI; d=1.27, PANAS-P; d=1.26, PANAS-N). Be ween-g oup compa isons e ealed ha pa icipan s who ecei ed he ea men sco ed be e a pos ea men han he WL g oup. G ea e educ ions we e ound in he BDI-II sco es in he TIBP condi ion han in he WL condi ion (mean di e ence −13.61; P<.001; d=1.18; 95% CI −1.61 o −0.76), as well as be ween he TIBP+PA condi ion and WL (mean di e ence −14.31; P<.001; d=1.05; 95% CI −1.46 o −0.63), wi h la ge e ec sizes. No di e ences we e ound be ween he wo expe imen al condi ions (mean di e ence 0.70; P=.76; d=0.10; 95% CI −0.51 o −0.31).The esul s o BAI sco es we e simila o he pa e n o indings o he BDI: g ea e educ ions in he TIBP condi ion (mean di e ence −8.19; P=.001; d=0.63; 95% CI −1.07 o −0.20) and TIBP+PA condi ion (mean di e ence −9.28; P<.001; d=0.68; 95% CI −1.10 o −0.26), compa ed wi h WL, wi h medium e ec sizes, and no di e ences be ween he wo expe imen al condi ions (mean di e ence 1.09; P=.65; d=0.05; 95% CI −0.39 o 0.49). Finally, pa ien s in he TIBP condi ion expe ienced a la ge inc ease in PA (PANAS-P) compa ed wi h WL (mean di e ence 5.42; P<.001; d=0.74; 95% CI 0.33 o 1.15) wi h mode a e e ec sizes and g ea e educ ions in NA (PANAS-N; mean di e ence −8.34; P<.001; d=0.99; 95% CI −1.41 o −0.57) compa ed wi h WL wi h la ge e ec sizes. Pa icipan s in he TIBP+PA condi ion expe ienced he same pa e n as he pa icipan s in he TIBP condi ion bu achie ing la ge e ec sizes o bo h highe PA (mean di e ence 7.86; P<.001; d=0.90; 95% CI 0.49 o 1.31) and lowe NA (mean di e ence −8.32; P<.001; d=0.91; 95% CI −1.32 o −0.50) han pa icipan s in he WL condi ion. No di e ences we e ound be ween he wo expe imen al condi ions on PA (mean di e ence −2.44; P=.08; d=0.25; 95% CI −0.66 o 0.17) o NA (mean di e ence −0.02; P=.99; d=0.01; 95% CI −0.42 o 0.40). J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 9h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X pa icipan s and adhe ence o he p og am. Indeed, his aspec has g ea ele ance in he li e a u e on in e ne -based in e en ions [95,96]. The e o e, i his ype o in e en ion is ca ied ou on a la ge scale in he communi y, as in his s udy, a undamen al ac o o conside is he ype and amoun o suppo o p o ide, which would be consis en wi h he s udy o he balance be ween he bene i s and esou ces in ol ed in p o iding human suppo in in e ne -based in e en ions. Technologies play a cen al ole in his aspec because pa o he suppo can be p o ided au oma ically h ough echnological de ices. In an a emp o unde s and his issue, ou esea ch g oup conduc ed a quali a i e s udy o de e mine why pa ien s d opped ou o he web-based ansdiagnos ic p og am o EDs (TIBP) [97], wi h he esul s emphasizing he lack o indi idualiza ion o he ea men o he lack o suppo (ie, he lack o a ec i e and pe sonal con ac wi h he he apis ). In his ega d, u u e s udies should de elop pe sonalized ea men s o add ess pa ien s’speci ic needs and inc ease adhe ence a es. The e a e some use ul s a egies o pe sonalizing ea men s, such as selec ing ce ain ea men componen s o be e i he pa ien ’s symp oms o lowe ing he numbe o sessions equi ed o success ully ea an indi idual’s symp oms. One s a egy implies pe sonalizing he ea men o a speci ic p esen a ion, ha is, by selec ing he ea men componen s ha bes i he speci ic se o symp oms o weaknesses shown by each pa ien [10], he eby lowe ing he numbe o sessions equi ed o success ully ea an indi idual’s symp oms. Ano he example is he s udy by Ca l e al [98]. In his s udy, he au ho s p esen ed a module o he egula ion o PA ha can be added o he ea men once hey ha e comple ed he UP modules, hus pe sonalizing he ea men o pa ien s who show de ici s in posi i e emo ions a pos ea men . This s udy has se e al s eng hs. Fi s , i p esen s a no el ocus in he ield o ansdiagnos ic ea men s. To he bes o ou knowledge, his is he i s s udy o a ansdiagnos ic in e ne -based ea men o EDs wi h a speci ic componen o up egula e PA. O e all, he indings indica e ha EDs can be e ec i ely ea ed wi h a ansdiagnos ic in e en ion ia he in e ne , in addi ion o imp o ing dep ession, anxie y, and quali y o li e measu es. Rega ding PA measu es, p omising e ec s we e ound, bu mo e esea ch is needed o s udy he ole o posi i e emo ions in he cons uc ion o psychological s eng hs [99,100] om a ansdiagnos ic pe spec i e [42,101]. Mo eo e , his s udy included a la ge sample o people om a communi y sample, ep esen ing a he e ogeneous popula ion wi h EDs ha does no ecei e p ima y o specialized ca e, wi h o wi hou he p esence o como bidi ies. Thus, he ansdiagnos ic p o ocol ep esen s a success ul app oach o he ea men o mul iple diso de s in a pa simonious manne [102]. Pa icipan s in he s udy seemed o be in e es ed in he use o adap i e emo ion egula ion s a egies, ega dless o whe he hey we e ela ed o hei own di icul y, which is he basis o ansdiagnos ic p oposals. These in e en ions emphasize he essen ial p ocesses unde lying di e en diso de s and he use o co e highe -o de s a egies ha elimina e he need o mul iple diagnosis-speci ic manuals [103]. Mo eo e , he in e ne -based o ma o his ansdiagnos ic p o ocol acili a es he a ailabili y and adminis a ion o he p og am o p o ide suppo o anyone in need. Limi a ions This s udy also has some limi a ions. The mos impo an is he di e en numbe o modules in he wo p o ocols (TIBP condi ion: 12 modules; TIBP+PA condi ion: 16 modules). The TIBP condi ion had mo e ime be ween he las module and pos assessmen han he TIBP+PA condi ion. Howe e , he TIBP+PA condi ion had mo e modules. Pos assessmen ook place a he end o module 12 o 16. These aspec s may ha e in luenced he esul s. In an a emp o con ol his, equal ime (ie, a maximum pe iod o 18 weeks om andomiza ion o pos ea men e alua ion) was gi en o all pa icipan s o allow hem o use he p og am as much as hey desi ed h oughou he whole p ocess. Howe e , u u e s udies should show ha he di e en ial e ec o he PA componen is no simply because o he la ge numbe o modules in he p o ocol. This leads o he impo ance o benchma king based on p e ious ansdiagnos ic in e ne -based in e en ions wi h ega d o e ec sizes o he leng h o hese in e en ions. This s udy coincides wi h p e ious simila ansdiagnos ic in e en ions ha also ob ained la ge e ec sizes o dep ession (g=0.84) and medium e ec sizes o anxie y (g=0.78), wi h a ea men leng h anging om 6 o 10 sessions [18]. Fu he mo e, ocusing on PA measu es, i is impo an o men ion ha his s udy ob ained la ge e ec sizes o PA, bo h o wi hin- and be ween- compa isons (TIBP+PA, d=1.27; TIBP+PA s WL, d=0.90) han o he ansdiagnos ic in e en ions [13,14,50-53]. Ano he limi a ion o he s udy, sha ed wi h o he ansdiagnos ic in e en ions, is ha al hough hey a e called ansdiagnos ic ea men s, hey a e based on disc e e diagnos ic ca ego ies (ie, DSM-IV). Fu u e esea ch should s udy he mechanis ically ansdiagnos ic p inciples, ha is, he unde lying mechanisms ha accoun o he occu ence o speci ic symp oms o include hem in bo h assessmen s and ansdiagnos ic in e en ions. Some examples o ansdiagnos ic mechanisms ha ha e been ound o play a undamen al ole in EDs a e in ole ance o unce ain y [104], umina ion [105], pe ec ionism [106], o hough supp ession [107]. Among hese p ocesses, neu o icism has been s ongly associa ed wi h bo h anxie y and dep essi e diso de s [86,108]. In addi ion, a i ion a es we e highe in bo h ea men condi ions (TIBP: 26/71, 37%; TIBP+PA: 27/73, 37%) han in he WL condi ion (17/72, 24%). Howe e , a i ion a es o 30% o 35% a e commonly obse ed in in e ne -based in e en ions [47]. Fu he mo e, al hough we conside ha he sample o his s udy is qui e ep esen a i e, u u e esea ch should ocus on imp o ing he men al heal h o less eachable g oups such as olde people, people wi h low income o lowe educa ional le el, and/o people esiding ou side u ban a eas (ie, u al popula ions). Mo eo e , i would also be impo an o collec da a on ce ain demog aphic a iables such as ace, e hnici y, and sexual o ien a ion in u u e ials. T ansdiagnos ic ea men s ha a e sociocul u ally adap ed o such g oups could be a po en ial solu ion o e ec i ely each a la ge numbe o people in need o psychological help. Finally, ollow-up da a we e no included in his s udy because we a e s ill in he ec ui ing p ocess, and we wan ed o p omp ly p o ide he esul s because o he impo ance o he issue. The long- e m e ec s o his in e en ion will be p esen ed in u he esea ch. J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 16h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X Conclusions In summa y, he esul s show he e icacy o a ansdiagnos ic in e ne -based psychological ea men p o ocol o indi iduals om a communi y sample wi h EDs. These indings show ha his web-based ansdiagnos ic ea men imp o ed he clinical si ua ion o he pa icipan s, p o iding hem wi h ools and s a egies o ace p oblems and di icul ies mo e e ec i ely. Fu u e lines o esea ch should ca y ou disman ling designs o de e mine he ac i e componen s o he p o ocol, especially he con ibu ion o he PA modules, and analyze he e ec i eness o web-based ea men in o he popula ions, such as p ima y ca e cen e s. Fu he mo e, he exis ing echniques and s a egies o imp o e PA equi e u he s udy o de e mine which ones a e mo e e ec i e and should be included as speci ic componen s o up egula e PA in cu en psychological in e en ions. This s udy includes some speci ic s a egies o p omo e psychological s eng hs and enhance posi i e mood. Howe e , i is impo an o u u e s udies o explo e mo e deeply he e ec o hese and o he s a egies on pa ien s wi h EDs o di ec ly build posi i e esou ces o coun e ac NA. Undoub edly, u u e esea ch will ha e o de e mine whe he i is bene icial o include hese componen s designed o enhance PA, which componen s a e necessa y o whom, and how hey should be applied. Fu he mo e, u u e esea ch should ocus on he possibili y o de eloping ea men componen s aimed a al e ing, modi ying, o a ying ulne abili y, a key aspec o ansdiagnos ic pe spec i es. This migh be possible wi h s a egies o modi ying PA, bu he e a e o he undamen al ac o s ha in luence men al heal h and well-being. Fo example, a la ge body o li e a u e has highligh ed he impo ance o accu a e pe cep ions o eali y in psychological heal h, such as posi i e illusions o posi i e sel -e alua ions, pe cep ions o con ol o mas e y, and un ealis ic op imism [109,110]. In addi ion, he e is e idence o he ela ionship be ween psychological lexibili y and well-being, sugges ing ha being psychologically lexible has bene i s o execu i e unc ioning, de aul men al s a es, and pe sonali y dimensions such as neu o icism [111]. Psychological lexibili y has been conside ed a p o ec i e ac o in imp o ing physical heal h, men al heal h, and well-being [112]. Hence, he e is g owing in e es in cons uc s such as p agma ic p ospec ion, ha is, hinking abou a u u e wi h desi ed ou comes and a oiding undesi ed ones [113] o openness o he u u e cha ac e ized by PA owa d he u u e [114]. This body o knowledge opens up he possibili y o inding new s a egies o imp o e he e iciency and e ec i eness o u u e ansdiagnos ic ea men p o ocols o EDs as a way o mo e e ec i ely add ess empe amen ulne abili ies, ha is, he co e aspec s o hese diso de s. Acknowledgmen s This s udy was unded by he Minis y o Economy and Compe i i eness (Spain; PSI2014-54172-R), a PhD g an om he Minis y o Economy and Compe i i eness (FPI-MINECO; BES-2015-072360), and CIBER Fisiopa ología de la Obesidad y Nu ición-ISCIII CB06/03/0052. Con lic s o In e es None decla ed. Mul imedia Appendix 1 Desc ip ion o he posi i e a ec modules. [DOC File , 38 KB-Mul imedia Appendix 1] Mul imedia Appendix 2 CONSORT-eHEALTH checklis (V 1.6.1). 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[doi: 10.1186/s12955-018-0889-8] Abb e ia ions AG: ago aphobia BA: beha io al ac i a ion BAI: Beck Anxie y In en o y BDI-II: Beck Dep ession In en o y, Second Edi ion BI: beha io al inhibi ion CBT: cogni i e beha io al he apy CONSORT: Consolida ed S anda ds o Repo ing T ials DD: dys hymic diso de DSM-IV: Diagnos ic and S a is ical Manual o Men al Diso de s, Fou h Edi ion E: ex a e sion EBT: e idence-based psychological ea men ED: emo ional diso de GAD: gene alized anxie y diso de ICT: in o ma ion and communica ion echnology ITT: in en ion- o- ea MDD: majo dep essi e diso de MNAR: missing no a andom N: neu o icism NA: nega i e a ec o nega i e a ec i i y NEO FFI: NEO Fi e Fac o In en o y PA: posi i e a ec PANAS: Posi i e and Nega i e A ec Schedule PD: panic diso de RCI: eliable change index RCT: andomized con olled ial SAD: social anxie y diso de TIBP: ansdiagnos ic in e ne -based p o ocol UP: Uni ied P o ocol WL: wai ing lis J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 22h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X Edi ed by T Rashid So on; submi ed 11.06.20; pee - e iewed by L Eus is Ph.D, E Kelly, C Păsă elu; commen s o au ho 23.07.20; e ised e sion ecei ed 10.09.20; accep ed 01.12.20; published 01.02.21 Please ci e as: Díaz-Ga cía A, González-Robles A, Ga cía-Palacios A, Fe nández-Ál a ez J, Cas illa D, B e ón JM, Baños RM, Que o S, Bo ella C Nega i e and Posi i e A ec Regula ion in a T ansdiagnos ic In e ne -Based P o ocol o Emo ional Diso de s: Randomized Con olled T ial J Med In e ne Res 2021;23(2):e21335 URL: h ps://www.jmi .o g/2021/2/e21335 doi: 10.2196/21335 PMID: ©Amanda Díaz-Ga cía, Albe o González-Robles, Azucena Ga cía-Palacios, Ja ie Fe nández-Ál a ez, Diana Cas illa, Juana Ma ía B e ón, Rosa Ma ía Baños, Soledad Que o, C is ina Bo ella. O iginally published in he Jou nal o Medical In e ne Resea ch (h p://www.jmi .o g), 01.02.2021. This is an open-access a icle dis ibu ed unde he e ms o he C ea i e Commons A ibu ion License (h ps://c ea i ecommons.o g/licenses/by/4.0/), which pe mi s un es ic ed use, dis ibu ion, and ep oduc ion in any medium, p o ided he o iginal wo k, i s published in he Jou nal o Medical In e ne Resea ch, is p ope ly ci ed. The comple e bibliog aphic in o ma ion, a link o he o iginal publica ion on h p://www.jmi .o g/, as well as his copy igh and license in o ma ion mus be included. J Med In e ne Res 2021 | ol. 23 | iss. 2 | e21335 | p. 23h ps://www.jmi .o g/2021/2/e21335 (page numbe no o ci a ion pu poses) Díaz-Ga cía e alJOURNAL OF MEDICAL INTERNET RESEARCH XSL • FO Rende X