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Anhedonia, Positive and Negative Affect, andSocial Functioning in Schizophreniaby Jack J . EUtnchard, Kim T. Mueser, and Alan S.BeUack

AbstractThis study examines the relationship between anhedo-nia and the trait dimen sions of positive affect PA) andnegative affect NA) in schizophren ia. The relationshipbetween poor social functioning in schizophrenia andthese individual differences in affectivity is also exam-ined. Schizophrenia outpatients n = 37) and normalcontrols n = 15) were assessed at a baseline evaluationand again approximately 90 days later. Consistent withthe hypothesized decrease in hedonic capacity in schiz-ophrenia, patients reported significantly greater physi-cal and social anhedonia and less PA than controls.However, the schizophrenia group also reportedsignificantly greater NA and social anxiety than did con-trols.In support of the dispositional view of these indi-v i d u a l d i f fe r e n c e s i n a f fe c t i v i ty , t r a i t m e asu r e sdemonstrated test-retest reliability, and group differ-ences between the schizophrenia group and controlswere stable over the 90-day followup period. Withinthe schizophrenia group, physical and social anhedo-nia were comparably negatively correlated with traitPA; however, social but not physical anhedonia wassignificantly positively correlated with NA and socialanxiety. Poor social functioning in the schizophreniagroup was associated with greater physical and socialanhedonia and greater NA and social anxiety. Alter-natively, greater trait PA was related to better socialfunctioning. These findings indicate that schizophreniais characterized by both low PA and elevated NA andthat these affective characteristics are a stable featureof the illness. The results also suggest important linksbetween affect and social functioning in schizophrenia.

Key words: Anhedonia, affect, em otion.Schizophrenia Bulletin 24 3):413-^424,1998.

Anhedonia, the decreased capacity to experience pleasure,has been hypothesized to be a core feature of schizophre-

nia that may contribute to the liability of developing thisdisorder (Meeh l 1962 ; Rado 19 62). Add itionally, bothMeehl and Rado proposed that anhedonia is related toother aspects of emotional functioning in schizophreniaand underlies the social isolation and impairment seen inthis disorder. Although Meehl has since diminished thecentrality of anhedonia in his theory (1990), his originalconjectures inspired a number of studies to examinewhether anhedonia is related to vulnerability to schizo-phrenia (Berenbaum et al. 1990; Katsanis et al. 1990;Clementz et al. 1991; Grove et al. 1991; Chapman et al.1994). In a 10-year followup study of college students,Chapman et al. (1994) found that in association with mag-ical ideation, social (but not physical) anhedonia wasrelated to increased risk for psychosis as well as dimen-sional scores of schizotypal personality at followup. Theyhypothesized that social withdrawal secondary to socialanhedonia may deprive individuals of the benefits ofsocial contact (e.g., emotional support, social validationof cognitions and perceptions), leading to increased riskof psychosis.

Unlike the study of anhedonia as an indicator of psy-chosis proneness, little research has examined how anhe-donia is related to various features of schizophrenia inindividuals with the illness (Chapman et al. 1976; Schucket al. 1984; Berenbaum and Oltmanns 1992; Katsanis etal . 1992; Blanchard et al. 1994). In fact, little is knownabout anhedonia in schizophrenia, including how it isrelated to other domains of affect and social impairmentFurthermore, the temporal stability (i.e., trait status) ofanhedonia has not been directly tested in schizophrenia,only inferred from its relationship with premorbid adjust-ment (e.g., K atsanis et al. 1992).

Despite its definition as a deficit in emotional experi-ence,the aspects of emotion that are affected in anhedon iaReprint requests should be sent to Dr. J .J . Blanchard, Dept. ofPsychology, Logan Hall, University of New Mexico, Albuquerque, NM87131-1161.

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are not w ell understood. To date, research has focused onth e state correlates of anhedonia, and the findings havebeen inconsistent. Berenbaum and Oltmanns (1992) failedto find physical or social anhedonia in schizophreniapatients to be related to self-reported emotional responsesto films and flavored drinks. On the other hand, Blanchardet al. (1994) found that physical, but not social anhedoniais moderately related to decreased self-reported positivemood in response to affect-eliciting films. A similar lackof replication has been found in nonclinical samples: Incollege students , physical anhedonia was unrelated tos e l f - r ep o r t e d m o o d o r f ac i a l d i s p l a y s o f a f f ec t(Berenbaum et a l . 1987) . However , F i tzg ibbons andSimons (1992) found that physically anhedonic collegestudents rated positive and neutral slides as less positivethan normally hedonic subjects. Additionally, Fiorito andSimons (1994) found that college students high in physi-cal anhedonia rated positive images as less positive andboth positive and negative images as less arousing thandid normal controls.Blanchard (Blanchard et al. 1994; Blanchard 1998)has suggested several possible factors to account for thevariability in findings, including the method of moodmeasurement, in particular the affects assessed and theuse of state measures of affect. Another concern with lab-oratory mood induction studies is the nature of the evoca-tive stimuli employed. As observed by Berenbaum et al.(1987), the available data suggest that anhedonia is notrelated to affective responsivity to all forms of stimuli.Actually, Meehl never intended the concept of anhedoniain schizophrenia to be construed as a pan-deficit in thecapaci ty to exper ience p leasure . For example , Meehl(1962) original ly observed that schizoid anhedon ia ismainly interpersonal, i.e., schizotypes seem to derive ade-quate pleasure from esthetic and cognitive rew ards (p.833). Similarly, Meehl (1990), in explaining his prefer-ence for the term hypohedonia, indicated that even themost deteriorated schizophrenia patients can achieve plea-sure from a few sources, such as smoking or watchingtelevision. The inconsistent findings of laboratory moodinduction studies may be a consequence of the failure toexamine social-interpersonal factors, which are presumedto be cen tral to the construct of anhedonia. The neglect ofsocial stimuli in mood manipulation procedures is alsoproblemat ic because socia l - in terpersonal act iv i ty hasrepeatedly been found to be a robust predictor of positiveaffect (Clark and Watson 1988; Wa tson 1988a; Watson etal. 1992; Watson and Clark 1993).

In the present study, we address these concerns byfocusing on the trait affect correlates of anhedonia. Wechose to focus on measuring affect using trait ratings forseveral reasons. First, trait indices of affect should pro-vide more reliable and generalizable markers of affect

than do single-point assessments of mood. Second, inassessing trait affectiviry, we are not constrained by issuesarising from the nature of the evocative stimuli that mightbe used in a mood induction paradigm. A related point isthat trait markers of positive affect h ave been shown to besignificantly associated with social-interpersonal activity(e.g., Watson 1988a; W atson et al. 1992). Third, the use oftrait indices should allow a better understanding of anhe-donia in the context of prevailing models of personalityand affect In particular, how is anhedonia related to thepersonality dimensions of positive affect (PA) and nega-tive affect (NA) (e.g., Zevon and Tellegen 1982; Tellegen1985; Watson and Tellegen 1985; Watson 1988Z>; Watsonand Clark 1992a, 19926; Tellegen and Waller, in press)? Itis important to note that PA and NA are viewed as largelyindependent dimensions that may have differential (notjust opposite) correlations with other variables (e.g., Costaand McCrae 1980; Tel legen 1985; Clark and Watson1988; Watson 1988a; Watson et al. 1992; Tellegen andWaller, in press).The fi rs t object ive of this s tudy was to test thehypothesis that anhedonia, as well as positive and nega-tive affectivity, reflect enduring individual differences inpersons with schizophrenia. Although data from nonpsy-chiatric samples have demonstrated the test-retest reliabil-ity of indices of both anhedonia (Chapman et al. 1982)and trait PA and trait NA (e.g., Tellegen and Waller, inpress), there are no published data supporting similar reli-ability in schizophrenia. Thus, the current study examinesthe test-retest reliability of putative trait indicators ofanhedonia and affect in schizophrenia outpatients overapproximately 90 days. Following an approach employedin personality research involving twins (Lykken et al.1992), this study design also affords the opportunity touse a strategy of averaging trait measures from the twoassessments to obtain more reliable estimates of self-ratedtraits. This averaging of trait indices across assessmentsdecreases error variance attributable to both measurementerror and unsystematic variation in self-descriptions ofpersonality (Lykken et al. 1992).

The second aim of this study was to evaluate the rela-tionship between anhedonia and trait dimensions of PAand NA. We hypothesized that anhedonia, as a constructreflecting the decreased capacity to experience pleasure,should be associated with decreased trait PA. The hypoth-esized relationship between anhedonia and trait NA wasless clear. On one hand, the Chapman scales of anhedoniawere developed to be independent of negative affectivestates such as social anxiety (Mishlove and Chapman1985). Personality models that posit independent dimen-sions ofPAand NA would also lead to a prediction of theindependence of anhedonia and trait NA. In support ofthis view, Berenbaum and Connelly (1993) found the

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effect of stress on positive mood and current hedoniccapacity to be independent of its influence on negativemood in college students. Alternatively, Meehl, in bothhis original (1962) and revised (1990) theories, proposedthat anhedonia is an important contributor to or in somecases a consequ ence of what he describes as aversivedrift in schizophren iathe tenden cy for activities, peo -ple, and places to take on a burden som e, threatening,gloomy, negative emotional charge (Meehl 1990, p. 21).This aversive drift is proposed to be intense and pervasivein the interpersonal domain, manifesting as ambivalenceand interpersonal fear (Meehl 1962). Such a proposalw ould i nd i c a t e t ha t a nhe don ia i s c ha r a c t e r i z e d bydecreased PA and increased NA. Therefore, we sought totest the hypothesis that anhedonia is related to low traitPA as well as elevated trait NA .

The third aim of this study was to assess the relation-ship between anhedonia and social functioning in schizo-phrenia. Social dysfunction is a central feature of schizo-phrenia, as reflected by the inclusion of social dysfunctionin the diagnostic criteria for the active phase of schizo-phrenia and as a symptom of the prodromal and residualphases of the illness (American Psychiatric Association1987, 1994), as well as repeated demonstration of socialimpairment in this disorder (e.g., Bellack et al. 1990;Mueser et al. 1990). Anhedonia has been hypothesized tounderlie the social withdrawal and impairment seen inschizophrenia (Meehl 1962). In support of Meehl's con-jectures, anhedonia in schizophrenia subjects has beenf ound to be r e l a t e d t o poor p r e m or b id a d jus tm e nt(Chapman et al. 1976; Schuck et al. 1984; Katsanis et al.1992). Similarly, in studies of college students, high anhe-donia is related to various indices of decreased socialcompetence (Haberman et al. 1979; Chapman et al. 1980;Numbers and Chapman 1982; Beckfield 1985; Mishloveand Chapman 1985). However, in a recent study of inpa-tients with schizophrenia, Blanchard et al. (1994) reportedthat anhedonia is not related to behavioral rat ings ofsocial skill, at least in conflictual negative encounters.Blanchard (1998) suggested the need to explore howanhedonia is related to other dimensions of social func-tionin g, includ ing soc ial skill in affUiative social-interpe r-sonal encounters and current social functioning in thecommunity.To determine how anhedo nia relates to the socialactivities of patients in the community, we examined therelationship between anhedonia and current social func-tioning in a sample of stabilized schizophrenia outpa-tients. We hypothesized that anhedonia would be relatedto poorer social functioning (e.g., fewer friends, lessromantic involvement, fewer social-interpersonal activi-ties). Related to this, we sought to replicate in schizophre-nia subjects the findings from nonpsychiatric populations

that trait markers of PA, but not NA , are positively relatedto socia l- interp erson al activity (e.g. , Watson 1988a;Hotard et al. 1989; Watson et al. 1992; Watson and Clark1993). Therefore, we predicted that trait PA, but not traitNA, would be assoc ia ted wi th soc ia l adjus tment inschizophrenia subjects and that greater trait PA would berelated to better social adjustment.In summary, schizophrenia outpatients and normalcontrols were assessed twice in approximately 90 days totest the following hypotheses: (1) trait indices of anhedo-nia and affectivity are temporally stable in both schizo-phrenia subjects and controls; (2) schizophrenia subjectsreport greater anhedonia than controls, and anhedonia isassociated w ith less trait PA and greater trait NA; an d (3)schizophrenia subjects demonstrate poorer social func-tioning than controls, and this poor social functioningwould be correlated with greater anhedonia and less traitPA; however, it was predicted that social functioning isnot associated with trait NA.MethodsOverview. The study involved a baseline evaluation anda followup assessment. Although efforts were made toconduct followup assessments at 90 days, time betweenassessments varied as a function of subject schedules andavailability. The schizophrenia and control groups did notdiffer in their average time between assessments t =- 1 . 5 9 , df = 50, NS; schizophrenia group, mean daysbetween assessments = 96.54, standard deviation [SD] =14.10, minimum = 77, maximum =147; control group,mean days between assessments = 90 .13, SD = 10.24,minimum = 72, maximum = 112). At baseline, diagnosticevaluations were conducted with the Structured ClinicalInterview for DSM-II1-R patient and nonpatient editions(SCID; Spitzer et al. 1990) to determine study inclusioncriteria. Videotaped clinical interviews were conducted atboth assessments to evaluate social functioning in schizo-phrenia subjects and controls and to record symptomatol-ogy in the schizophrenia subjects during the month pre-ceding the interview. Data regarding symptomatologyra ted on the Br ie f Psychia t r ic Rat ing Sca le (BPRS;Overall and Gorham 1962) are presented in a separatereport (Blanchard and Bellack, submitted for publication).Following the clinical interview, subjects were accompa-nied by a research assistant to a separate room and wereinstructed in completing self-report scales. Self-reportmeasures included indices of physical and social anhedo-nia, trait PA and trait NA, and social anxiety. Measures ofanxiety were included in the present study because ofMeehl's (1962) proposal that aversive drift is character-ized in part by exaggerated interpersonal fear. Items from

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the true-false anhedonia and trait affectdvity scales wereintermixed and combined to form one self-report inven-tory. The social anxiety scales were administered sepa-rately because of their different response format. Clinicalinterviewers were blind to all self-report scores at bothassessments.Subjects. Participan ts included 43 schizophrenia outpa-tients and 15 control subjects. Participants were paid fortheir involvement in the study. Schizophrenia subjects,who consented to participate and met the diagnostic crite-ria of DSM-HI-R (American Psychiat r ic Associa t ion1987), were drawn from the outpat ient SchizophreniaClinic at the Medical College of Pennsylvania/EasternPennsylvania Psychiat r ic Ins t i tu te . Cont ro l s were re-cruited from the Medical College of Pennsylvania's cleri-cal and support staff and screened for psychiatric disor-d e r s . D i a g n o s t i c i n f o r m a t i o n o n a l l p a r t i c i p a n t s(schizophrenia and control) was obtained using the moodsyndromes and psychotic and associated symptoms sec-tions of the SCDD (Spitzer et al. 1990). Diagnostic inter-views were conducted by a Master's- or Ph.D.-level diag-nostic interviewer with extensive training and experiencein diagnostic and symptom assessment from involvementin earlier studies, including the Treatment Strategies inSchizophrenia study of the National Institute of MentalHealth (Keith et al. 1989, Schooler et al. 1989), and for-mal training in the use of the SCID. Prior training fromthe Spitzer group in the SCTD established high diagnosticagreement between the raters for the diagnoses studied(kappas > 0.90). Six schizophrenia subjects were droppedfrom the study because they refused to participate in fol-lowup assessments (2) or because project s taff wereunable to locate them at followup (4). Patients who werenot available for the followup did not differ from thoseassessed at both followups in any demographic or treat-ment-history variables, nor did they differ on any of theself-report scales or in rat ings of social funct ioningobtained at the initial evaluation. The final schizophreniasample had 37 patients who w ere available for assessmentat both baseline and followup.

This stabilized schizophrenia outpatient sample had amean of 4.33 prior hospitalizations (SD = 3.00), and theaverage number of months since the last hospitalizationwas 21.73 (SD = 33.21). All schizophrenia subjects weremedicated and their average dose of neurolept ics , inchlorpromazine uni t equivalen ts (American MedicalAssociation 1994, p. 263), was 770 m g (SD = 406). Fourpatients were receiving neuroleptics for which chlorpro-mazine equivalence i s no t avai lab le : remoxipr ide (3patients; mean dose =150 mg, SD = 75) and risperidone(1 patient; 16 mg). Nineteen patients were on anti-Parkin-sonian medication (benztropine equivalents: mean = 2.13

mg, SD =1.33); four patients were also taking a benzodi-azepine (lorazepam: mean = 2.50 mg, SD = 1.73); an done patient was receiving lithium (1,200 mg) in additionto a neu roleptic.Schizophrenia subjects did not differ from controls inage (f = -0.11, df = 50, NS; schizophrenia patient mean

age = 36.14, SD = 7.46; control 36.40, SD = 9.69), educa-tion (/ = -0.57, df = 50, NS; schizophrenia patient meanyears of education = 12.27, SD = 2.05; control 12.60,SD = 1.45), or race (X2[l , n =52] = 0.02, NS). Most ofthe sample was African -Am erican (24 schizoph reniapat ients , 10 controls; the remaining part icipants wereCaucasian (13 schizophrenia patients, 5 controls). Therewere no group differences in gender (X 2[l ,n= 52] = 1.87,NS), although a somewhat larger percentage of schizo-phrenia subjects were male (73%,n = 27) compared withcontrols(53%,n= 8).Instruments.A n h e d on i a . Anh edonia was assessed wi th therevised versions of the Physical Anhedonia Scale (Chap-man and Chapman 1978) and the Social Anhedonia Scale(Eckblad et al. 1982). These true-false self-report mea-sures provide indices of the pleasure derived from physi-cal and social-interpersonal sources, respectively. Theyhave been shown to be reliable, with internal consistencyreliabilities (coefficient a) of 0.79 to 0.82 for the PhysicalAnhedonia Scale (Chapman et al. 1982) and 0.79 for theSocia l Anhedonia Scale ( repor ted in Mishlove andChapman 1985). Six-week test-retest reliability for thePhysical Anhedonia Scale in normal college students hasbeen found to be adequate r> 0.77). Test-retest reliabilityfor the Social Anhedonia Scale has not been reported.

Trait measures of affect Trait indic es of affectiv-ity were derived from the Multidimensional PersonalityQuestionnaire (MPQ; Tellegen 1978/1982, 1985; Tellegenand Waller, in press), a true-false self-report questionnaireto measure normal personality characteristics, which hasbeen used in several studies of psychopathology (e.g.,DiLalla et al. 1993; Berenbaum et al. 1994; DiLalla andGottesman 1995). Trait PA was assessed with the Well-Being scale and trait NA with the Stress Reaction scale ofthe MPQ. As in other studies employing these scales (e.g.,Watson et al. 1988; Church and Burke 1994), our reportedresults are based on the abbreviated versions (11 items forWeil-Being and 14 items for Stress Reaction) becausethey are less correlated with each other than the fullscales. The Well-Being scale measures the tendency toexper ience pos i t ive emot ions : High scorers descr ibethemselves as happy, enthusiastic, optimistic, and experi-encing enjoyment from activities; low scorers experiencelittle joy and are seldom happy. This PA trait marker ispositively correlated with state indices of PA (Tellegen

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1985;Watson 1988a), social activity (Watson 1988a), andthe quantity and quality of social relationships (Hotard etal . 1989). The Well-Being scale has been found internallyconsistent (coefficient a > 0.85) and temporally stable(30-day test-retest r =0.90) (Tellegen 1978/198 2, 1985 ;Tellegen and W aller, in press).

The Stress Reaction scale of the MPQ was used fortrait NA because it reflects the tendency to experiencenegative affect. High scorers on the Stress Reaction scaledescribe themselves as anxious, worrying, and irritable;low scorers convey a higher threshold for experiencingNA and greater coping with stress. The Stress Reactionscale is positively correlated with state indices of NA(Tellegen 1985; Watson 1988a; Tellegen and Waller, inpress) and heal th complaints (Watson 1988a) and hasbeen found to be internally consistent (a > 0.88) and tem-poral ly s table (30-day test-retest r = 0.89) (Tel legen1978/1982; Tellegen and Waller, in press).Social anxiety. Social anxiety was mea sured withthe Interaction Anxiousness Scale (Leary 1983b) and thebrief Fear of Negative Evaluat ion Scale (Watson andFriend 1969; Leary 1 983a ).1 The Interaction AnxiousnessScale is a 15-item scale that measures the subjective expe-

rience of anxiety associated with social interactions. Eachitem is scored on a scale of 1 (not at all characteristic ofme) to 5 (very characteris t ic of me). The Interact ionAnxiousness Scale has good internal consistency (Leary1983b), is significantly correlated with other self-reportmeasures of social anxiety (Leary 19836; Herbert et al.1991; Leary and Kowalski 1993), and discriminates indi-viduals with interpersonal difficulties involving anxietyfrom nonclinical controls (Leary 19836). The brief ver-sion of the Fear of Negative Evaluat ion Scale (Leary1983a) measures anxious apprehension related to theprospect of being evaluated negat ively by others . Thebrief Fear of Negative Evaluation Scale is a 12-item ques-tionnaire that uses a 5-point scale with anchors similar tothose used for the Interaction Anxiousness Scale. It hasgood internal consistency (Leary 1983a) and is signifi-cantly associated with other self-report measures of socialanxiety and avoidance (Leary 1983a; Herbert et al. 1991),including the In teract ion Anxiousness Scale (Leary1983a, 19836).

Social functioning. Sub jects' ability to function inthe community during the month before each assessmentwas evaluated with an abbreviated Social AdjustmentScale-I I (SAS-II ; Schooler e t a l . 1979) . The Socia lAdjustment Scale is a widely used interview measure ofcommunity functioning developed specifically for use'One control subject did not complete the Fear of Negative EvaluationScale at the baseline assessment and another control subject did notcomplete the Interaction Anxiousness Scale at the followup evaluation.Both were dropped from analyses involving these measures.

with schizophrenia patients. The SAS-II has establishedreliability, and protocols based on patient interviews haveshown a high correspondence to data provided by com-munity informants (Glazer et al. 1980); patient interviewshave been shown to be related to behavioral indices ofsocial competence (Mueser et al. 1990). Nine items fromSocial Leisure, Interpersonal Contacts, and Romantic In-volvemen t sections of the Social Adjustment Scale wereused. Each item is scored on a 5-point scale with higherscores reflecting poorer functioning. The nine items weresummed and used to form an index of current social func-t ioning. In the present sample, the Social AdjustmentScale index of social functioning had high internal con-sistency at both baseline (a = 0.88) and followup (a =0.85). Interrater agreement for this rating of social func-tioning, calculated on 20 percent of the interviews, washigh, with an Intraclass Correlation Coefficient (ICC) of0.99 (ICC form 2, 1; Shrout and Fleiss 1979).

Items in the SAS reflect both frequency of socialactivities (i.e., type a nd frequency of social-leisure activi-ties engaged in, frequency of social contacts, degree ofparticipation in these social contacts, frequency of seeingor being in contact with friends by phone or letter, andfrequency of romantic contacts) and satisfaction or com-fort with these activities (i.e., comfort while being withother people, ease of communication with friends, degreeof friction with friends, and sensitivity to any difficultieswith friends). Given the intent of the present study toexamine group differences and correlates of social behav-ior rather than satisfaction or comfort with such behavior,substantive analyses in this report will focus on an indexof social frequency based on the five items of the SAStapping this domain. These items were summed and usedto form an index of social adjustment defined by fre-quency of social contacts. Internal consistency remainedadequate with this abbreviated scale (baseline a = 0.84;followup a = 0.77).

ResultsFirst, analyses were conducted to examine the internalconsistency and test-retest reliability of the self-reportmeasures in both subject groups. Second, differencesbetween schizophrenia and control groups in anhedonia,affectivity, social anxiety, and social functioning at bothassessments were evaluated. Finally, correlational analy-ses were conducted to assess the relationships betweenanhedonia, affectivity, anxiety, and social functioningwithin the schizophrenia group.Reliability. Internal consistenc y reliability (coefficienta) was examined for each of the self-report scales. For thePhysical and Social Anhedonia scales, median a = 0.86

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and 0.84, respect ively ac ross assessmen ts and groups .Adequate reliabilitywasalso obtainedfor theWell-Beingand Stress React ion scales, with median a = 0.76 and0.85, respect ively. Similarly, internal consistency wasgoodfor theInteraction Anxiousness Scale,0.89, and theFearofNegative Evaluations Scale,0.82.

Test-retest reliabilityof the self-report scalesof affectand interview-rated social adjustment in schizophreniaand control groups was examined with Pearson product-moment corre la t ions .As can be seen in table 1, self-descriptions of affect in both schizophrenia subjectsandcontrols were reliable across the 90-day followup withstability coefficients of0.74orgreater. One exceptionwas

Table 1. Test-retest reliabilitiesofanhedoniaaffect anxiety andsocial adjustmen t scalesinschizophrenia and control group sInstrumentPhysical Anhedon ia S caleSocial Anhedon ia S caleWell-BeingStress ReactionInteraction Anxiousness Scale

GroupSchizophrenia

0.740.790.750.770.77Fearof Negative Evaluation Scale 0.60Social Adjustment ScaleIIabbreviated 0.66

Control0.860.820.790.790.900.910.50 1

Note Becauseof missing datafor theInteraction Anxiousness(Leary 1983b)andFearof Negative Evaluation (Leary 1983a)scales, control group n- 14.p< 0.001 (one-tailed) exceptas indi-cated.Physical Anhedonia Scale (Chapman and Chapman 1978);Social Anhedonia Scale (Eckbladeta l. 1982); Well-BeingandStress React ion of the Mu l t id imensional Personal ityQuestionnaire (Tellegen 1 978/1982); Soda) Adjustment ScaleIIabbreviated (Schoolere tal.1979).1p


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For the anxiety measures, the ANOVAs resulted in asignificant main effect of Group for the Interact ionAnxiety Scale (F = 12.14; df= 1,49; p


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puted using the Weil-Being and Stress Reaction scales.2After controlling for Well-Being, the correlation betweenSocial Adjustment and Stress Reaction was not significant pr =0.17 , NS). Howe ver, after controlling for S tressReaction, the partial correlation between Well-Being andSocial Adjustment remained significant pr =-0 . 4 6 ,p

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ANHEDONIA EQZ