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VOL. 13, NO. 2,1967 The Positive and NegativeSyndrome Scale
(PANSS)for Schizophrenia
by Stanley R. Kay, AbrahamFlszbeln, and Lewis A. QpJer
Abstract
The variable results of positive-negative research with
schizo-phrenics underscore the importanceof well-characterized,
standardizedmeasurement techniques. We reporton the development and
initialstandardization of the Positive andNegative Syndrome Scale
(PANSS)for typological and dimensional as-sessment. Based on two
establishedpsychiatric rating systems, the 30-item PANSS was
conceived as anoperationalized, drug-sensitive in-strument that
provides balancedrepresentation of positive and nega-tive symptoms
and gauges their re-lationship to one another and toglobal
psychopathology. It thusconstitutes four scales measuringpositive
and negative syndromes,their differential, and general sever-ity of
illness. Study of 101 schizo-phrenics found the four scales to
benormally distributed and supportedtheir reliability and
stability. Posi-tive and negative scores were in-versely correlated
once theircommon association with generalpsychopathology was
extracted,suggesting that they represent mu-tually exclusive
constructs. Reviewof five studies involving thePANSS provided
evidence of its cri-terion-related validity with anteced-ent,
genealogical, and concurrentmeasures, its predictive validity,
itsdrug sensitivity, and its utility forboth typological and
dimensionalassessment.
Schizophrenia has long been re-garded as a heterogeneous
entity,and over the decades researchershave sought consistent
subpattemsthat might explain different aspectsof this complex
disorder. Most re-cently, Crow (1980a, 1980b) and An-dreasen (1982;
Andreasen and Olsen1982) have proposed that two dis-
tinct syndromes in schizophreniacan be discerned from the
phe-nomenological profiles. The Type I,or positive, syndrome is
composedof florid symptoms, such as delu-sions, hallucinations, and
disor-ganized thinking, which aresuperimposed on the mental
status.The Type II, or negative, syndromeis characterized by
deficits in cogni-tive, affective, and social functions,including
blunting of affect and pas-sive withdrawal.
It has been speculated that thesesyndromes in schizophrenia
bearetiological, pharmacological, andprognostic import. Thus,
Crow(1980a) conceived of the positivesymptoms as an aspect of
hyper-dopaminergia (hence, a neuroleptic-responsive disorder) in
contrast to astructural brain deficit that wasthought to underlie
the negativesymptoms. The research to date hasprovided some
indirect support forthis model (e.g., Johnstone et al.1976, 1978a,
19786; Andreasen andOlsen 1982), but the diversity of re-sults has
defied clear-cut interpreta-tions. For example, Angrist,Rotrosen,
and Gershon (1980) notedthat one of the three negative symp-toms
assessed improved with neu-roleptics, and Andreasen et al.(1982)
found none of five negativesymptoms to be associated
withventricular size as assessed by com-puted tomography of
schizophrenicpatients. The distinctiveness of thesyndromes and
their stability overdifferent phases of illness also havebeen
questioned. Whereas An-dreasen and Olsen (1982) contendedthat
positive and negative syn-dromes are "at opposite ends of
acontinuum," Pogue-Geile and Har-
Reprint requests should be sent to Dr.Stanley R. Kay, Research
and Assess-ment Unit, Bronx Psychiatric Center,1500 Waters PI.,
Bronx, NY 10461.
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262 SCHIZOPHRENIA BULLETIN
row (1984) observed a significantinterrelationship during
theposthospitalization phase. Linden-mayer, Kay, and Friedman
(1986)further demonstrated that the exter-nal correlates of
positive and nega-tive syndromes among acuteschizophrenics change
over thecourse of 2 years.
Research findings, of course, areat best only as reliable and
valid asthe measures on which they arebased. Thus, a fundamental
sourceof variability that can account for thedisparate results is
the instrumentused for positive-negative assess-ment.
Well-characterized and stand-ardized techniques are a
clearprerequisite for meaningful study ofthese syndromes, their
relationshipto other features of schizophrenia,and their response
to medication.Although several carefully con-ceived scales have
been devised re-cently (e.g., Andreasen and Olsen1982; Lewine,
Fogg, and Meltzer1983; Heinrichs, Hanlon, and Car-penter 1984;
lager, Kirch, and Wyatt1985), none have undergone thethorough
process of psychometricstandardization that is necessary toaddress
fundamental, and as yethighly contested, issues of contentand
construct validity (Sommers1985). It has also been a matter
ofconcern that to achieve satisfactoryreliability and validity,
more rigor isneeded in providing strict opera-tional criteria for
eliciting, defining,and measuring symptoms (Zubin1985). Other
limitations in some ofthe reported methods include thefollowing:
(1) evaluation of the pres-ence but not severity of
componentsymptoms, (2) imbalance in thenumber of items representing
posi-tive and negative facets, (3) inap-plicability for both
typological anddimensional assessment of syn-dromes, (4) no
evidence of sen-sitivity for monitoring drug-related
changes, (5) no measurement of therelative preponderance of
positiveversus negative symptoms, and (6)no measure of general
psycho-pathology and its possible influenceon the severity of
positive and nega-tive syndromes.
The purpose of this study was todevelop and standardize a
well-de-fined instrument for positive-nega-tive assessment that
attends to thesemethodological and psychometricconsiderations. In
addition, we rec-ognized the need for a procedurethat can be
applied in relatively brieftime (40-50 minutes), with
minimalretraining and reorientation for theclinician, and that can
be used re-peatedly for longitudinal or psycho-pharmacological
assessment. We re-port here on the development andinitial
standardization of the Positiveand Negative Syndrome Scale(PANSS)
involving 101 schizo-phrenics and review evidence of itsvalidity
from five separate studies.
MethodsSubjects and Design. Patients withan unqualified
diagnosis of schizo-phrenia were surveyed to assess
thedistribution, reliability, construct va-lidity, and
criterion-related validityof the PANSS. The medical charts
ofinpatients from long-term psychi-atric units in a
university-affiliatedurban hospital were screened con-secutively to
select those having aformal DSM-III diagnosis of schizo-phrenia
(American Psychiatric Asso-ciation 1980). All cases
withquestionable diagnosis, knownorganic disorder, or mental
retarda-tion were excluded. The remainderwere interviewed on their
ownwards by one of two research psy-chiatrists to ascertain
independentlywhether patients met DSM-11I crite-ria for
schizophrenia. If diagnoseswere thus confirmed, patients un-derwent
the semiformalized PANSS
interview (infra) and were then as-sessed on the PANSS scales
plus aseries of measures deriving fromclinical interview, cognitive
testing,motor assessment, and careful re-view of medical and
historical rec-ords. These measures are describedin separate
articles that chiefly ad-dress their relationship to positiveand
negative syndromes (Kay,Opler, and Fiszbein 1986; Opler,Kay, and
Fiszbein 1986).
The assessments were conductedby two research psychiatrists, one
ofwhom collected data on 47 patientsand the other on 54. Both
psychia-trists first underwent intensive train-ing in the PANSS
interview andrating methods until satisfactoryteam concordance was
achieved,and subsequently they rated pa-tients individually. The
raters heldno a priori assumptions about theoutcome of data and
were unawareof results on the PANSS, which wasundertaken before
other measuresbut scored only after the conclusionof study.
The final sample consisted of 101subjects of ages 20-68 (mean
=36.81, SD = 11.16), including 70males, 31 females, 33 whites,
43blacks, and 25 Hispanics. Twelvepatients were married, 10
divorced,and the remainder single. Meaneducation was 10.09 years
(SD =2.92), with the range extending to 4years of college in four
cases.Twenty-nine subjects had a first-de-gree relative who was
previouslyhospitalized for psychiatric treat-ment; schizophrenia
was specifiedin five cases and affective disorder(depressive,
manic, or bipolar) in 10cases; alcohol abuse was reported inthe
nuclear family of 16 patients;and among 13 subjects there was
ev-idence of family sociopathy, asjudged by record of criminal
be-havior and prosecution.
On the average, patients were
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VOL 13, NO. 2,1987 263
first hospitalized at age 22.39 years(SD = 8.63) and had since
been illfor 14.41 years (SD = 8.95), with amedian of six separate
admissions.Over the past year and a half, 67.4percent of the sample
experiencedcontinuous hospitalization, while forthe remainder the
mean duration ofinpatient stay was 195 days. Allwere receiving
neuroleptic medica-tion in standard dose ranges at thetime of
study.
Assessment Procedure. The PANSSratings are based on all
informationpertaining to a specified period,usually the previous
week. The in-formation derives from both clinicalinterview and
reports of primarycare staff (if institutionalized) orfamily
members. The latter is the es-sential source for assessing
socialimpairment, including items of im-pulse control, hostility,
passivewithdrawal, and active social avoid-ance. All other ratings
accrue from a30- to 40-minute semiformalizedpsychiatric interview
that permitsdirect observation of affective, mo-tor, cognitive,
perceptual, atten-tional, integrative, and interactivefunctions.
The interview may beconceptualized as involving fourphases.1
In the first 10-15 minutes, patientsare encouraged to discuss
their his-tory, circumstances surroundingtheir hospitalization,
their currentlife situation, and their symptoms.The object of this
phase is to estab-lish rapport and allow the patient toexpress
areas of concern. Therefore,the interviewer at this point as-sumes
a nondirective, unchallenging
Full text of the PANSS Rating Man-ual, which includes the
interview proce-dure, item definitions, anchoring
pointdescriptions, and rating form, is avail-able on request from
the authors.
posture to observe, as unobtrusivelyas possible, the nature of
thoughtprocesses and content, judgmentand insight, communication
andrapport, and affective and motor re-sponses.
Deviant material from the firstsegment of the interview is
probedduring the second phase, lasting an-other 10-15 minutes,
through pro-totypic leading questions thatprogress from
unprovocative, non-specific inquiry (e.g., How do youcompare to the
average person? Areyou special in some ways?) to moredirect probe
of pathological themes(e.g., Do you have special or un-usual
powers? Do you consideryourself famous? Are you on a spe-cial
mission from God?). The objectnow is to assess productive symp-toms
that can be judged from thepatient's report and
elaborationsthereof, such as hallucinations, de-lusional ideation,
suspiciousness,and grandiosity. For this purpose,the interviewer
attempts to establishfirst the presence of symptoms andnext their
severity, which is gener-ally weighted according to theprominence
of abnormal manifesta-tions, their frequency of occurrence,and
their disruptive impact on dailyfunctioning.
The third and most focused phaseof the interview, requiring
another5-10 minutes, involves a series ofspecific questions to
secure informa-tion on mood state, anxiety, orienta-tion to three
spheres, and abstractreasoning ability. The evaluation ofabstract
reasoning, for example,consists of a range of questions onconcept
formulation (e.g., How area train and bus alike?) and
proverbinterpretation, which are varied incontent when using the
PANSS forrepeated assessment.
After all the essential rating infor-mation is obtained, the
final 5-10minutes of the interview are allo-
cated for more directive and forcefulprobing of areas where the
patientappeared defensive, ambivalent, oruncooperative. For
example, a pa-tient who avoided forthright ac-knowledgment of
having apsychiatric disorder may be chal-lenged for a decisive
statement. Inthis last phase, therefore, the patientis subjected to
greater stress andtesting of limits, which may be nec-essary to
proceed beyond the socialdemand characteristics inherent inthe
interview situation and to ex-plore susceptibility to
disorganiza-tion.
The interview procedure therebylends itself to observation of
physi-cal manifestations (e.g., tension,mannerisms and posturing,
excite-ment, and blunting of affect), inter-personal behavior
(e.g., poorrapport, uncooperativeness, hos-tility, and impaired
attention), cog-nitive-verbal processes (e.g.,conceptual
disorganization, stereo-typed thinking, and lack of spon-taneity
and flow of conversation),thought content (e.g.,
grandiosity,somatic concern, guilt feelings, anddelusions), and
response to struc-tured questioning (e.g., disorienta-tion,
anxiety, depression, anddifficulty in abstract thinking).Positive
and Negative SyndromeScale (PANSS). Data elicited by thisassessment
procedure are applied tothe PANSS, a 30-item, 7-point
ratinginstrument that has adapted 18items from the Brief
Psychiatric Rat-ing Scale (BPRS) (Overall andGorham 1962) and 12
items from thePsychopathology Rating Schedule(PRS) (Singh and Kay
1975a). Eachitem on the PANSS is accompaniedby a complete
definition as well asdetailed anchoring criteria for allseven
rating points, which representincreasing levels of
psychopathol-ogy: 1 = absent, 2 = minimal, 3 =mild, 4 = moderate, 5
= moderate-
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284 SCHIZOPHRENIA BULLETIN
severe, 6 = severe, and 7 = ex-treme. Four sample items from
thePANSS appear in the Appendix,and scoring is performed on a
sepa-rate rating form in consultation withthe Rating Manual.
In assigning ratings, one first re-fers to the item definition
to deter-mine presence of a symptom. Theseverity of an item, if
present, isthen judged by using a holistic per-spective in deciding
which anchor-ing point best characterizes thepatient's functioning,
whether ornot all elements of the descriptionare observed. The
highest applicablerating point is always assigned,even if the
patient meets criteria forlower ratings as well.
Of the 30 psychiatric parametersassessed on the PANSS, seven
werechosen a priori to constitute a Posi-tive Scale, seven a
Negative Scale,and the remaining 16 a General Psy-chopathology
Scale (see table 3 forthe listing of component items).
The selection of items was guidedby five considerations, in the
follow-ing order of importance: (1) Itemsmust be consistent with
the hypo-thetical construct, i.e., with the the-oretical concept of
positive andnegative psychopathology as repre-senting productive
features super-added to the mental status vs.deficit features
characterized by lossof functioning (cf. Andreasen andOlsen 1982).
(2) As per Carpenter,Heinrichs, and Alphs (1985), itemsshould
comprise symptoms whoseclassification as positive or negativeis
unambiguous and which, by mostaccounts, are regarded as
primaryrather than derivative (as, for exam-ple, impaired
attention, disorienta-tion, and preoccupation may besecondary to
arousal disorder or hal-lucinations). (3) They should be
rep-resentative of different spheres offunctioning (e.g.,
cognitive, affec-tive, social, and communicative) to
optimize content validity. (4) To theextent possible, they
should includesymptoms consensually regarded ascrucial to the
definition of the posi-tive syndrome (e.g.,
hallucinations,delusions, and disorganized think-ing) and negative
syndrome (e.g.,blunted affect, emotional with-drawal, and apathetic
social with-drawal). (5) For practical andpsychometric reasons,
such as facili-tating cross-comparisons and equal-izing reliability
potential, thenumbers of items included in thepositive and negative
scales shouldbe the same.
Insofar as this approach was de-termined by theoretical and
heuristicconsiderations, there was no cer-tainty that all chosen
items would beequally well suited or that all suita-ble items had
been chosen; the inter-nal validity of the scales' composi-tion was
to be determined em-pirically by the data herein assem-bled.
The General PsychopathologyScale was included as an
importantadjunct to the positive-negative as-sessment since it
provides a separatebut parallel measure of severity ofschizophrenic
illness that can serveas a point of reference, or controlmeasure,
for interpreting the syn-dromal scores. It was not assumed
that this scale is statistically or con-ceptually distinct from
the positive-negative assessment (an issue whichalso was to be
determined by thisstudy), but only that it may be usedas a
yardstick of collective non-specific symptoms against which tojudge
severity of distinct positiveand negative manifestations.
In addition to these three scales, abipolar Composite Scale was
con-ceived to express the direction andmagnitude of difference
betweenpositive and negative syndromes.This score was considered to
reflectthe degree of predominance of onesyndrome over the other,
and itsvalence (positive or negative) mayserve for typological
characteriza-tion.
The PANSS is scored by summa-tion of ratings across items,
suchthat the potential ranges are 7-49 forthe Positive and Negative
Scales and16-112 for the General Psycho-pathology Scale. The
CompositeScale is arrived at by subtracting thenegative from
positive score, thusyielding a bipolar index that rangesfrom -42 to
+42.
ResultsDistribution of Scores. Table 1 sum-marizes the
distribution characteris-tics of the four scales from the
Table 1. Distribution characteristics of the PANSS for
101schizophrenics
Distributioncharacteristics
MeanMedianSDRange (potential)
Range (obtained)SkewnessKurtosis
Positive18.20186.087 to 49
7 to 32.07
- .97
Negative21.01206.177 to 49
8 to 38.48.06
PANSS scale
Composite- 2.69- 2
7.45- 4 2 to +42
- 2 5 to +13- .45
.13
Generalpsychopathology
37.7436
9.4916to11219 to 63
.23- .30
NotBPANSS = Positive and Negative Syndrome Scale.
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VOL. 13, NO. 2,1987 265
Figure 1. Frequency polygraph of distributions on the 4 scales
ofthe Positive and Negative Syndrome Scale (PANSS)
401-
30 ->ozLJJ
oaiOCu. 10 -
20 -
-
ir i .
COMPOSITEPOSITIVENEGATIVEGENERAL PSYCHOPATHOLOGY
AJr\ -K../-; ,^x"x-,....
-25 -17 - 9 -1 15 23 31PANSS SCORE
39 47 55 63
PANSS was examined using coeffi-cient a to analyze its internal
consis-tency and the contribution of thecomponent items. As
detailed intable 3, each of the items making upthe Positive and
Negative Scales cor-related very strongly with the scaletotal (p
< .001), and the mean item-total correlations of .62 and .70,
re-spectively, far exceeded the cross-correlations of .17 (Positive
itemswith Negative Scale) and .18 (Nega-tive items with Positive
Scale). The acoefficients with single items re-moved ranged from
.64 to .84, andno perceptible gain on either scale
PANSS, and the full spectrum ofscores is illustrated in figure
1. Allfour measures exhibited a roughlynormal distribution pattern,
withoutsubstantial skewness or kurtosis.This observation suggested
that theconstructs in question represent typ-ical continua and that
their measure-ment is amenable to parametricstatistical treatment.
The obtainedrange of scores in all cases was con-siderably less
than the potentialrange, suggesting that the scaleswere of ample
breadth to avoid ceil-ing restrictions. The medians of thePositive
and Negative Scales werestrikingly close (18 and 20,
respec-tively), and therefore the CompositeScale, representing
their differential,exhibited a median of -2, which indi-cated an
almost equal contributionby positive and negative items.
On the basis of the normality ofdistribution, it was possible
toconvert raw scores for each of thePANSS scales to percentile
ranks(table 2). This process enables provi-sional interpretation of
individualscores with reference to a medicatedchronic schizophrenic
sample.
Internal Consistency and Test-Re-test Reliability. The
reliability of the
Table 2. PANSS distribution based on sample of
101schizophrenics: Conversion of raw scores to percentile ranks
Raw score on PANSS scalePercentile
rank99.999989590858075706560555045403530252015105210.1
Positive37333129262524232221201918
1716151413121187
Negative40363432292827262524232221
201918171615141187
Composite211513107543210
- 1- 2- 4- 5- 6- 7- 8- 9- 1 1- 1 3- 1 5- 1 8- 2 0- 2 5
Generalpsychopathology
676058545048464443424039383635343331302826221816
NotePANSS - Positive and Negative Syndrome Scale.
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266 SCHIZOPHRENIA BULLETIN
Table 3. Internal reliability analysis of
Individual scale HemsPositive Scale
DelusionsConceptual disorganizationHallucinatory
behaviorExcitementGrandiositySuspiciousnessHostility
Scale total
Negative ScaleBlunted affectEmotional withdrawalPoor
rapportPassive-apathetic social withdrawalDifficulty in abstract
thinkingLack of spontaneity & flow of conversationStereotyped
thinking
Scale total
General Psychopathology ScaleSomatic concernAnxietyGuilt
feelingsTensionMannerisms & posturingDepressionMotor
retardationUncooperatJvenessUnusual thought
contentDisorientationPoor attentionLack of judgment &
insightDisturbance of volitionPoor impulse
controlPreoccupationActive social avoidance
Scale total
the PANSS
Mean
3.183.032.502.352.362.702.10
18.20 (
2.943.032.582.783.952.872.90
21.01 (
2.392.43 11.72 12.35 11.54 11.902.09 12.11 13.42 12.09 12.45
13.82 12.10 12.17 12.71 12.48 1
SD
1.52.42.70.24.56.24.14
5.08
.931.081.441.191.34.45.30
5.17
.21
.20
.06
.19
.12
.97
.10
.21
.49
.14
.28
.31
.30
.31
.18
.1837.74 9.49
Item-totalcorrelation
.78
.48
.66
.55
.64
.61
.59(a = .73,p
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VOL13.NO 2,1987 267
posite score, which thus representeda reasonable balance between
posi-tive and negative features.
The General PsychopathologyScale similarly revealed high
internalconsistency, producing an a coeffi-cient of .79 (p <
.001). Each of the 16component items contributed ho-mogeneously to
the scale (a rangedfrom .76 to .79 with single items re-moved) and
correlated significantlywith the total score (table 3).
The internal reliability of the Gen-eral Psychopathology Scale
couldfurther be evaluated by the split-halfmethod comparing odd and
evenitems. When the Spearman-Brownprophesy formula was used, the
re-liability coefficient from the sampleof 101 was .80 (p <
.001). This scalecorrelated substantially also with thePositive and
Negative Scales (r =.68 and .60, respectively, p < .001),whereas
its correlation with theComposite Scale was nonsignificant(r =
.07). Accordingly, both positiveand negative symptoms seemed tobe
potentiated by severity of globalillness, and in a
nondifferentiatingmanner.
From within the full sample it waspossible to study the
test-retest sta-bility and reliability of the PANSS 3-6 months
later in a cohort of 15 un-remitted patients who
remainedhospitalized on a research wardand, by inference, proved
refractoryto their ongoing neuroleptic treat-ment. Their initial
assessment re-vealed somewhat higher thanaverage scores on the
Positive,Negative, and General Psycho-pathology Scales (mean =
21.07,25.60, and 46.67, respectively). De-spite measurable clinical
gains dur-ing the intervening phase, asindicated by a small but
significantdrop of 4.74 points on the GeneralPsychopathology Scale
(correlatedt = 2.59, p < .05), the positive andnegative scores
were not noticeably
affected (mean = 21.13 and 26.27,respectively, p > .40). More
impor-tantly, the relative ordering ofPANSS scores between baseline
andfollowup held fairly constant overthis extended period, despite
the in-evitable clinical variations and secu-lar trends. For the
Positive,Negative, Composite, and GeneralPsychopathology Scales,
respec-tively, the test-retest Pearson cor-relations were .80 (p
< .001), .68(p < .01), .66 (p < .01), and .60(p < .02),
which corresponded to re-liability indexes ranging from .77 to.89
as estimates of their theoreticallytrue values (Garrett 1964).
Construct Validity. A direct inter-relationship of modest size
wasfound between the Positive andNegative Scales (r = .27, p <
.01),suggesting that the two syndromesare not independent.
However,their common association with gen-eral schizophrenic
pathology, as de-scribed above, raised the possibilitythat severity
of the disorder medi-ated the covariation between twootherwise
distinct scales. This prop-osition was supported by a
partialcorrelation which, upon extractingthe shared variance from
the Gen-eral Psychopathology Scale, re-vealed a significant
inversecorrelation between positive andnegative scores ( r ^ = -
.23, tv =2.37, p < .02). Thus, once the influ-ence of severity
of illness was re-moved statistically, the Positive andNegative
Scales tended to be mutu-ally exclusive. Because of the perva-sive
contribution of general severityof psychopathology, of course,
thetwo syndromes clinically can be ex-pected to overlap to some
degree.
Criterion-Related Validity. The dis-criminant and convergent
validity ofthe PANSS was supported by itscorrelations with a series
of clinical,
genealogical, psychometric, and his-torical assessments, as
reported byKay, Opler, and Fiszbein (1986).These data were analyzed
using sec-ond-order partial correlations to ad-just for age and
extrapyramidalsyndrome, as measured by the Ab-normal Involuntary
Movement Scale(National Institute of Mental Health1974) and
Extrapyramidal RatingScale (Alpert et al. 1978), since thesetwo
parameters covaried signifi-cantly with the negative pole of
theComposite Scale (r = .25 and- .26, respectively, p < .02).
The re-sults indicated that the Positive,Negative, and Composite
Scales ofthe PANSS were not influenced byextraneous variables such
as race,cultural group, chronicity of illness,depressive symptoms
(BPRS) or sadaffective tone (Manifest Affect Rat-ing Scale; Alpert
and Rush 1983),verbal intelligence (Quick Test; Am-mons and Ammons
1962), temporalattention (Span of Attention Test;Kay and Singh
1974), and percep-tual-motor development (Pro-gressive Figure
Drawing Test; Kay1982).
On the other hand, as sum-marized in table 4, the Positive
andNegative Scales produced distinctiveprofiles across the various
spheresof assessment, and many of the dif-ferences were
substantiated by sig-nificant correlations of dependentvariables
with the Composite Scale.Thus, the positive syndrome
wasdistinguished by unusual thoughts,anxiety, anger, preoccupation,
dis-orientation, labile affect, more fre-quent episodes of
hospitalization,and greater likelihood of sociopathyin first-degree
relatives. Conversely,the negative syndrome was charac-terized by
slowed motorium, deficitson several affective measures,thought
impoverishment, lessereducation, and dysfunction on
de-velopmentally based cognitive tests.
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268 SCHIZOPHRENIA BULLETIN
Table 4. Relationship of the PANSS to external variables
VariableDemographic/historical
Number of hospital admissionsYears of educationMale gender
Family history of illnessSociopathyUnspecified psychosisMajor
affective disorderTotal psychiatric illness
Cognitive/psychometricEgocentricity of Thought Test
(CDB)Random number fluencyColor Form Preference Test
(CDB)Affective (MARS)
Angry affective toneAffective labilityTotal affective
impairmentDull facial expressionImpoverished thought contentGlobal
unrelatednessLack of vocal emphasisSlow response latencyGlobal
immobilityLack of expressive gesturesSoft voice levelPoor eye
contactIncreased noncommunicative
movements
Clinical (BPRS)Unusual thought
contentAnxietyPreoccupationDisorientationMotor retardationSomatic
concern
Significant partial correlation (p
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VOL13.NO. 2,1887
both a productive syndrome (i.e.,anger and increased
noncom-municative movements) and deficits(e.g., dull facial
expression, pooreye contact, and emotional unre-latedness). In
terms of family psy-chiatric disorder, it correlated withpsychosis
as well as prevalence ofany major disturbance among first-degree
relatives (i.e., history ofschizophrenia, affective illness,
alco-holism, sociopathy, or suicide). Al-ternatively, it bore no
significantrelationship with the various controlmeasures such as
age, sex, maritalstatus, cultural group, chronicity ofillness,
verbal intelligence, or neu-rological soft signs.
In keeping with the impressionfrom the correlational
analyses,stepwise multiple regression re-vealed no overlap among
the param-eters that best accounted for thePositive and Negative
Scales. ThePositive Scale, with 74 percent of itsvariance
explained, was contributedto primarily by unusual thoughtcontent
(i.e., bizarre quality of idea-tion), family history of
sociopathy,angry affective tone, and global psy-chopathology. The
Negative Scale,with 81 percent of its variance ex-plained, was
accounted for chieflyby general affective impairment onthe Manifest
Affect Rating Scale,family history of psychosis, cogni-tive
developmental deficit on theEgocentricity of Thought Test
(Kay1982), impoverished thought con-tent, lack of insight, and
active so-cial withdrawal. For the CompositeScale, which denotes
tendency to-ward the positive or negative pole,69 percent of the
variance was pre-dicted by unusual thought content,emotional
unrelatedness, im-poverished thought content, yearsof education,
and conceptual de-velopment on the Color Form Rep-resentation Test
(Kay 1982). Themultiple correlation values for the
three scales were .86, .90, and .84,respectively, all highly
significant(p < .001).
Pharmacological Validation. Thevalidity and drug sensitivity of
thePANSS were examined experimen-tally by assessing differential
re-sponse of syndrome scores to drugtreatment.
In a single-subject experimentalstudy, we analyzed changes on
thePANSS when the dopamine precur-sor, L-dopa, was used
adjunctivelywith neuroleptics (Kay and Opler1985-86). The
investigation followeda 27-week double-blind, placebo-controlled,
reversal design. After 2weeks of treatment with neurolep-tics
alone, a haloperidol + placebocombination was instituted for
13weeks, followed by a haloperidol +L-dopa combination for thenext
8 weeks, and then a return tohaloperidol + placebo in the
remain-ing 5 weeks. When the interveningL-dopa phase was compared
againstthe preceding and following 4-weekphases, significant
improvementwas found on the Negative Scale ofthe PANSS (p < .05)
as well as twoof the individual negative items, dif-ficulty in
abstract thinking (p < .025)and passive-apathetic social
with-drawal (p < .05). By contrast, nei-ther the Positive Scale
nor any of itsindividual items showed changeduring the L-dopa
challenge(p > .50).
A second investigation consideredthe specificity of adverse
clinical re-action to anticholinergic drugs whenused with
neuroleptics. This workwas predicated on the findings ofSingh and
Kay (1975fl, 1975b, 1979)that antiparkinsonian agents tend toworsen
psychiatric symptoms ofneuroleptic-treated schizophrenics,and the
more recent qualification byJohnstone et al. (1983) that the
phe-nomenon obtains mainly to positive
features of the illness. Thus, Singh,Kay, and Opler (1987)
reanalyzedtheir earlier data on 47 well-definedschizophrenics who
had received,under double-blind conditions, anti-parkinsonian
medication (benz-tropine or trihexyphenidyl) for 2 to 4weeks along
the course of neurolep-tic treatment (haloperidol or
chlor-promazine). Clinical ratings duringthe antiparkinsonian phase
werecontrasted against the precedingand following 2-week periods
ofneuroleptic alone, thus controllingfor the time-series factor via
anABA' design (Singh and Kay 1978).The PANSS dusters were used
toinspect the data, which was possiblesince ratings on both the
BPRS andPRS had been conducted originally.Our results indicated
that only thePositive Scale was adversely influ-enced by the
anticholinergic inter-vention (t = 2.58, p < .02).
Thecorrelation between positive andnegative clusters in their
directionand magnitude of change provednonsignificant, suggesting
that thetwo scales did not covary in their re-sponse to
anticholinergics.
Typological Validation. The PANSShas been applied also as a
method ofcharacterizing schizophrenic pa-tients with a
predominantly positivevs. a predominantly negative syn-drome. We
considered patients whoscored "moderate" or higher on atleast three
of the seven positiveitems as positive-type schizo-phrenics and
those with the reversepattern ("moderate" on at leastthree negative
items) as negative-type schizophrenics; patients whoqualified for
both groups or neitherwere labeled as mixed type. Thissystem was
applied in separatestudies involving 37 acute (< 2 yearsof
illness) and 47 chronic schizo-phrenics, all with confirmed DSM-III
diagnosis (Lindenmayer, Kay,
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270 SCHIZOPHRENIA BULLETIN
and Opler 1984; Opler et al. 1984).The results supported the
validity
of the PANSS for isolating groupsthat differ on both antecedent
andconcurrent variables. A significantinverse relationship between
posi-tive and negative symptoms was ob-tained in both studies (r =
- .62,p < .001, and r = - .55, p < .01, re-spectively). In
the acute sample(Lindenmayer, Kay, and Opler1984), patients
classified by thePANSS as negative differed from thepositive group
in premorbid func-tioning (lesser schooling, p < .02;poorer work
adjustment, p < .10),likelihood of nonparanoid subdiag-nosis (p
< .02), and various deficitsymptoms that encompassed
thecognitive, social, affective, and mo-tor spheres. The chronic
study(Opler et al. 1984) also found thenegative type to have
achieved lesseducation (p < .02) and, on otherhistorical
dimensions, to be charac-terized more by winter birth(p < .02)
and early onset of illness(p < .05), as judged by age of
initialhospitalization. On objective psy-chometric tests, this
group was dis-tinguished by a developmentallymore primitive
cognitive style(p < .01) and slower psychomotorpace (p < .05)
on the Cognitive Di-agnostic Battery (Kay 1982), despitesimilar
scores on tests of intelligenceand visual-motor deficits. In
bothstudies, no group differences wereobtained on control variables
suchas sex, race, ethnic background,chronicity of illness, and
level ofgeneral psychopathology.
Typological comparisons wererendered also in the Singh, Kay,
andOpler (1987) study of clinical re-sponse to antiparkinsonian
agents.From the baseline drug-free assess-ment with the PANSS,
schizo-phrenic patients were prospectivelyclassified as
predominantly positive(n = 25) or negative type (n = 22)
according to the valence of theirComposite Scale score (i.e.,
positiveminus negative value above zerobeing positive and below
zero beingnegative). It was found that onlythose classified as
positive typeshowed subsequent clinical worsen-ing when
antiparkinsonian drugswere introduced (p < .02), while
thenegative group was essentially un-affected. Thus, complementing
thestudies of Lindenmayer, Kay, andOpler (1984) and Opler et al.
(1984),which supported the validity of thePANSS typology in
relation to ante-cedent and concurrent measures,the Singh, Kay, and
Opler (1987)finding introduced evidence of pre-dictive
validity.
DiscussionWe have described the developmentand initial
standardization of the 30-item PANSS as an instrument formeasuring
the prevalence of positiveand negative syndromes in schizo-phrenia.
A major impetus of its de-velopment was the need tor a
psy-chometrically sound procedure toserve typological and
dimensionalassessment. Perhaps its most impor-tant contributions
are the provisionof specified interview guidelines andassessment
criteria, and the inclu-sion of two additional scales thatconsider
positive-negative syn-dromes relative to one another andrelative to
general severity ofpsychopathology.
The PANSS method derives fromtwo established psychiatric
ratingscales for which interrater agree-ment and treatment
sensitivity havebeen demonstrated. As such, it pro-ceeds from
reliable techniques thatare familiar to clinicians and
re-searchers, requiring relatively littleadditional training. For
the purposeof the PANSS, however, precise op-
erational definitions were intro-duced for all items at every
ratinglevel. These guidelines, by enhanc-ing the objectivity and
replicabilityof observations, are expected toaugment concordance
among raters.Although this aspect of reliabilitycould not be
measured in the pres-ent study,2 the various other indica-tors of
reliability, stability, andvalidity from a sample of 101
schizo-phrenic patients suggested that thegoal of developing
objective andreplicable scales was met.
The PANSS scales, as already dis-cussed, were assembled mainly
onthe basis of theoretical and psycho-metric considerations (e.g.,
defini-tion of construct, content sampling,and balancing of items).
The presentempirical analyses indicated that theitems selected were
appropriate tothe constructs and were internallycoherent, yet it
also emerged thatother clinical variables could wellhave been
included. Specifically, ac-cording to correlational and
multipleregression analyses, a positive syn-drome was strongly
associated withunusual thought content and anx-iety, while a
negative syndromeseemed to encompass motor retar-dation, lack of
judgment and in-sight, and active social avoidance.
As based on the initial item selec-tion, however, the validation
proc-ess supported the use of thisinstrument for positive-negative
as-sessment. All four scales from thePANSS produced normal
Gaussiandistribution curves, which sug-gested amenability to
powerful para-metric statisticshence, reducedrisk of Type II error
in clinical re-
this article went to press, wehave reported interrater
reliabilities in arange between .83 and .87 for the fourPANSS
scales on a sample of 31 acuteschizophrenics (Kay, Opler, and
Linden-mayer, in press).
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VOL. 13, NO. 2,1987 271
search. The reliability of the PANSSwas upheld by coefficient a,
split-half analysis, and test-retestmethods, which also provided
someevidence of stability in a refractorychronic schizophrenic
cohort. Its va-lidity was considered on the basis offive separate
studies in which itserved typological and/or dimen-sional
assessment of schizophrenics.The studies supported its constructand
criterion-related validity withrespect to both antecedent and
con-current variables that involved his-torical, genealogical,
clinical, andpsychometric assessments.
The reliance on individual ratherthan team ratings raises the
questionof whether the outcomes may havebeen influenced by an
individual'spreconceptions. Such a possibilitywas mitigated by
several safeguardsin the design: the participation oftwo
independent psychiatrists, eachgathering data on approximatelyhalf
the sample; their lack of knowl-edge of PANSS scores when
collect-ing other data; their perception ofthe research as
exploratory ratherthan hypothesis testing; the use ofmultiple
external criteria, includingsuch measures as psychometric testsand
historical records that are objec-tive and derive from separate
andindependent sources; and, above all,the convergence of several
differentstudies, involving different ratersand designs, which
supportedvarious aspects of validation.
The pattern of findings also ac-corded with the results of
otherstudies, employing different inves-tigative tools, which have
similarlyimplicated lesser education, premor-bid impairments, poor
cognitive per-formance, and genealogicalpredisposition in the
characteriza-tion of a negative schizophrenic syn-drome (Andreasen
and Olsen 1982;Andreasen et al. 1982; Dworkin andLenzenweger 1984;
Pogue-Geile and
Harrow 1984). In these respects,there is some evidence of
cross-val-idation. In addition, predictive va-lidity and
sensitivity to change wereindicated by the significance of
thePositive and Negative Scales for an-ticipating and reflecting
differentialresponse to medication. The PANSSresearch, therefore,
was undertakenas a sequential programmatic seriesof studies that
included multi-method and experimental ap-proaches and, as such,
heeded themethodological requisites discussedby Sommers (1985) and
Zubin (1985)for validation of relatively unchartedconstructs.
The premise of our work was thatsome of the disparities in the
re-search on positive-negative distinc-tions may reflect the
application ofimprecise instruments, which pro-motes Type II error
by reducing thechance of observing true variance,and may be due
also to the very di-versity among studies in methods
ofassessment.
There has been considerable dis-agreement, for example,
surround-ing the issue of content validity, i.e.,what symptoms, how
many, andeven which spheres of functioningbest represent positive
and negativesyndromes (Sommers 1985). Thus,Angrist, Rotrosen, and
Gershon(1980) have measured these twosyndromes by using clusters of
10and 3 symptoms, respectively, whileAndreasen and Olsen (1982)
de-scribed instead 4 and 5 symptomsand Lewine, Fogg, and
Meltzer(1983) incorporated a compilation of22 and 11 symptoms.
WhereasOwens and Johnstone (1980) orig-inally conceived of the
negative syn-drome as entailing flat affect andimpoverished speech,
Crow (1980a)expanded the concept to includeavolition, and Andreasen
(1982)modified it by excluding poverty ofspeech and introducing
alogia,
anhedonia-asociality, and atten-tional impairment. Elsewhere
wehave proposed that attentional dys-function in schizophrenia is
multi-determined and at least partly afunction of arousal disorder
(Kay1981; Kay and Singh 1974), andstudies by our group and
othershave since confuted its specificity toeither the negative or
positive syn-drome (Opler et al. 1984; Bilder et al.1985; Cornblatt
et al. 1985; Kay,Opler, and Fiszbein 1986). By con-trast to other
descriptions of thenegative syndrome, the PANSS ex-cludes
attentional impairment butembraces deficits along five majorspheres
of functioning: the cogni-tive, affective, social,
interpersonal,and communicational.
Aside from variation in content ofscales, there has been little
studyand much disagreement about theconstruct validity of positive
andnegative syndromes (Zubin 1985).Researchers have differed in
theiropinion of whether these syndromesare independent of one
anotherhence, distinct constructsand gen-erally have ignored their
relation-ship to overall psychopathology.Andreasen and Olsen
(1982), for ex-ample, have argued that the positiveand negative
aspects represent op-posite poles of a continuum,whereas
Pogue-Geile and Harrow(1984) have concluded that they
areoverlapping features of schizo-phrenia. Our analysis of the
PANSSnot only supported the cohesivenessof the separate positive
and negativeclusters via coefficient a, butprovided evidence of
their dis-tinctiveness from one another by re-vealing low,
nonsignificant item-total cross-correlations (means of .17and .18)
and nonoverlap of determi-nants identified through multiple
re-gression analysis. However, therelationship between positive
andnegative dimensions was observed
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272 SCHIZOPHRENIA BULLETIN
to be strongly mediated by theirshared association with level of
psy-chopathology. Thus, a significant di-rect correlation was
initially foundbetween the Positive and NegativeScales, but when
their correlationswith the General PsychopathologyScale were
statistically extracted,they bore a significant inverse
cor-relation. This disclosure of the mu-tually exclusive nature of
thePositive and Negative Scales notonly supports their conceptual
sepa-rateness, i.e., construct validity, butprovides a compelling
rationale forpursuing typological study based onthis
distinction.
In view of the pattern of PANSScorrelations with historical,
cogni-tive developmental, and genealogi-cal variables, we have
proposed thatthe negative syndrome is dis-tinguished by a familial
predisposi-tion for psychosis and earlyontogenetic failures,
particularly inthe cognitive realm, which fore-shadow premorbid
adaptational dif-ficulties and, eventually, enduringmultimodal
deficits (Kay, Opler, andFiszbein 1985, 1986; Opler, Kay,
andFiszbein 1986). The results and inter-pretations are congruent
with thepivotal role ascribed to developmen-tal dysfunction in the
pathogenesisof certain expressions of schizo-phrenia (cf. Walker
and Emory 1983;Aylward, Walker, and Bettes 1984;Pogue-Geile and
Harrow 1984) andwith our dual-process model thatposits separate
developmental(neuroleptic-resistant) and arousal-related,
disorganizational (neurolep-tic-responsive) components to
theschizophrenic cognitive abnormality(Kay and Singh 1979).
Clearly, a systematic program ofstudy will be needed to pursue
thisemerging model. Further researchon the PANSS also is necessary,
in-cluding drug-free assessments andexpansion of the data base for
estab-
lishing norms. The latter objectiveentails comparisons of scores
amongschizophrenic subtypes, such asclassified by subdiagnosis
andchronicity of illness, as well as in re-lation to
nonschizophrenic groups.
It should be cautioned that gener-alization of results depends
on therepresentativeness of the sample,which in the present case
was achronic group in whom neuroleptictreatment could not be
withdrawn.With regard to chronicity, however,our analyses indicated
no significantcorrelation between years since ini-tial
hospitalization and positive syn-drome (r = - .03),
negativesyndrome (r = - .09), or the com-posite index (r = .04)
(Kay, Opler,and Fiszbein 1986). Evidence fromour typological
comparisons also re-vealed no covariation betweenlength of illness
and the positive-negative dimension as observedwithin an acute
(lindenmayer, Kay,and Opler 1984) or chronic schizo-phrenic
population (Opler et al.1984). In addition, we recently con-cluded
two studies which furthersuggest that positive and
negativesyndromes prevail to a similar ex-tent across various
stages of schizo-phrenia. A 2-year followup of 19acute
schizophrenics (Lindenmayer,Kay, and Friedman 1986)
revealednegligible change (p > .20) in posi-tive score (17.26 to
18.37), negativescore (22.05 to 21.16), composite in-dex (-4.29 to
-2.79), or generalpsychopathology (39.04 to 38.56). Bycontrast to
the present report of sta-bility among refractory patients dur-ing
the chronic phase, the correlateswere low and nonsignificant
whenscores were tracked from the acuteinto the subacute phase,
i.e., beforethe more established course of ill-ness (cf. Brown
1960). Thus, somepatients evidently improvedclinically, some
worsened, and somewere unchanged. In a cross-sec-
tional investigation of 134 schizo-phrenics (Kay et al. 1986),
whichpooled data from an acute sample(Lindenmayer, Kay, and Opler
1984)with the present group, we com-pared PANSS scores in the acute
(0-2 years), chronic (3-10 years), andlong-term chronic stages of
illness(> 10 years). Analysis of variance re-vealed
nonsignificant differences(F = 1) of means among these re-spective
groups on all scales: Posi-tive (18.76, 19.71, 17.98),
Negative(21.42, 21.21, 21.27), Composite(-2.66, -1.50, -3.29), and
GeneralPsychopathology (39.58, 37.40,38.13).
The assessment of neuroleptic-treated patients poses an
interpreta-tional problem for this as for otherpublished studies on
the positive-negative dimension. Particularly inevaluating the
negative syndrome, ithas been proposed that neurolepticsmay produce
a seeming indifferenceto the environment, and their sideeffects can
be misconstrued as mo-tor, affective, verbal, or
motivationaldeficits (Rifkin, Quitkin, and Klein1975; Van Putten
and May 1978). Toguard against systematic rating er-rors
attributable to extrapyramidalreaction, we separately assessedthese
symptoms on two side effectsscales and statistically partialed
outtheir influence on PANSS scores. Itwas seen that the
criterion-relatedvalidity was not diminished as a re-sult (Kay,
Opler, and Fiszbein 1986).The general impact of medicationand dose,
however, could not bestatistically adjusted due to in-complete and
unreliable informationin many cases. In our typologicalstudies,
where this information wasavailable, neuroleptic dose was
un-related to the positive-negative dis-tinction in acute
schizophrenics(Lindenmayer, Kay, and Opler 1984)and, contrary to
the proposed direc-tion of confound, was only half as
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VOL 13, NO. 2,1987 273
high for those with a preponderanceof negative features in a
chronicsample (Opler et al. 1984).
We are presently examining theinfluence of neuroleptic
treatmentand withdrawal on positive andnegative scores, their
variations overthe course of illness, their prognos-tic
implications, and their relation-ship to neurological status.
Inproceeding with our study of the re-liability and validity of the
PANSS,we also have begun to collect simul-taneous ratings from
paired ob-servers using this instrument as wellas corresponding
assessment withAndreasen's (1982) method, whichwill permit analysis
of interjudgeconcordance and cross-comparisonof scales (Kay, Opler,
and Linden-mayer, in press). Should the validityof the PANSS be
upheld by futurestudies and independent investiga-tors, its use
might be expected topromote uniformity and reliability inresearch
findings.
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Walker, E., and Emory, E. Infants atrisk for psychopathology:
Offspringof schizophrenic parents. Child De-velopment,
54:1269-1285, 1983.Zubin, J. Negative symptoms: Arethey indigenous
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AcknowledgmentWe thank Dr. Jean Endicott, Dr.Joseph Zubin, and
the editorial re-viewers of Schizophrenia Bulletin fortheir
constructive comments on anearlier draft of this article. A debt
ofgratitude is owed also to Dr. Man
Mohan Singh, whose conceptualiza-tion of schizophrenic phenomena
in-fluenced the definitions of manyscale items.
The Authors
Stanley R. Kay, Ph.D., is AssistantClinical Professor,
Department ofPsychiatry, Albert Einstein Collegeof
Medicine/Montefiore MedicalCenter, and Co-Director, ResearchUnit,
Bronx Psychiatric Center,Bronx, NY. Abraham Fiszbein,M.D., is
Resident in Psychiatry,
Albert Einstein College of Medicine/Montefiore Medical Center
andBronx Psychiatric Center, Bronx,NY. Lewis A. Opler, M.D., Ph.D.,
isAssociate Clinical Professor, Depart-ment of Psychiatry, Albert
EinsteinCollege of Medicine/MontefioreMedical Center, and Clinical
Direc-tor, Bronx Psychiatric Center, Bronx,NY. Dr. Opler has
recently accepteda position as Director of Schizo-phrenia Research,
Department ofPsychiatry, Presbyterian Hospital,and Associate
Professor of Psychia-try, College of Physicians and Sur-geons,
Columbia University, NewYork, NY.
Appendix Sample Items From the Positiveand Negative Syndrome
ScalePI. Delusions. Beliefs which are un-founded, unrealistic, and
idio-syncratic. Basis for rating: thoughtcontent expressed in the
inteviewand its influence on behavior.1. AbsentDefinition does not
ap-ply.2. MinimalQuestionable pathol-ogy; may be at the upper
extreme ofnormal limits.3. MildPresence of one or two de-lusions
that are vague, un-crystallized, and not tenaciouslyheld. Delusions
do not interferewith thinking, social relations, or be-havior.4.
ModeratePresence of either a ka-leidoscopic array of poorly
formed,unstable delusions or of a few well-formed delusions that
occasionally
interfere with thinking, social rela-tions, or behavior.5.
Moderate-severePresence of nu-merous well-formed delusions thatare
tenaciously held and occasion-ally interfere with thinking,
socialrelations, or behavior.6. SeverePresence of a stable set
ofdelusions that are crystallized, pos-sibly systematized,
tenaciously held,and clearly interfere with thinking,social
relations, and behavior. Pa-tient at times acts inappropriatelyand
irresponsibly on the basis of un-realistic beliefs.7.
ExtremePresence of a stable setof delusions that are either
highlysystematized or very numerous, anddominate major facets of
the pa-tient's life. This frequently results ininappropriate and
irresponsible ac-tion, which may even jeopardize thesafety of the
patient or others.
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SCHIZOPHRENIA BULLETIN
P2. Conceptual disorganization.Disorganized process of
thinkingcharacterized by disruption of goal-directed sequencing,
e.g., circum-stantiality, tangentiality, loose asso-ciations, non
sequiturs, grossillogicality, or thought blocking.Basis for rating:
cognitive-verbalprocesses observed during thecourse of interview.1.
AbsentDefinition does not ap-ply.2. MinimalQuestionable pathol-ogy;
may be at the upper extreme ofnormal limits.3. MildThinking is
circumstantial,tangential, or paralogical. There issome difficulty
in directing thoughtstoward a goal, and some looseningof
associations may be evidencedunder pressure.4. ModerateAble to
focus thoughtswhen communications are brief andstructured, but
becomes loose or ir-relevant when dealing with morecomplex
communications or whenunder minimal pressure.5.
Moderate-severeGenerally hasdifficulty organizing thoughts,
asevidenced by frequent irrelevancies,disconnectedness, or
loosening ofassociations even when not underpressure.6.
SevereThinking is seriously de-railed and internally
inconsistent,resulting in gross irrelevancies anddisruptions of
thought processes,which occur almost constantly.7. ExtremeThoughts
are disruptedto the point where the patient is in-coherent. There
is marked looseningof associations, which results in total
failure of communication, e.g.,"word salad" or mutism.Nl.
Blunted affect. Diminishedemotional responsiveness as
charac-terized by a reduction in facial ex-pression, modulation of
feelings,and communicative gestures. Basisfor rating: observation
of physicalmanifestations of affective tone andemotional
responsiveness duringthe course of interview.
1. AbsentDefinition does not ap-ply.2. MinimalQuestionable
pathol-ogy; may be at the upper extreme ofnormal limits.3.
MildChanges in facial expres-sion and communicative gesturesseem
stilted, forced, artificial, orlacking in modulation.4.
ModerateReduced range of facialexpression and few expressive
ges-tures.5. Moderate-severeAffect generallyappears "flat," with
few changes infacial expression and a paucity ofcommunicative
gestures.6. SevereMarked flatness and defi-ciency of emotions
exhibited most ofthe time. There may be unmodu-lated extreme
affective discharges,such as excitement, rage, or inap-propriate
uncontrolled laughter.7. ExtremeChanges in facial ex-pression and
evidence of commu-nicative gestures are virtuallyabsent. Patient
seems constantly toshow a barren or "wooden" expres-sion.N6. Lack
of spontaneity and flow ofconversation. Decrease in the nor-
mal flow of communication associ-ated with apathy,
avolition,defensiveness, or cognitive impair-ment. This is
manifested by dimin-ished fluidity and productivity ofthe
verbal-interactional process.Basis for rating:
cognitive-verbalprocesses observed during thecourse of
interview.
1. AbsentDefinition does not ap-ply.2. MinimalQuestionable
pathol-ogy; may be at the upper extreme ofnormal limits.3.
MildConversation shows littleinitiative. Patienf s answers tend
tobe brief and unembellished, requir-ing direct and leading
questions bythe interviewer.4. ModerateConversation lacks freeflow
and appears uneven or halting.Leading questions are
frequentlyneeded to elicit adequate responsesand proceed with
conversation.5. Moderate-severePatient shows amarked lack of
spontaneity andopenness, replying to the inter-viewer's questions
with only one ortwo brief sentences.6. SeverePatient's responses
arelimited mainly to a few words orshort phrases intended to avoid
orcurtail communication (e.g., "I don'tknow," "I'm not at liberty
to say").Conversation is seriously impairedas a result, and the
interview ishighly unproductive.
7. ExtremeVerbal output isrestricted to, at most, an
occasionalutterance, making conversation notpossible.