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VOL. 13, NO. 2 , 1 9 6 7 The Positive and Negative Syndrome Scale (PANSS) for Schizophrenia
by Stanley R. Kay, Abraham Flszbeln, and Lewis A. QpJer
Abstract
The variable results of positive- negative research with schizo- phrenics underscore the importance of well-characterized, standardized measurement techniques. We report on the development and initial standardization of the Positive and Negative Syndrome Scale (PANSS) for typological and dimensional as- sessment. Based on two established psychiatric rating systems, the 30- item PANSS was conceived as an operationalized, drug-sensitive in- strument that provides balanced representation of positive and nega- tive symptoms and gauges their re- lationship to one another and to global psychopathology. It thus constitutes four scales measuring positive and negative syndromes, their differential, and general sever- ity of illness. Study of 101 schizo- phrenics found the four scales to be normally distributed and supported their reliability and stability. Posi- tive and negative scores were in- versely correlated once their common association with general psychopathology was extracted, suggesting that they represent mu- tually exclusive constructs. Review of five studies involving the PANSS provided evidence of its cri- terion-related validity with anteced- ent, genealogical, and concurrent measures, its predictive validity, its drug sensitivity, and its utility for both typological and dimensional assessment.
Schizophrenia has long been re- garded as a heterogeneous entity, and over the decades researchers have sought consistent subpattems that might explain different aspects of this complex disorder. Most re- cently, Crow (1980a, 1980b) and An- dreasen (1982; Andreasen and Olsen 1982) have proposed that two dis-
tinct syndromes in schizophrenia can be discerned from the phe- nomenological profiles. The Type I, or positive, syndrome is composed of florid symptoms, such as delu- sions, hallucinations, and disor- ganized thinking, which are superimposed on the mental status. The Type II, or negative, syndrome is characterized by deficits in cogni- tive, affective, and social functions, including blunting of affect and pas- sive withdrawal.
It has been speculated that these syndromes in schizophrenia bear etiological, pharmacological, and prognostic import. Thus, Crow (1980a) conceived of the positive symptoms as an aspect of hyper- dopaminergia (hence, a neuroleptic- responsive disorder) in contrast to a structural brain deficit that was thought to underlie the negative symptoms. The research to date has provided some indirect support for this model (e.g., Johnstone et al. 1976, 1978a, 19786; Andreasen and Olsen 1982), but the diversity of re- sults has defied clear-cut interpreta- tions. For example, Angrist, Rotrosen, and Gershon (1980) noted that one of the three negative symp- toms assessed improved with neu- roleptics, and Andreasen et al. (1982) found none of five negative symptoms to be associated with ventricular size as assessed by com- puted tomography of schizophrenic patients. The distinctiveness of the syndromes and their stability over different phases of illness also have been questioned. Whereas An- dreasen and Olsen (1982) contended that positive and negative syn- dromes are "at opposite ends of a continuum," 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 significant interrelationship during the posthospitalization phase. Linden- mayer, Kay, and Friedman (1986) further demonstrated that the exter- nal correlates of positive and nega- tive syndromes among acute schizophrenics change over the course of 2 years.
Research findings, of course, are at best only as reliable and valid as the measures on which they are based. Thus, a fundamental source of variability that can account for the disparate results is the instrument used for positive-negative assess- ment. Well-characterized and stand- ardized techniques are a clear prerequisite for meaningful study of these syndromes, their relationship to other features of schizophrenia, and their response to medication. Although several carefully con- ceived scales have been devised re- cently (e.g., Andreasen and Olsen 1982; Lewine, Fogg, and Meltzer 1983; Heinrichs, Hanlon, and Car- penter 1984; lager, Kirch, and Wyatt 1985), none have undergone the thorough process of psychometric standardization that is necessary to address fundamental, and as yet highly contested, issues of content and construct validity (Sommers 1985). It has also been a matter of concern that to achieve satisfactory reliability and validity, more rigor is needed in providing strict opera- tional criteria for eliciting, defining, and measuring symptoms (Zubin 1985). Other limitations in some of the reported methods include the following: (1) evaluation of the pres- ence but not severity of component symptoms, (2) imbalance in the number of items representing posi- tive and negative facets, (3) inap- plicability for both typological and dimensional assessment of syn- dromes, (4) no evidence of sen- sitivity for monitoring drug-related
changes, (5) no measurement of the relative preponderance of positive versus negative symptoms, and (6) no measure of general psycho- pathology and its possible influence on the severity of positive and nega- tive syndromes.
The purpose of this study was to develop and standardize a well-de- fined instrument for positive-nega- tive assessment that attends to these methodological and psychometric considerations. In addition, we rec- ognized the need for a procedure that can be applied in relatively brief time (40-50 minutes), with minimal retraining and reorientation for the clinician, and that can be used re- peatedly for longitudinal or psycho- pharmacological assessment. We re- port here on the development and initial standardization of the Positive and Negative Syndrome Scale (PANSS) involving 101 schizo- phrenics and review evidence of its validity from five separate studies.
Methods
Subjects and Design. Patients with an unqualified diagnosis of schizo- phrenia were surveyed to assess the distribution, reliability, construct va- lidity, and criterion-related validity of the PANSS. The medical charts of inpatients from long-term psychi- atric units in a university-affiliated urban hospital were screened con- secutively to select those having a formal DSM-III diagnosis of schizo- phrenia (American Psychiatric Asso- ciation 1980). All cases with questionable diagnosis, known organic disorder, or mental retarda- tion were excluded. The remainder were interviewed on their own wards by one of two research psy- chiatrists to ascertain independently whether patients met DSM-11I crite- ria for schizophrenia. If diagnoses were thus confirmed, patients un- derwent the semiformalized PANSS
interview (infra) and were then as- sessed on the PANSS scales plus a series of measures deriving from clinical interview, cognitive testing, motor assessment, and careful re- view of medical and historical rec- ords. These measures are described in separate articles that chiefly ad- dress their relationship to positive and negative syndromes (Kay, Opler, and Fiszbein 1986; Opler, Kay, and Fiszbein 1986).
The assessments were conducted by two research psychiatrists, one of whom collected data on 47 patients and the other on 54. Both psychia- trists first underwent intensive train- ing in the PANSS interview and rating methods until satisfactory team concordance was achieved, and subsequently they rated pa- tients individually. The raters held no a priori assumptions about the outcome of data and were unaware of results on the PANSS, which was undertaken before other measures but scored only after the conclusion of study.
The final sample consisted of 101 subjects of ages 20-68 (mean = 36.81, SD = 11.16), including 70 males, 31 females, 33 whites, 43 blacks, and 25 Hispanics. Twelve patients were married, 10 divorced, and the remainder single. Mean education was 10.09 years (SD = 2.92), with the range extending to 4 years of college in four cases. Twenty-nine subjects had a first-de- gree relative who was previously hospitalized for psychiatric treat- ment; schizophrenia was specified in five cases and affective disorder (depressive, manic, or bipolar) in 10 cases; alcohol abuse was reported in the nuclear family of 16 patients; and among 13 subjects there was ev- idence of family sociopathy, as judged by record of criminal be- havior and prosecution.
On the average, patients were
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first hospitalized at age 22.39 years (SD = 8.63) and had since been ill for 14.41 years (SD = 8.95), with a median of six separate admissions. Over the past year and a half, 67.4 percent of the sample experienced continuous hospitalization, while for the remainder the mean duration of inpatient stay was 195 days. All were receiving neuroleptic medica- tion in standard dose ranges at the time of study.
Assessment Procedure. The PANSS ratings are based on all information pertaining to a specified period, usually the previous week. The in- formation derives from both clinical interview and reports of primary care staff (if institutionalized) or family members. The latter is the es- sential source for assessing social impairment, including items of im- pulse control, hostility, passive withdrawal, and active social avoid- ance. All other ratings accrue from a 30- to 40-minute semiformalized psychiatric interview that permits direct observation of affective, mo- tor, cognitive, perceptual, atten- tional, integrative, and interactive functions. The interview may be conceptualized as involving four phases.1
In the first 10-15 minutes, patients are encouraged to discuss their his- tory, circumstances surrounding their hospitalization, their current life situation, and their symptoms. The object of this phase is to estab- lish rapport and allow the patient to express 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 point descriptions, and rating form, is avail- able on request from the authors.
posture to observe, as unobtrusively as possible, the nature of thought processes and content, judgment and insight, communication and rapport, and affective and motor re- sponses.
Deviant material from the first segment of the interview is probed during the second phase, lasting an- other 10-15 minutes, through pro- totypic leading questions that progress from unprovocative, non- specific inquiry (e.g., How do you compare to the average person? Are you special in some ways?) to more direct probe of pathological themes (e.g., Do you have special or un- usual powers? Do you consider yourself famous? Are you on a spe- cial mission from God?). The object now is to assess productive symp- toms that can be judged from the patient's report and elaborations thereof, such as hallucinations, de- lusional ideation, suspiciousness, and grandiosity. For this purpose, the interviewer attempts to establish first the presence of symptoms and next their severity, which is gener- ally weighted according to the prominence of abnormal manifesta- tions, their frequency of occurrence, and their disruptive impact on daily functioning.
The third and most focused phase of the interview, requiring another 5-10 minutes, involves a series of specific questions to secure informa- tion on mood state, anxiety, orienta- tion to three spheres, and abstract reasoning ability. The evaluation of abstract reasoning, for example, consists of a range of questions on concept formulation (e.g., How are a train and bus alike?) and proverb interpretation, which are varied in content when using the PANSS for repeated assessment.
After all the essential rating infor- mation is obtained, the final 5-10 minutes of the interview are allo-
cated for more directive and forceful probing of areas where the patient appeared defensive, ambivalent, or uncooperative. For example, a pa- tient who avoided forthright ac- knowledgment of having a psychiatric disorder may be chal- lenged for a decisive statement. In this last phase, therefore, the patient is subjected to greater stress and testing of limits, which may be nec- essary to proceed beyond the social demand characteristics inherent in the interview situation and to ex- plore susceptibility to disorganiza- tion.
The interview procedure thereby lends itself to observation of physi- cal manifestations (e.g., tension, mannerisms and posturing, excite- ment, and blunting of affect), inter- personal behavior (e.g., poor rapport, 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, and delusions), and response to struc- tured questioning (e.g., disorienta- tion, anxiety, depression, and difficulty in abstract thinking).
Positive and Negative Syndrome Scale (PANSS). Data elicited by this assessment procedure are applied to the PANSS, a 30-item, 7-point rating instrument that has adapted 18 items from the Brief Psychiatric Rat- ing Scale (BPRS) (Overall and Gorham 1962) and 12 items from the Psychopathology Rating Schedule (PRS) (Singh and Kay 1975a). Each item on the PANSS is accompanied by a complete definition as well as detailed anchoring criteria for all seven rating points, which represent increasing 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 the PANSS appear in the Appendix, and scoring is performed on a sepa- rate rating form in consultation with the Rating Manual.
In assigning ratings, one first re- fers to the item definition to deter- mine presence of a symptom. The severity of an item, if present, is then judged by using a holistic per- spective in deciding which anchor- ing point best characterizes the patient's functioning, whether or not all elements of the description are observed. The highest applicable rating point is always assigned, even if the patient meets criteria for lower ratings as well.
Of the 30 psychiatric parameters assessed on the PANSS, seven were chosen a priori to constitute a Posi- tive Scale, seven a Negative Scale, and the remaining 16 a General Psy- chopathology Scale (see table 3 for the listing of component items).
The selection of items was guided by five considerations, in the follow- ing order of importance: (1) Items must be consistent with the hypo- thetical construct, i.e., with the the- oretical concept of positive and negative psychopathology as repre- senting productive features super- added to the mental status vs. deficit features characterized by loss of functioning (cf. Andreasen and Olsen 1982). (2) As per Carpenter, Heinrichs, and Alphs (1985), items should comprise symptoms whose classification as positive or negative is unambiguous and which, by most accounts, are regarded as primary rather than derivative (as, for exam- ple, impaired attention, disorienta- tion, and preoccupation may be secondary to arousal disorder or hal- lucinations). (3) They should be rep- resentative of different spheres of functioning (e.g., cognitive, affec- tive, social, and communicative) to
optimize content validity. (4) To the extent possible, they should include symptoms consensually regarded as crucial 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 and psychometric reasons, such as facili- tating cross-comparisons and equal- izing reliability potential, the numbers of items included in the positive and negative scales should be the same.
Insofar as this approach was de- termined by theoretical and heuristic considerations, there was no cer- tainty that all chosen items would be equally 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 Psychopathology Scale was included as an important adjunct to the positive-negative as- sessment since it provides a separate but parallel measure of severity of schizophrenic illness that can serve as a point of reference, or control measure, 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 which also was to be determined by this study), but only that it may be used as a yardstick of collective non- specific symptoms against which to judge severity of distinct positive and negative manifestations.
In addition to these three scales, a bipolar Composite Scale was con- ceived to express the direction and magnitude of difference between positive and negative syndromes. This score was considered to reflect the degree of predominance of one syndrome over the other, and its valence (positive or negative) may serve for typological characteriza- tion.
The PANSS is scored by summa- tion of ratings across items, such that the potential ranges are 7-49 for the Positive and Negative Scales and 16-112 for the General Psycho- pathology Scale. The Composite Scale is arrived at by subtracting the negative from positive score, thus yielding a bipolar index that ranges from -42 to +42.
Results
Distribution of Scores. Table 1 sum- marizes the distribution characteris- tics of the four scales from the
Table 1. Distribution characteristics of the PANSS for 101 schizophrenics
Distribution characteristics
Mean Median SD Range (potential)
Range (obtained) Skewness Kurtosis
Positive
18.20 18 6.08 7 to 49
7 to 32 .07
- . 9 7
Negative
21.01 20 6.17 7 to 49
8 to 38 .48 .06
PANSS scale
Composite
- 2.69 - 2
7.45 - 4 2 to + 4 2
- 2 5 to +13 - .45
.13
General psychopathology
37.74 36
9.49 16to112 19 to 63
.23 - . 3 0
NotB—PANSS = 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 of the Positive and Negative Syndrome Scale (PANSS)
401-
30 -> o z LJJ
o a i OC u. 10 -
20 -
-
i—r i .
COMPOSITE POSITIVE NEGATIVE GENERAL PSYCHOPATHOLOGY
• A Jr\ ••••-••• K../-; ,̂x"x-,....
-25 -17 - 9 -1 15 23 31
PANSS SCORE
39 47 55 63
PANSS was examined using coeffi- cient a to analyze its internal consis- tency and the contribution of the component items. As detailed in table 3, each of the items making up the Positive and Negative Scales cor- related very strongly with the scale total (p < .001), and the mean item- total correlations of .62 and .70, re- spectively, far exceeded the cross- correlations of .17 (Positive items with Negative Scale) and .18 (Nega- tive items with Positive Scale). The a coefficients with single items re- moved ranged from .64 to .84, and no perceptible gain on either scale
PANSS, and the full spectrum of scores is illustrated in figure 1. All four measures exhibited a roughly normal distribution pattern, without substantial skewness or kurtosis. This observation suggested that the constructs in question represent typ- ical continua and that their measure- ment is amenable to parametric statistical treatment. The obtained range of scores in all cases was con- siderably less than the potential range, suggesting that the scales were of ample breadth to avoid ceil- ing restrictions. The medians of the Positive and Negative Scales were strikingly close (18 and 20, respec- tively), and therefore the Composite Scale, representing their differential, exhibited a median of -2, which indi- cated an almost equal contribution by positive and negative items.
On the basis of the normality of distribution, it was possible to convert raw scores for each of the PANSS scales to percentile ranks (table 2). This process enables provi- sional interpretation of individual scores with reference to a medicated chronic schizophrenic sample.
Internal Consistency and Test-Re- test Reliability. The reliability of the
Table 2. PANSS distribution based on sample of 101 schizophrenics: Conversion of raw scores to percentile ranks
Raw score on PANSS scale
Percentile rank
99.9 99 98 95 90 85 80 75 70 65 60 55 50 45 40 35 30 25 20 15 10 5 2 1 0.1
Positive
37 33 31 29 26 25 24 23 22 21 20 19 18 — 17 16 15 14 13 12 11 8 7
— —
Negative
40 36 34 32 29 28 27 26 25 24 23 22 21 — 20 19 18 17 16 15 14 11 8 7
—
Composite
21 15 13 10 7 5 4 3 2 1 0
- 1 - 2 - 4 - 5 - 6 - 7 - 8 - 9 - 1 1 - 1 3 - 1 5 - 1 8 - 2 0 - 2 5
General psychopathology
67 60 58 54 50 48 46 44 43 42 40 39 38 36 35 34 33 31 30 28 26 22 18 16 —
Note—PANSS - Positive and Negative Syndrome Scale.
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266 SCHIZOPHRENIA BULLETIN
Table 3. Internal reliability analysis of
Individual scale Hems
Positive Scale Delusions Conceptual disorganization Hallucinatory behavior Excitement Grandiosity Suspiciousness Hostility
Scale total
Negative Scale Blunted affect Emotional withdrawal Poor rapport Passive-apathetic social withdrawal Difficulty in abstract thinking Lack of spontaneity & flow of conversation Stereotyped thinking
Scale total
General Psychopathology Scale Somatic concern Anxiety Guilt feelings Tension Mannerisms & posturing Depression Motor retardation UncooperatJveness Unusual thought content Disorientation Poor attention Lack of judgment & insight Disturbance of volition Poor impulse control Preoccupation Active social avoidance
Scale total
the PANSS
Mean
3.18 3.03 2.50 2.35 2.36 2.70 2.10
18.20 (
2.94 3.03 2.58 2.78 3.95 2.87 2.90
21.01 (
2.39 2.43 1 1.72 1 2.35 1 1.54 1 1.90 2.09 1 2.11 1 3.42 1 2.09 1 2.45 1 3.82 1 2.10 1 2.17 1 2.71 1 2.48 1
SD
1.52 .42 .70 .24 .56 .24 .14
5.08
.93 1.08 1.44 1.19 1.34 .45 .30
5.17
.21
.20
.06
.19
.12
.97
.10
.21
.49
.14
.28
.31
.30
.31
.18
.18 37.74 9.49
Item-total correlation
.78
.48
.66
.55
.64
.61
.59 (a = .73, p<.001)
.63
.78
.76
.79
.61
.86
.50 (a = .83, p<.001)
.48
.60
.23
.70
.33
.24
.27
.51
.51
.42
.65
.35
.66
.66
.60
.43 (a = .79, p < . 0 0 1 )
P
<.001 <.001 <.001 <.001 <.001 <.001 <.001
<.001 <.001 <.OO1 <.001 <.001 <001 <.001
<.001 <.001 <.O2 <.001 <.001 <.O2 <.01 <.001 <.001 <.001 <.001 <.001 <.001 <.001 <.001 <.001
a coefficient with Item deleted
.64
.73
.70
.71
.73
.69
.70
.81
.78
.79
.78
.82
.76
.84
.77
.77
.79
.76
.79
.79
.79
.78
.78
.78
.76
.79
.76
.76
.76
.78
Note.—PANSS = Positive and Negative Syndrome Scale.
could be achieved by discarding any item. Overall, the a coefficients for the Positive and Negative Scales were .73 and .83, respectively
(p < .001). As expected, both scales corre-
lated strongly with the Composite Scale, and they yielded coefficients
of similar magnitude (r = .59 and - .61, respectively, p < .001). This again indicated that the two scales contributed equivalently to the com-
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VOL13.NO 2,1987 267
posite score, which thus represented a reasonable balance between posi- tive and negative features.
The General Psychopathology Scale similarly revealed high internal consistency, producing an a coeffi- cient of .79 (p < .001). Each of the 16 component items contributed ho- mogeneously to the scale (a ranged from .76 to .79 with single items re- moved) and correlated significantly with the total score (table 3).
The internal reliability of the Gen- eral Psychopathology Scale could further be evaluated by the split-half method comparing odd and even items. When the Spearman-Brown prophesy formula was used, the re- liability coefficient from the sample of 101 was .80 (p < .001). This scale correlated substantially also with the Positive and Negative Scales (r = .68 and .60, respectively, p < .001), whereas its correlation with the Composite Scale was nonsignificant (r = .07). Accordingly, both positive and negative symptoms seemed to be potentiated by severity of global illness, and in a nondifferentiating manner.
From within the full sample it was possible 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 remained hospitalized on a research ward and, by inference, proved refractory to their ongoing neuroleptic treat- ment. Their initial assessment re- vealed somewhat higher than average 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, as indicated by a small but significant drop of 4.74 points on the General Psychopathology Scale (correlated t = 2.59, p < .05), the positive and negative scores were not noticeably
affected (mean = 21.13 and 26.27, respectively, p > .40). More impor- tantly, the relative ordering of PANSS scores between baseline and followup held fairly constant over this extended period, despite the in- evitable clinical variations and secu- lar trends. For the Positive, Negative, Composite, and General Psychopathology 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 theoretically true values (Garrett 1964).
Construct Validity. A direct inter- relationship of modest size was found between the Positive and Negative Scales (r = .27, p < .01), suggesting that the two syndromes are not independent. However, their common association with gen- eral schizophrenic pathology, as de- scribed above, raised the possibility that severity of the disorder medi- ated the covariation between two otherwise distinct scales. This prop- osition was supported by a partial correlation which, upon extracting the shared variance from the Gen- eral Psychopathology Scale, re- vealed a significant inverse correlation between positive and negative scores ( r ^ = - .23, tv = 2.37, p < .02). Thus, once the influ- ence of severity of illness was re- moved statistically, the Positive and Negative Scales tended to be mutu- ally exclusive. Because of the perva- sive contribution of general severity of psychopathology, of course, the two syndromes clinically can be ex- pected to overlap to some degree.
Criterion-Related Validity. The dis- criminant and convergent validity of the PANSS was supported by its correlations with a series of clinical,
genealogical, psychometric, and his- torical assessments, as reported by Kay, Opler, and Fiszbein (1986). These data were analyzed using sec- ond-order partial correlations to ad- just for age and extrapyramidal syndrome, as measured by the Ab- normal Involuntary Movement Scale (National Institute of Mental Health 1974) and Extrapyramidal Rating Scale (Alpert et al. 1978), since these two parameters covaried signifi- cantly with the negative pole of the Composite Scale (r = — .25 and - .26, respectively, p < .02). The re- sults indicated that the Positive, Negative, and Composite Scales of the PANSS were not influenced by extraneous variables such as race, cultural group, chronicity of illness, depressive symptoms (BPRS) or sad affective tone (Manifest Affect Rat- ing Scale; Alpert and Rush 1983), verbal intelligence (Quick Test; Am- mons and Ammons 1962), temporal attention (Span of Attention Test; Kay and Singh 1974), and percep- tual-motor development (Pro- gressive Figure Drawing Test; Kay 1982).
On the other hand, as sum- marized in table 4, the Positive and Negative Scales produced distinctive profiles across the various spheres of assessment, and many of the dif- ferences were substantiated by sig- nificant correlations of dependent variables with the Composite Scale. Thus, the positive syndrome was distinguished by unusual thoughts, anxiety, anger, preoccupation, dis- orientation, labile affect, more fre- quent episodes of hospitalization, and greater likelihood of sociopathy in first-degree relatives. Conversely, the negative syndrome was charac- terized by slowed motorium, deficits on several affective measures, thought impoverishment, lesser education, and dysfunction on de- velopmentally based cognitive tests.
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268 SCHIZOPHRENIA BULLETIN
Table 4. Relationship of the PANSS to external variables
Variable
Demographic/historical Number of hospital admissions Years of education Male gender
Family history of illness Sociopathy Unspecified psychosis Major affective disorder Total psychiatric illness
Cognitive/psychometric Egocentricity of Thought Test
(CDB) Random number fluency Color Form Preference Test
(CDB)
Affective (MARS) Angry affective tone Affective lability Total affective impairment Dull facial expression Impoverished thought content Global unrelatedness Lack of vocal emphasis Slow response latency Global immobility Lack of expressive gestures Soft voice level Poor eye contact Increased noncommunicative
movements
Clinical (BPRS) Unusual thought content Anxiety Preoccupation Disorientation Motor retardation Somatic concern
Significant partial correlation (p<.05)
Positive
.20
.21
.46
.31
.73
.38
.28
.26
Negative
- . 2 9 .21
.29 -.21
- . 3 4 - . 3 3
.64
.54
.52
.50
.49
.47
.43
.41
.32
.22
.20
Com- posite
.33
.24
.39
.27
.23
- . 4 1 - . 4 0 - . 4 9 - . 4 2 - . 4 0 - . 3 6 - . 4 3 - . 3 7 - . 3 0
.50
.33
- . 2 8
General psychopathology
.28
.20
.47
.24
.27
.30
.39
.46
.41
— — — — — —
Note—Based on study of 101 chronic schizophrenics (Kay, Opter & Rszbein 1986). Shown are the significant (p<.05) nonovertapping covartates of the Positive and Negative Scales and the correlates of the Composite and General Psychopathology Scales, excluding those clinical items that enter Into the latter scale. Abbreviations.—COB - Cognitive Diagnostic Battery (Kay1982); MARS - Manifest Affect Rating Scale (Alpert and Rush 1983); BPRS - Brief Psychiatric Rating Scale (Overall and Gorham 1962); PANSS - Positive and Negative Syndrome Scale.
It prevailed especially among males from families with history of psy- chotic disorder but not affective ill- ness. The positive-negative distinction on the PANSS, accord- ingly, was sustained along familial, antecedent, and concurrent assess- ments and suggested a more per- nicious disease process for the negative syndrome, one devolving from genealogical and ontogenetic sources (Kay, Opler, and Fiszbein 1985; Opler and Kay 1985; Opler, Kay, and Fiszbein 1986). A com- parison of results with simple vs. partial correlations suggested that these findings were not mitigated by neuroleptic-induced side effects (Kay, Opler, and Fiszbein 1986).
Because of the number of correla- tions performed, the reliability of in- dividual coefficients must be interpreted with due caution. The finding of a statistically significant relationship in a large sample, more- over, does not presuppose substan- tial shared variance between measures, which may be judged by the magnitude of the squared coeffi- cients of correlation. What stands out as important for the present pur- poses, however, is the general pat- tern of correlations rather than the individual values. The extensiveness of significant associations, the con- sistency across different spheres and methods of assessment, the concep- tual cohesiveness, and the corre- sponding unrelatedness of PANSS scores to extraneous variables may be regarded as evidence toward con- vergent and discriminant validity.
The General Psychopathology Scale, by comparison, yielded fewer external correlations and a non- specific profile that encompassed both positive and negative charac- teristics (table 4). As a measure of severity of illness, the scale was sig- nificantly associated with seven of the affective symptoms reflecting
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both a productive syndrome (i.e., anger and increased noncom- municative movements) and deficits (e.g., dull facial expression, poor eye contact, and emotional unre- latedness). In terms of family psy- chiatric disorder, it correlated with psychosis as well as prevalence of any major disturbance among first- degree relatives (i.e., history of schizophrenia, affective illness, alco- holism, sociopathy, or suicide). Al- ternatively, it bore no significant relationship with the various control measures such as age, sex, marital status, cultural group, chronicity of illness, verbal intelligence, or neu- rological soft signs.
In keeping with the impression from the correlational analyses, stepwise multiple regression re- vealed no overlap among the param- eters that best accounted for the Positive and Negative Scales. The Positive Scale, with 74 percent of its variance explained, was contributed to primarily by unusual thought content (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 chiefly by general affective impairment on the Manifest Affect Rating Scale, family history of psychosis, cogni- tive developmental deficit on the Egocentricity of Thought Test (Kay 1982), impoverished thought con- tent, lack of insight, and active so- cial withdrawal. For the Composite Scale, 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, years of education, and conceptual de- velopment on the Color Form Rep- resentation Test (Kay 1982). The multiple correlation values for the
three scales were .86, .90, and .84, respectively, all highly significant (p < .001).
Pharmacological Validation. The validity and drug sensitivity of the PANSS were examined experimen- tally by assessing differential re- sponse of syndrome scores to drug treatment.
In a single-subject experimental study, we analyzed changes on the PANSS when the dopamine precur- sor, L-dopa, was used adjunctively with neuroleptics (Kay and Opler 1985-86). The investigation followed a 27-week double-blind, placebo- controlled, reversal design. After 2 weeks of treatment with neurolep- tics alone, a haloperidol + placebo combination was instituted for 13 weeks, followed by a haloperidol + L-dopa combination for the next 8 weeks, and then a return to haloperidol + placebo in the remain- ing 5 weeks. When the intervening L-dopa phase was compared against the preceding and following 4-week phases, significant improvement was found on the Negative Scale of the PANSS (p < .05) as well as two of 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 its individual items showed change during the L-dopa challenge (p > .50).
A second investigation considered the specificity of adverse clinical re- action to anticholinergic drugs when used with neuroleptics. This work was predicated on the findings of Singh and Kay (1975fl, 1975b, 1979) that antiparkinsonian agents tend to worsen psychiatric symptoms of neuroleptic-treated schizophrenics, and the more recent qualification by Johnstone et al. (1983) that the phe- nomenon obtains mainly to positive
features of the illness. Thus, Singh, Kay, and Opler (1987) reanalyzed their earlier data on 47 well-defined schizophrenics who had received, under double-blind conditions, anti- parkinsonian medication (benz- tropine or trihexyphenidyl) for 2 to 4 weeks along the course of neurolep- tic treatment (haloperidol or chlor- promazine). Clinical ratings during the antiparkinsonian phase were contrasted against the preceding and following 2-week periods of neuroleptic alone, thus controlling for the time-series factor via an ABA' design (Singh and Kay 1978). The PANSS dusters were used to inspect the data, which was possible since ratings on both the BPRS and PRS had been conducted originally. Our results indicated that only the Positive Scale was adversely influ- enced by the anticholinergic inter- vention (t = 2.58, p < .02). The correlation between positive and negative clusters in their direction and magnitude of change proved nonsignificant, suggesting that the two scales did not covary in their re- sponse to anticholinergics.
Typological Validation. The PANSS has been applied also as a method of characterizing schizophrenic pa- tients with a predominantly positive vs. a predominantly negative syn- drome. We considered patients who scored "moderate" or higher on at least three of the seven positive items as positive-type schizo- phrenics and those with the reverse pattern ("moderate" on at least three negative items) as negative- type schizophrenics; patients who qualified for both groups or neither were labeled as mixed type. This system was applied in separate studies involving 37 acute (< 2 years of illness) and 47 chronic schizo- phrenics, all with confirmed DSM- III diagnosis (Lindenmayer, Kay,
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and Opler 1984; Opler et al. 1984). The results supported the validity
of the PANSS for isolating groups that differ on both antecedent and concurrent variables. A significant inverse 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 Opler 1984), patients classified by the PANSS as negative differed from the positive group in premorbid func- tioning (lesser schooling, p < .02; poorer work adjustment, p < .10), likelihood of nonparanoid subdiag- nosis (p < .02), and various deficit symptoms that encompassed the cognitive, social, affective, and mo- tor spheres. The chronic study (Opler et al. 1984) also found the negative type to have achieved less education (p < .02) and, on other historical dimensions, to be charac- terized more by winter birth (p < .02) and early onset of illness (p < .05), as judged by age of initial hospitalization. On objective psy- chometric tests, this group was dis- tinguished by a developmentally more primitive cognitive style (p < .01) and slower psychomotor pace (p < .05) on the Cognitive Di- agnostic Battery (Kay 1982), despite similar scores on tests of intelligence and visual-motor deficits. In both studies, no group differences were obtained on control variables such as sex, race, ethnic background, chronicity of illness, and level of general psychopathology.
Typological comparisons were rendered also in the Singh, Kay, and Opler (1987) study of clinical re- sponse to antiparkinsonian agents. From the baseline drug-free assess- ment with the PANSS, schizo- phrenic patients were prospectively classified as predominantly positive (n = 25) or negative type (n = 22)
according to the valence of their Composite Scale score (i.e., positive minus negative value above zero being positive and below zero being negative). It was found that only those classified as positive type showed subsequent clinical worsen- ing when antiparkinsonian drugs were introduced (p < .02), while the negative group was essentially un- affected. Thus, complementing the studies of Lindenmayer, Kay, and Opler (1984) and Opler et al. (1984), which supported the validity of the PANSS typology in relation to ante- cedent and concurrent measures, the Singh, Kay, and Opler (1987) finding introduced evidence of pre- dictive validity.
Discussion
We have described the development and initial standardization of the 30- item PANSS as an instrument for measuring the prevalence of positive and negative syndromes in schizo- phrenia. A major impetus of its de- velopment was the need tor a psy- chometrically sound procedure to serve typological and dimensional assessment. Perhaps its most impor- tant contributions are the provision of specified interview guidelines and assessment criteria, and the inclu- sion of two additional scales that consider positive-negative syn- dromes relative to one another and relative to general severity of psychopathology.
The PANSS method derives from two established psychiatric rating scales for which interrater agree- ment and treatment sensitivity have been demonstrated. As such, it pro- ceeds from reliable techniques that are familiar to clinicians and re- searchers, requiring relatively little additional training. For the purpose of the PANSS, however, precise op-
erational definitions were intro- duced for all items at every rating level. These guidelines, by enhanc- ing the objectivity and replicability of observations, are expected to augment concordance among raters. Although this aspect of reliability could not be measured in the pres- ent study,2 the various other indica- tors of reliability, stability, and validity from a sample of 101 schizo- phrenic patients suggested that the goal of developing objective and replicable scales was met.
The PANSS scales, as already dis- cussed, were assembled mainly on the basis of theoretical and psycho- metric considerations (e.g., defini- tion of construct, content sampling, and balancing of items). The present empirical analyses indicated that the items selected were appropriate to the constructs and were internally coherent, yet it also emerged that other clinical variables could well have been included. Specifically, ac- cording to correlational and multiple regression analyses, a positive syn- drome was strongly associated with unusual thought content and anx- iety, while a negative syndrome seemed 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 this instrument for positive-negative as- sessment. All four scales from the PANSS produced normal Gaussian distribution curves, which sug- gested amenability to powerful para- metric statistics—hence, reduced risk of Type II error in clinical re-
this article went to press, we have reported interrater reliabilities in a range between .83 and .87 for the four PANSS scales on a sample of 31 acute schizophrenics (Kay, Opler, and Linden- mayer, in press).
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search. The reliability of the PANSS was upheld by coefficient a, split- half analysis, and test-retest methods, which also provided some evidence of stability in a refractory chronic schizophrenic cohort. Its va- lidity was considered on the basis of five separate studies in which it served typological and/or dimen- sional assessment of schizophrenics. The studies supported its construct and criterion-related validity with respect to both antecedent and con- current variables that involved his- torical, genealogical, clinical, and psychometric assessments.
The reliance on individual rather than team ratings raises the question of whether the outcomes may have been influenced by an individual's preconceptions. Such a possibility was mitigated by several safeguards in the design: the participation of two independent psychiatrists, each gathering data on approximately half the sample; their lack of knowl- edge of PANSS scores when collect- ing other data; their perception of the research as exploratory rather than hypothesis testing; the use of multiple external criteria, including such measures as psychometric tests and historical records that are objec- tive and derive from separate and independent sources; and, above all, the convergence of several different studies, involving different raters and designs, which supported various aspects of validation.
The pattern of findings also ac- corded with the results of other studies, employing different inves- tigative tools, which have similarly implicated lesser education, premor- bid impairments, poor cognitive per- formance, and genealogical predisposition in the characteriza- tion of a negative schizophrenic syn- drome (Andreasen and Olsen 1982; Andreasen et al. 1982; Dworkin and Lenzenweger 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 were indicated by the significance of the Positive and Negative Scales for an- ticipating and reflecting differential response to medication. The PANSS research, therefore, was undertaken as a sequential programmatic series of studies that included multi- method and experimental ap- proaches and, as such, heeded the methodological requisites discussed by Sommers (1985) and Zubin (1985) for validation of relatively uncharted constructs.
The premise of our work was that some of the disparities in the re- search on positive-negative distinc- tions may reflect the application of imprecise instruments, which pro- motes Type II error by reducing the chance of observing true variance, and may be due also to the very di- versity among studies in methods of assessment.
There has been considerable dis- agreement, for example, surround- ing the issue of content validity, i.e., what symptoms, how many, and even which spheres of functioning best represent positive and negative syndromes (Sommers 1985). Thus, Angrist, Rotrosen, and Gershon (1980) have measured these two syndromes by using clusters of 10 and 3 symptoms, respectively, while Andreasen and Olsen (1982) de- scribed instead 4 and 5 symptoms and Lewine, Fogg, and Meltzer (1983) incorporated a compilation of 22 and 11 symptoms. Whereas Owens and Johnstone (1980) orig- inally conceived of the negative syn- drome as entailing flat affect and impoverished speech, Crow (1980a) expanded the concept to include avolition, and Andreasen (1982) modified it by excluding poverty of speech and introducing alogia,
anhedonia-asociality, and atten- tional impairment. Elsewhere we have proposed that attentional dys- function in schizophrenia is multi- determined and at least partly a function of arousal disorder (Kay 1981; Kay and Singh 1974), and studies by our group and others have since confuted its specificity to either 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 the negative syndrome, the PANSS ex- cludes attentional impairment but embraces deficits along five major spheres of functioning: the cogni- tive, affective, social, interpersonal, and communicational.
Aside from variation in content of scales, there has been little study and much disagreement about the construct validity of positive and negative syndromes (Zubin 1985). Researchers have differed in their opinion of whether these syndromes are independent of one another— hence, distinct constructs—and gen- erally have ignored their relation- ship to overall psychopathology. Andreasen and Olsen (1982), for ex- ample, have argued that the positive and negative aspects represent op- posite poles of a continuum, whereas Pogue-Geile and Harrow (1984) have concluded that they are overlapping features of schizo- phrenia. Our analysis of the PANSS not only supported the cohesiveness of the separate positive and negative clusters via coefficient a, but provided evidence of their dis- tinctiveness from one another by re- vealing low, nonsignificant item- total cross-correlations (means of .17 and .18) and nonoverlap of determi- nants identified through multiple re- gression analysis. However, the relationship between positive and negative dimensions was observed
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to be strongly mediated by their shared association with level of psy- chopathology. Thus, a significant di- rect correlation was initially found between the Positive and Negative Scales, but when their correlations with the General Psychopathology Scale were statistically extracted, they bore a significant inverse cor- relation. This disclosure of the mu- tually exclusive nature of the Positive and Negative Scales not only supports their conceptual sepa- rateness, i.e., construct validity, but provides a compelling rationale for pursuing typological study based on this distinction.
In view of the pattern of PANSS correlations with historical, cogni- tive developmental, and genealogi- cal variables, we have proposed that the negative syndrome is dis- tinguished by a familial predisposi- tion for psychosis and early ontogenetic failures, particularly in the cognitive realm, which fore- shadow premorbid adaptational dif- ficulties and, eventually, enduring multimodal deficits (Kay, Opler, and Fiszbein 1985, 1986; Opler, Kay, and Fiszbein 1986). The results and inter- pretations are congruent with the pivotal role ascribed to developmen- tal dysfunction in the pathogenesis of certain expressions of schizo- phrenia (cf. Walker and Emory 1983; Aylward, Walker, and Bettes 1984; Pogue-Geile and Harrow 1984) and with our dual-process model that posits separate developmental (neuroleptic-resistant) and arousal- related, disorganizational (neurolep- tic-responsive) components to the schizophrenic cognitive abnormality (Kay and Singh 1979).
Clearly, a systematic program of study will be needed to pursue this emerging model. Further research on the PANSS also is necessary, in- cluding drug-free assessments and expansion of the data base for estab-
lishing norms. The latter objective entails comparisons of scores among schizophrenic subtypes, such as classified by subdiagnosis and chronicity of illness, as well as in re- lation to nonschizophrenic groups.
It should be cautioned that gener- alization of results depends on the representativeness of the sample, which in the present case was a chronic group in whom neuroleptic treatment could not be withdrawn. With regard to chronicity, however, our analyses indicated no significant correlation between years since ini- tial hospitalization and positive syn- drome (r = - .03), negative syndrome (r = - .09), or the com- posite index (r = .04) (Kay, Opler, and Fiszbein 1986). Evidence from our typological comparisons also re- vealed no covariation between length of illness and the positive- negative dimension as observed within 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 further suggest that positive and negative syndromes prevail to a similar ex- tent across various stages of schizo- phrenia. A 2-year followup of 19 acute schizophrenics (Lindenmayer, Kay, and Friedman 1986) revealed negligible change (p > .20) in posi- tive score (17.26 to 18.37), negative score (22.05 to 21.16), composite in- dex (-4.29 to -2.79), or general psychopathology (39.04 to 38.56). By contrast to the present report of sta- bility among refractory patients dur- ing the chronic phase, the correlates were low and nonsignificant when scores were tracked from the acute into the subacute phase, i.e., before the more established course of ill- ness (cf. Brown 1960). Thus, some patients evidently improved clinically, some worsened, and some were unchanged. In a cross-sec-
tional investigation of 134 schizo- phrenics (Kay et al. 1986), which pooled 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), and long-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 General Psychopathology (39.58, 37.40, 38.13).
The assessment of neuroleptic- treated patients poses an interpreta- tional problem for this as for other published studies on the positive- negative dimension. Particularly in evaluating the negative syndrome, it has been proposed that neuroleptics may produce a seeming indifference to the environment, and their side effects can be misconstrued as mo- tor, affective, verbal, or motivational deficits (Rifkin, Quitkin, and Klein 1975; Van Putten and May 1978). To guard against systematic rating er- rors attributable to extrapyramidal reaction, we separately assessed these symptoms on two side effects scales and statistically partialed out their influence on PANSS scores. It was seen that the criterion-related validity was not diminished as a re- sult (Kay, Opler, and Fiszbein 1986). The general impact of medication and dose, however, could not be statistically adjusted due to in- complete and unreliable information in many cases. In our typological studies, where this information was available, 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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high for those with a preponderance of negative features in a chronic sample (Opler et al. 1984).
We are presently examining the influence of neuroleptic treatment and withdrawal on positive and negative scores, their variations over the course of illness, their prognos- tic implications, and their relation- ship to neurological status. In proceeding 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 well as corresponding assessment with Andreasen's (1982) method, which will permit analysis of interjudge concordance and cross-comparison of scales (Kay, Opler, and Linden- mayer, in press). Should the validity of the PANSS be upheld by future studies and independent investiga- tors, its use might be expected to promote uniformity and reliability in research findings.
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Singh, M.M.; Kay, S.R.; and Opler, L.A. Anticholinergic-neuroleptic an- tagonism in terms of positive and negative symptoms of schizo- phrenia: Implications for psycho- biological subtyping. Psychological Medicine, 17:39-18, 1987. Sommers, A. A. "Negative symp- toms": Conceptual and meth- odological problems. Schizophrenia Bulletin, 11:364-379, 1985.
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Acknowledgment
We thank Dr. Jean Endicott, Dr. Joseph Zubin, and the editorial re- viewers of Schizophrenia Bulletin for their constructive comments on an earlier draft of this article. A debt of gratitude is owed also to Dr. Man
Mohan Singh, whose conceptualiza- tion of schizophrenic phenomena in- fluenced the definitions of many scale items.
The Authors
Stanley R. Kay, Ph.D., is Assistant Clinical Professor, Department of Psychiatry, Albert Einstein College of Medicine/Montefiore Medical Center, and Co-Director, Research Unit, Bronx Psychiatric Center, Bronx, NY. Abraham Fiszbein, M.D., is Resident in Psychiatry,
Albert Einstein College of Medicine/ Montefiore Medical Center and Bronx Psychiatric Center, Bronx, NY. Lewis A. Opler, M.D., Ph.D., is Associate Clinical Professor, Depart- ment of Psychiatry, Albert Einstein College of Medicine/Montefiore Medical Center, and Clinical Direc- tor, Bronx Psychiatric Center, Bronx, NY. Dr. Opler has recently accepted a position as Director of Schizo- phrenia Research, Department of Psychiatry, Presbyterian Hospital, and Associate Professor of Psychia- try, College of Physicians and Sur- geons, Columbia University, New York, NY.
Appendix Sample Items From the Positiveand Negative Syndrome Scale PI. Delusions. Beliefs which are un- founded, unrealistic, and idio- syncratic. Basis for rating: thought content expressed in the inteview and its influence on behavior.
1. Absent—Definition does not ap- ply.
2. Minimal—Questionable pathol- ogy; may be at the upper extreme of normal limits. 3. Mild—Presence of one or two de- lusions that are vague, un- crystallized, and not tenaciously held. Delusions do not interfere with thinking, social relations, or be- havior.
4. Moderate—Presence 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-severe—Presence of nu- merous well-formed delusions that are tenaciously held and occasion- ally interfere with thinking, social relations, or behavior.
6. Severe—Presence of a stable set of delusions that are crystallized, pos- sibly systematized, tenaciously held, and clearly interfere with thinking, social relations, and behavior. Pa- tient at times acts inappropriately and irresponsibly on the basis of un- realistic beliefs.
7. Extreme—Presence of a stable set of delusions that are either highly systematized or very numerous, and dominate major facets of the pa- tient's life. This frequently results in inappropriate and irresponsible ac- tion, which may even jeopardize the safety of the patient or others.
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P2. Conceptual disorganization. Disorganized process of thinking characterized by disruption of goal- directed sequencing, e.g., circum- stantiality, tangentiality, loose asso- ciations, non sequiturs, gross illogicality, or thought blocking. Basis for rating: cognitive-verbal processes observed during the course of interview.
1. Absent—Definition does not ap- ply. 2. Minimal—Questionable pathol- ogy; may be at the upper extreme of normal limits. 3. Mild—Thinking is circumstantial, tangential, or paralogical. There is some difficulty in directing thoughts toward a goal, and some loosening of associations may be evidenced under pressure.
4. Moderate—Able to focus thoughts when communications are brief and structured, but becomes loose or ir- relevant when dealing with more complex communications or when under minimal pressure.
5. Moderate-severe—Generally has difficulty organizing thoughts, as evidenced by frequent irrelevancies, disconnectedness, or loosening of associations even when not under pressure.
6. Severe—Thinking is seriously de- railed and internally inconsistent, resulting in gross irrelevancies and disruptions of thought processes, which occur almost constantly.
7. Extreme—Thoughts are disrupted to the point where the patient is in- coherent. There is marked loosening of associations, which results in total
failure of communication, e.g., "word salad" or mutism.
Nl. Blunted affect. Diminished emotional responsiveness as charac- terized by a reduction in facial ex- pression, modulation of feelings, and communicative gestures. Basis for rating: observation of physical manifestations of affective tone and emotional responsiveness during the course of interview.
1. Absent—Definition does not ap- ply. 2. Minimal—Questionable pathol- ogy; may be at the upper extreme of normal limits. 3. Mild—Changes in facial expres- sion and communicative gestures seem stilted, forced, artificial, or lacking in modulation.
4. Moderate—Reduced range of facial expression and few expressive ges- tures.
5. Moderate-severe—Affect generally appears "flat," with few changes in facial expression and a paucity of communicative gestures.
6. Severe—Marked flatness and defi- ciency of emotions exhibited most of the time. There may be unmodu- lated extreme affective discharges, such as excitement, rage, or inap- propriate uncontrolled laughter.
7. Extreme—Changes in facial ex- pression and evidence of commu- nicative gestures are virtually absent. Patient seems constantly to show a barren or "wooden" expres- sion.
N6. Lack of spontaneity and flow of conversation. 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 of the verbal-interactional process. Basis for rating: cognitive-verbal processes observed during the course of interview.
1. Absent—Definition does not ap- ply.
2. Minimal—Questionable pathol- ogy; may be at the upper extreme of normal limits.
3. Mild—Conversation shows little initiative. Patienf s answers tend to be brief and unembellished, requir- ing direct and leading questions by the interviewer.
4. Moderate—Conversation lacks free flow and appears uneven or halting. Leading questions are frequently needed to elicit adequate responses and proceed with conversation.
5. Moderate-severe—Patient shows a marked lack of spontaneity and openness, replying to the inter- viewer's questions with only one or two brief sentences.
6. Severe—Patient's responses are limited mainly to a few words or short phrases intended to avoid or curtail communication (e.g., "I don't know," "I'm not at liberty to say"). Conversation is seriously impaired as a result, and the interview is highly unproductive.
7. Extreme—Verbal output is restricted to, at most, an occasional utterance, making conversation not possible.
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