The social phobia and anxiety inventory: Concurrent and external validity

BERAVIORTHERAPY 20, 417-427, 1989

The Social Phobia and Anxiety Inventory: Concurrent and External Validity DEBORAH C . BEIDEL SAMUEL M . TURNER

MELINDA A. STANLEY CONSTANCE V . DANCU Western Psychlatrtc Institute and Chmc Umverstty of Pittsburgh School of Medwme The Social Phobia and Anxiety Inventory (SPAI) is a newly developed instrument to measure sooal phobia and somal anxiety. In this report, the concurrent and external validRy of the scale were examined. The results indicate that the SPAI successfully discriminates social phoblcs from non-social phobtcs, accurately predicts social distress, and has some ability to predict the occurrence o f speofic behaviors in social situations. In addition, the results suggest that the ratings made by a significant other closely matched the mdwidual's own ratings of social distress, indicating a degree of external vahdity.

Although social situations have long been recognized as a source of distress for some individuals, the concept of social phobia as a discrete diagnostic category has been in existence for less than a decade. Social phobia is defined as "a persistent fear of one or more situations in which the person is exposed to possible scrutiny by others and fears that he or she may do something or act in a way that will be humiliating or embarrassing" (Diagnostic and Statistical Manual o f Mental Disorders-Ill-Revised; American Psychiatric Association, 1987). The disorder is considered chronic and can significantly impair occupational, academic and/or social functioning (Turner, Beidel, Dancu, & Keys, 1986). Social phobia is perhaps the least understood and the least researched of the anxiety disorders. Although there are several scales available to measure social anxiety, most were constructed prior to the publication o f the Diagnostic and Statistical Manual of Mental Disorders-Ill (American Psychiatric Association, 1980) where the diagnostic criteria for social phobia were first This study was supported in part by N1MH Grants #41852, 30915, 18269 and 16884. Correspondence concerning this article and requests for a copy of the inventory should be addressed to S. M. Turner, Western Psychiatric Institute and Clinic, 3811 O'Hara Street, Pittsburgh, PA 15213. 417 0005-7894/89/0417-042751 00/0 Copyright 1989 by Associanon for Advancement of Behavior Therapy All rights of reproducUon m any form reserved

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introduced. As social anxiety is experienced by individuals with many psychiatric disorders, as well as normals (Turner & Beidel, 1989), these inventories may not adequately reflect the specific features of social phobia. The Social Phobia and Anxiety Inventory (SPAI; Turner, Beidel, Dancu, & Stanley, 1989) is a new, empirically derived self-report inventory which was developed as a more specific measure of social phobia. The SPAI was designed to assess somatic symptoms and cognitions characteristic o f social phobia and to measure anxiety, avoidance, and escape behaviors across a range o f potentially fear-producing social situations. The SPAI utilizes a Likert scale format to allow for assessment of symptom severity. In an initial investigation, it was found to have high test-retest reliability and good internal consistency (Turner et al., 1989). The SPAI appears to be sensitive to varying degrees of social anxiety and is capable of differentiating social phobics from other anxiety patients (Turner et al., 1989). In this report, the concurrent and external validity of the SPAI are addressed.

METHOD Subjects A total o f 182 subjects drawn from a sample o f 308 introductory psychology students were selected for study participation. These subjects were selected initially on the basis of a screening battery which consisted of the Social Avoidance and Distress Scale (SAD; Watson & Friend, 1969), the Fear of Negative Evaluation Scale (FNE; Watson & Friend, 1969), and both the state and trait scales o f the State-Trait Anxiety Inventory (STAI; Spielberger, Gorsuch, & Lushene, 1970). Inclusion into the non-socially anxious (NSA) group was based on scoring below the 50th percentile on each of the four instruments. Therefore, the NSA group had to have a score of: 40 or less on the STAI state scale; 38 or less on the STAI trait scale; 11 or less (for males) and 8 or less (for females) on the SAD; 13 or less (for males) and 16 or less (for females) on the FNE. Inclusion into the socially anxious (SA) group was based on scoring higher than the 50th percentile on each o f these scales. Using this procedure, 123 NSA subjects and 59 SA subjects were selected. All SA subjects participated in a brief diagnostic interview conducted by the first author to ensure that social distress resulted from fears or negative evaluation (Turner et al., 1989). Subsequently, the Anxiety Disorders Interview Schedule (ADIS; DiNardo et al., 1983) was administered to 51 of the SA subjects by the second or fourth author, both o f whom were blind to the subject's performance on the SPAI and the preliminary designation as SA or NSA. The ADIS is a structured interview schedule based on DSM-III criteria and is designed to assist in differential diagnosis among the anxiety disorders. O f particular interest in this study was the number of subjects who met DSM-III criteria for social phobia. Twenty-five percent o f the interviews were audiotaped and rated by a second experienced cli~aician who also was blind to all of the subjects' scale scores and diagnostic status. Using the Kappa coefficient, interrater reliability for diagnosis o f social phobia was .81. O f the 51 SA subjects who were interviewed with the ADIS 47 met DSM-III criteria for Social Phobia (SP).

VALIDITY OF IHI~ SPAI

419

TABLE 1 DEMOGRAPHIC DATA Non-Socially Anxious

Socially Anxious

Total

Mean Age

19.4

19.0

Sex Male Female

43 (35=70) 80 (65=70)

15 (25=70) 44 (75=7e)

58 (30=70) 124 (70=70)

Race t Black White Asian

7 (6=70) 82 (67=70) 1 (1=70)

4 (7=70) 34 (58=70) 2 (3=70)

11 (7=70) 116 (62°70) 3 (2=70)

Note.

i Data on

race w e r e

19.2

available only for 70=70 of the total sample.

There were three separate validity experiments included in this investigation. The NSA subjects were assigned randomly to one of the three validity studies. The entire sample of 51 socially anxious subjects who were interviewed with the ADIS were included in Study I (see below), and subsamples of these socially phobic subjects also were randomly assigned to either Study 2 or Study 3. The mean age of the sample was 19.2. There were no differences between the groups with respect to age, sex or racial composition. The demographic data are presented in Table 1. Assessment Instruments All subjects completed the SPAI which consists of 45 items divided into 2 subscales: one scale to assess social phobia and a second scale to assess agoraphobia. The total score is obtained by subtracting the agoraphobia subscale from the social phobia subscale, a procedure developed on the basis of theoretical and empirical distinctions between social phobia and agoraphobia. Inasmuch as many agoraphobics report fears in crowds and social settings, the difference score procedure allows one to "subtract out" any fears of social interactions that may result from fears of having a panic attack in a social situation. The use of this difference score enhances the ability of the SPAI to differentiate patients with social phobia from those with agoraphobia or obsessive compulsive disorder (Turner et at., 1989). A complete description of the inventory, rationale for the subscales, and scoring procedures can be found in Turner et at. (1989).

Validity Studies Validity Study 1 was designed to assess the SPArs concurrent validity by comparing reports of social phobia via two different reporting modalities: paper and pencil inventory (SPAI) and a clinical interview with an experienced clini-

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cian. Concurrent validity was also the purpose of Validity Study 2 in which the ability of the SPAI to describe accurately the subjects' behavior in daily social situations, was addressed. Validity Study 3 was designed to assess the external validity of the inventory. Although many of the components of social phobia are internal and non-observable, some characteristics such as social reticence and avoidance can be apparent to others, particularly significant others. If the SPAI assesses characteristics of social phobia, a "significant other" should be able to complete the inventory based on his/her knowledge of the subject's behavior, and score reasonably close to the subject's self-report. Validity S t u d y 1 Subjects and Procedure This study was designed to assess the concurrent validity of the SPAI. Eightyfive subjects participated in Study 1. Thirty-four NSA subjects were assigned randomly to this study, while all 51 SA subjects who had been interviewed with the ADIS were included in the analysis. These subjects represent a subsample of individuals described in an earlier investigation (Turner et al., 1989). All subjects were interviewed within two weeks after the screening session. The non-socially anxious subjects were interviewed with the ADIS in a manner identical to that of the socially phobic subjects described above. All subjects (NSA and SA) were interviewed in a random order. Following the administration of the ADIS, SPAI results for the individuals who met criteria for social phobia, were compared to scores of subjects who did not receive a diagnosis using a one-way ANOVA and a discriminant function analysis. Results Of the 85 subjects who participated in this study, 57 (67%, or 19% of the total sample originally assessed) met DSM-III criteria for a diagnosis of social phobia, a prevalence figure which is consistent with data on social anxiety from other college populations (e.g., Spielberger et al., 1984). "l~enty-four did not receive any DSM-III diagnosis, and 4 reported symptomatology that suggested a primary Axis II diagnosis. These latter 4 individuals were excluded from the data analysis. Scores on the social phobia subscale, agoraphobia subscale, and SPAI total scores were analyzed with separate Group (social phobia versus no social phobia) x Sex analyses of variance. On the social phobia subscale, there were main effects for group (F(1,80) = 122.9, p < .0005) and sex (F(1,80) = 5.43, p < .025). Social phobic subjects scored significantly higher than subjects who did not receive a diagnosis. In addition, in both groups, males scored significantly higher than females. On the agoraphobia subscale, there was a significant main effect for group. Social phobic subjects scored significantly higher than non-social phobics (F(1,80) = 10.52, p < .002). Finally, the results of the analysis for the SPAI total score indicated significant main effects for sex and group. Social phobics scored significantly higher than those subjects without a diagnosis (F(1,80) = 106.97, p < .0005), and males in both groups scored significantly higher than females (F(1,80) = 8.05, p <

VALIDITY OF lltlz SPAI

421

TABLE 2 SCORES OF SOCIAL PHOBICS AND NORMAL CONTROLS ON lU.~ SPAI SOCIAL PHOBIA SUBSCALE, AGORAPHOBIA SUBSCALE AND TOTAL SCOREI Social Phobics

Normals

SPAI

Males (n = 13)

Females (n = 37)

Males (n = 16)

Females (n = 18)

Social P h o b i a Subscale

106.08

96.81

56.25

42.33

A g o r a p h o b i a Subscale

25.31

26.00

16.63

18.50

Total Score

80.77

70.81

39.63

23.83

Note.

i F values a n d significance levels are given in text.

.01). Means for both groups on the two subscales and the total SPAI score are presented in Table 2. Additionally, a discriminant function analysis was conducted to evaluate the capability of the SPAI social phobia and agoraphobia subscales to predict group membership. Both subscale scores were entered into the analysis. The resultant discriminant function was significant (X2(1) = 19.26, p < .0001), yielding standardized canonical discriminant function coefficients of 1.06 for the social phobia subscale and -0.13 for the agoraphobia subscale. These data are summarized in Table 3. The total classification accuracy using a jackknifed classification procedure was 74.4070, with 74.1070 of the social phobic subjects and 75°70 of the non-social phobic subjects correctly classified on the basis of SPAI performance. Using the kappa statistic, the total classification accuracy is significantly better than chance alone (k = .46, p < .0005).

Validity Study 2 Subjects and Procedures Fifty-four subjects (17 SA and 34 NSA) were assigned randomly to Study 2. At the initial visit, subjects completed the SPAI and were asked to self monTABLE 3 DlSCI~NANT FUNCTION ANALYSIS USING SPAI PERFORMANCE TO PREDICT GROUP MEMBERSHIP Predicted G r o u p Membership Actual G r o u p

No. of Cases

Social Phobia

No Social P h o b i a

Social P h o b i a Diagnosis

57

N o Social P h o b i a Diagnosis

24

43 75.4~0 6 25.0%

14 24.6% 18 75.0%

Total Classification Accuracy = 74.4%

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itor their social behavior and social anxiety for a subsequent two-week period. The monitoring forms were those routinely used in the Anxiety Disorders Clinic at Western Psychiatric Institute and Clinic, and subjects were carefully instructed in the format of the monitoring sheets. They were given a two-week supply of monitoring forms and were requested to complete five ratings each night before going to sleep. Specific ratings included the following: (a) number of disturbing thoughts related to social encounters (0-25 +); (b) degree of distress experienced from the disturbing thoughts (0-8); (c) number of times in an anxiety-provoking social situation (0-25 +); (d) degree of distress in social situations (0-8), and (e) number of social situations avoided (0-25 +). The subjects returned the rating sheets after the two-week period. The ratings for frequency of disturbing thoughts, frequency of entry into social situations, and frequency of avoidance were each summed separately across the 14 days to derive 3 total frequency scores. Each total score served as the basis for data analysis. The 2 distress ratings were averaged across the 14-day period, resulting in 2 mean distress ratings. Results Preliminary analyses using Group x Sex ANOVAs for each of the selfmonitoring variables did not reveal any reporting differences based on the sex of the respondent (all p's > .05). Three SPAI criterion variables were calculated for each subject. These included: (a) a total SPAI score; (b) a SPAI cognitive score, and (c) a SPAI behavioral score. The cognitive and behavioral scores were based on the subjects' responses to items within the SPAI social phobia subscale which specifically tapped each of these dimensions. These items had been independently identified by two experienced clinicians as assessing either the cognitive or behavioral domain. The subjects' scores on each of the designated items were summed across all items in that dimension to create the SPAI cognitive and SPAI behavioral scores. All analyses were conducted using Pearson Product Moment Correlation coefficients. A total of five correlational analyses were conducted: distress in social situations with total SPAI score; frequency of disturbing thoughts with SPAI cognitive score; distress from disturbing thoughts with SPAI cognitive score; entry into social situations with the SPAI behavioral score and social situations avoided with the SPAI behavioral score. The results indicated that the total SPAI score was moderately correlated with daily ratings of general distress in social situations (r(52) = .47,p < .001). The SPAI cognitive score was modestly correlated with daily ratings of distress experienced from disturbing thoughts (r(54) = .30, p < .025), but the relationship between the SPAI cognitive score and number of disturbing thoughts was low, even though it approached statistical significance (r(52) = .23, p < .09). The SPAI behavioral score was modestly correlated with entry into anxiety-producing situations (r(54) = .31, p < .025). The relationship between the SPAI behavioral score and avoidance of social situations was low and not significant (r(54) = .19, p > .05). The lack of a significant correlation between these parameters may have been due to the relatively small number

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423

of subjects who reported consistent avoidance o f social situations, resulting in little variability on this dimension. Correlation coefficients for the SPAI were compared to two other commonly used instruments for the assessment of social anxiety, the Social Avoidance and Distress Scale (SAD) and the Fear o f Negative Evaluation Scale (FNE; Watson & Friend, 1969). The five daily diary ratings were correlated with the subjects' SAD and FNE scores using Pearson Product Moment Correlation Coefficients. Correlation coefficients for the relationship of daily behaviors with the SAD were as follows: rating o f general social distress, r (52) = .47, p < .001; frequency of disturbing thoughts, r (54) = -.03, p > .05; distress from disturbing thoughts, r (52) = .08, p > .05; frequency of entry into anxietyprovoking situations, r (54) = -.03, p > .05. Correlation coefficients for the relationship between the FNE and daily behaviors were as follows: rating o f general social distress, r (52) = .41, p < .0025; frequency of disturbing thoughts, r (54) = .08, p > .05; distress from disturbing thoughts, r (52) = .21, p > .05; frequency o f entry into anxiety-provoking situations, r (54) = .14, p > .05 and frequency o f situations avoided, r (54) = -.11, p > .05. Correlations on these latter two instruments were compared to those obtained with the SPAI using Fisher's r to Z transformation. Despite the difference in magnitude, correlations between the SPAI and the SAD or FNE were not statistically different (all p's > .05).

Validity Study 3 Subjects and Procedure At the initial visit, 62 subjects (20 SA and 41 NSA) were assigned randomly to Study 3 and scheduled for a second visit within two-weeks' time. At the initial visit, subjects completed the SPAI and were asked to name an individual whom they believed could complete the SPAI accurately based on his/her perception of the subject's behavior. Individuals named were parents, siblings, roommates, and boyfriends or girlfriends. Subjects were then given a copy of the SPAI to take to the individual named. Significant others were instructed to complete the inventory independently, without questioning the subject. The inventories were returned to the investigators by the subject at the second visit. At this time, the subjects were questioned about collaboration with the significant other in the completion o f the inventory. In three cases, collaboration was suspected, and these three subjects were excluded from the analysis.

Results The subject's SPAI total scores were correlated with those of the significant others using Pearson Product Moment Correlation coefficients. The results revealed a moderate and significant correlation of SPAI scores with ratings made by significant others (r (59) = .63, p < .0001). Correlations for males and females also were examined separately. In both groups, correlations between the subject's scoreand that o f the significant other were significant (r (42) = .74, p < .0001 for females; r (17) = .42, p < .05 for males). Using Fisher's

424

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r to Z transformation, these correlation coefficients were not significantly different (Z = 1.61, p > .05).

DISCUSSION In a previous report, the construction, test-retest reliability, and internal consistency of the SPAI were reported (Turner et al., 1989). In addition, the ability of the inventory to differentiate social phobics from other anxiety disorders patients was demonstrated. The results of the current study provide further support for the validity of the SPAI. Based on the results of Study 1, the SPAI appears capable of distinguishing subjects who meet DSM-III criteria for social phobia from non-social phobics. Subjects diagnosed as socially phobic scored significantly higher on the SPAI than subjects who did not receive the diagnosis. In addition, the discriminant function analysis indicated that 74°70 of the subjects were classified correctly using the two subscale scores. The negative coefficient associated with the agoraphobia score indicates that this scale has a suppressing effect, and supports the use of the "difference" score procedure. Although the 74070 correct classification accuracy figure is not far above the base rate for the social phobics in this particular sample (70%), it is interesting to note that 75070 of the normal control group was also correctly classified, which is higher than their 30070 base rate in this particular sample. Thus, the scale appears to be both sensitive and specific. These data, combined with the results of our prior investigation (Turner et al., 1989), suggest that the SPAI is capable of discriminating social phobics from normal controls and from individuals with other types of anxiety disorders. With respect to the mis-classifications, 14 out of 20 (70%) were due to individuals who were diagnosed as socially phobic but who nonetheless had low scores on the inventory. These individuals appeared to have severe, yet specific and circumscribed social fears, mainly public speaking anxiety. Although social phobics with a fear of only one social situation may be the exception (Turner et al., 1986), they do account for a small percentage of the entire social phobic population. It is likely that such individuals will score in the severe range on only a small number of items, resulting in an overall low score in comparison to social phobics with pervasive disturbances. Therefore, when the SPAI is used as a screening instrument, it would be important to review carefully the responses to individual items rather than to rely strictly on the total score. The results of the first validity study also indicated that both social phobic and non-social phobic males scored higher on the inventory than their female counterparts. The higher scores by male subjects on this inventory is consistent with the scoring distribution of the SAD, but is inconsistent with the FNE (Watson & Friend, 1969), where females have a higher mean score. The reason for the inconsistency with the FNE is unclear. However, data from other investigations also support the conclusion that socially anxious and social phobic males may possess a more severe impairment than females. For example, socially anxious males were judged to have significantly poorer eye contact than socially anxious females or non-socially anxious males and females (Beidel, Turner, & Dancu, 1985).

VALIDITY OF THE SPAI

425

Social phobics had higher scores than normal controls on the agoraphobia subscale. There are several reasons which may explain this finding. First, in this investigation, the scores of a phobic sample (albeit from a student group who had not sought treatment but who nonetheless met DSM-III criteria for social phobia) were compared with normal controls. Based on the mere presence of a disorder, it is likely that a patient group would score higher on any measure of psychopathology. Additionally, the clinical picture of social phobia is often complicated by a high degree of general anxiety. For example, Sanderson, Rapee, & Barlow (1987) reported that 59°7o of their patients with a primary diagnosis of Generalized Anxiety Disorder also met criteria for social phobia. Given the existence of a pervasive anxiety disturbance, these individuals should endorse some degree of anxiety across many different settings. Thus, it is reasonable that social phobics would score higher than normals on the agoraphobia subscale. The social phobics' scores, although higher than normals, are much lower than those of an agoraphobic group (Turner et al., 1989). The results of the second concurrent validity study indicate that scores on the SPAI have some relationship to distress in daily social encounters. There was a moderate and significant correlation between the subjects' total SPAI score and daily ratings of distress when they were actually engaged in social encounters. Several other correlations (degree of distress from cognitions and entry into socially distressing situations) also attained statistical significance, and indicated a modest relationship with the SPAI. Correlations between the SPAI and the frequency of disturbing thoughts or avoidance of social situations were quite low, and did not reach statistical significance. The correlation coefficients may have been smaller than expected for several reasons. First, there is the issue of method variance. Ratings of the same construct achieved through two different methods might well result in only modest correlations. Second, scatterplots for several of the self-monitoring categories revealed the existence of an attenuated range, and even though many of the subjects in Study 2 met DSM-III criteria for social phobia (37O70), their monitoring data did reveal differences from those of patients who seek treatment in our Anxiety Disorders Clinic. For example, there were fewer incidents of avoidance of social situations in the study sample. In addition, the degree of distress reported by these participants, both as a result of disturbing thoughts or entry into social situations, was lower than that reported by our clinic patients. Further, in a previous report, the SPAI scores of this student group were somewhat lower than those of a clinic sample (Turner et al., 1989). Despite the apparent mild severity of social phobia evinced by subjects in this study, the clinical nature of this population cannot be discounted. First, as has been demonstrated previously, when asked to give an impromptu speech, subjects chosen through this type of screening procedure manifested autonomic reactions and reported negative cognitions which were similar to those of a clinic sample seeking treatment for social phobia (Turner, Beidel, & I arkin, 1986). Second, 57 subjects out of the total sample did meet DSM-III criteria for social phobia. However, inasmuch as none of these subjects had sought treatment for their social fears, it is likely that their disorder was not as severe

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as a clinic sample. Therefore, the restricted range of ratings on the selfmonitoring data might reflect the less severe quality o f this particular sample. Before reaching a final conclusion about the utility o f the SPAI in predicting daily social behaviors, we plan to replicate Study 2 using a clinic sample that is seeking treatment. With the exception o f general ratings o f social distress, the correlation coefficients for the SPAI and the self-monitoring data were o f a higher magnitude than those achieved using the SAD or the FNE, although they were not statistically significantly different. In addition, several o f the correlations between the SPAI and the diary data were statistically significant, yet the same correlations between the SAD and FNE were not. It should be pointed out that the SAD and the FNE were developed prior to the introduction o f the diagnostic criteria for social phobia, whereas the SPAI was developed specifically for the purpose o f assessing social phobia. Although the SAD and the FNE were not developed as clinical instruments and do not discriminate social phobics from individuals with other anxiety disorders (Turner, McCanna, & Beidel, 1987), they are sensitive to general distress. Thus, it might not be reasonable to expect significant differences between the SPAI and the FNE and SAD when used in this fashion. Also, differences between these measures may be increased when a patient sample is used. The results o f the external validity study (Study 3) indicate that there is a moderate degree o f correlation between the subject's own ratings of social distress and ratings made by a significant other. There are a number o f reasons that probably make it unrealistic to expect a higher overall correlation between the subject's ratings and that o f a significant other. First, many o f the components o f social phobia consist of internal events not readily observable to others (e.g., cognitions and somatic sensations). Second, one o f the critical characteristics o f social phobics is fear that others will detect their distress. Thus, they often go to great lengths to hide evidence o f their anxiety. Third, the behavioral manifestations o f social phobia are reticence, withdrawal, or isolation, rather than attention-getting acting out behaviors. Thus, in many instances even the overt signs are likely to go unnoticed. Under this set o f constraints, the correlations obtained in the external validity study are encouraging. It is also interesting to note that the correlation for the females tended to be higher than for the males or for the group as a whole. This is consistent with socio-culture explanations which suggest that women are more likely than men to express their fears overtly. The SPAI is a new instrument for the assessment o f social phobia. It was derived empirically, and its construction was based on the behavior-analytic procedures suggested by Goldfried and D'Zurilla (1969). The SPAI uses a Likert scale format to allow assessment o f symptom severity; determines social distress across a range o f potentially fear-producing situations; and taps indicators o f cognitive, somatic and behavioral distress. The SPAI has high testretest reliability and good internal consistency. The results o f this investigation indicate that the SPAI has adequate concurrent and external validity. Additional studies addressing the factor structure and the utility o f this scale to reflect improvement as a result of clinical intervention are currently underway.

VAI IDITY OF THE SPAI

427

REFERENCES American Psychiatric Association (1980). Diagnostic and statistical manual of mental disorders. (Third Edition). Washington, D.C,: American Psychiatric Association. American Psychiatric Association (1987). Diagnostic and statistical manual of mental disorders. (Third edition-revised). Washington, D.C.: American Psychiatric Association. Beidel, D. C., TUrner, S. M., & Dancu, C. V. (1985). Physiological, cognitive, and behavioral aspects of social anxiety. Behaviour Research and Therapy, 23, 109-117. DiNardo, P. A., O'Brien, G. T., Barlow, D. H., WaddeU, M. T., & Blanchard, E. B. (1983). Reliability of DSM-III anxiety disorder categories using a new structured interview. Archives of General Psychiatry, 40, 1070-1074. Goldfried, M. R., & D'Zurilla, T. J. (1969). A behavioral-analytic model for assessing competence. In C. D. Spidberger (Ed.), Current topics in chnicalpsychology (Volume h pp. 151-196). New York: Academic Press. Sanderson, W. C., Rapee, R. M., & Barlow D. H. (1987). The DSM-III-R revised anxiety disorder" categories: Descriptions and patterns of comorbldity. Paper presented at the Annual Meeting of the Association for Advancement of Behavior Therapy, Boston, MA. Spielberger, C. D., Gorsuch, R. L., & Lushene, R. E. (1970). The state-trazt anxiety inventory: Test manual for form X. Palo Alto, CA: Consulting Psychologists Press. Spielberger, C. D., Pollans, C. H., & Worden, T. J. (1984). Anxiety Disorders. In S. M. TUrner, & M. Hersen (Eds.), Adult psychopathology and diagnosis (pp. 263-303). New York: John Wiley and Sons. TUrner, S. M., & Beidel, D. C. (1989). Social phobia: Clinical syndrome, diagnosis and comorbidity. Climcai Psychology Review, 9, 3-18 Turner, S. M., Beidel, D, C., Dancu, C. V., & Stanley, M. A. (1989). An empirically derived inventory to measure social fears and anxiety: The Social Phobia and Anxiety Inventory. Psychological Assessment: A Journal of Consultmg and Clinical Psychology, 1, 35-40. TUrner, S. M., Beidel, D. C., Dancu, C. V., & Keys, D. (1986). Psychopathology of social phobia and its relationship to avoidant personality disorder. Journal of Abnormal Psychology, 95, 389-394. Turner, S. M., Beidel, D. C., & Larkin, K. T. (1986). Situational determinants of social anxiety in clinic and non-clinic samples: Physiological and cognitive correlates. Journal of Consuiting and Clinical Psychology, 54, 523-527. TUrner, S. M., McCanna, M., & Beidel, D. C. (1987). Discriminative validity of the Social Avoidance and Distress Scale and the Fear of Negative Evaluation Scale. Behaviour Research and Therapy, 25, 113-115. Watson, D., & Friend, R. (1969). Measurement of social-evaluative anxiety. Journal of Consulting and Clinical Psychology, 33, 448-457. R~CEIVED: August 29, 1988 F~ ACCEPT^NC~:October 28, 1988