ARE SOME TYPES OF PSYCHOTIC SYMPTOMS MORE RESPONSIVE TO COGNITIVE-BEHAVIOUR THERAPY?

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1 Behavioural and Cognitive Psychotherapy, 2001, 29, Cambridge University Press. Printed in the United Kingdom ARE SOME TYPES OF PSYCHOTIC SYMPTOMS MORE RESPONSIVE TO COGNITIVE-BEHAVIOUR THERAPY? Nicholas Tarrier, Caroline Kinney, Eilis McCarthy, Anja Wittkowski, Lawrence Yusupoff, Ann Gledhill University of Manchester, U.K. Julie Morris Withington Hospital, Manchester, U.K. Lloyd Humphreys University of Manchester, U.K. Abstract. Results are presented from a randomized controlled trial indicating which psychotic symptoms respond to cognitive behaviour therapy. The aim of the study was to investigate whether different types of psychotic symptoms are more or less responsive to cognitivebehaviour therapy compared to treatment received by control groups. Seventy-two patients suffering from chronic schizophrenia who experienced persistent positive psychotic symptoms were assessed at baseline and randomized to either cognitive-behaviour therapy and routine care, supportive counselling and routine care, or routine care alone and were reassessed after 3 months of treatment (post-treatment). Independent and blind assessment of outcome indicated delusions significantly improved with both cognitive behaviour therapy and supportive counselling compared to routine care. Hallucinations significantly decreased with cognitive-behaviour therapy compared to supportive counselling. There was no difference in the percentage change of hallucinations compared to delusions in patients treated by cognitive behaviour therapy. There was little change in measures of affective symptoms but there was no evidence that a reduction in positive symptoms was associated with an increase in depression. In fact, a reduction in positive symptoms was positively correlated with a reduction in depression. There were significant differences in the reductions in thought disorder and negative symptoms with an advantage of cognitive-behaviour therapy compared to routine care. Keywords: Cognitive-behaviour therapy, schizophrenia, psychotic symptoms, hallucinations, delusions. Reprint requests to Nick Tarrier, Department of Clinical Psychology, Research and Teaching Block, Withington Hospital, Manchester M20 8LR, U.K. ntarrier@fs1.with.man.ac.uk 2001 British Association for Behavioural and Cognitive Psychotherapies

2 46 N. Tarrier et al. Introduction Evidence for the efficacy of cognitive-behaviour therapy in treating chronic and drug resistant psychotic symptoms in schizophrenia has progressed through case studies, case series and uncontrolled trials (see Haddock et al., 1998 for a review), to small controlled trials (e.g., Tarrier et al., 1993; Garety, Kuipers, Fowler, Chamberlain, & Dunn, 1994; Bentall, Haddock, & Slade, 1994; Drury, Birchwood, Cochrane, & MacMillan, 1996) and large methodologically rigorous randomized controlled clinical trials (e.g., Kuipers et al., 1997; Tarrier et al., 1998; Sensky et al., 2000). These studies use a broad definition of medication resistance in that positive symptoms needed to be present and frequent (Bentall et al., 1994; Drury et al., 1996) or present for at least 6 months despite appropriate neuroleptic medication (Tarrier et al., 1993, 1998; Garety et al., 1994; Kuipers et al., 1997). The general finding has been that cognitive behaviour therapy appears to significantly decrease persistent positive psychotic symptoms, although improvements in affective and negative symptoms have been less certain. There has, therefore, been considerable optimism that cognitivebehaviour therapy offers a way forward to improving the management of schizophrenia (Kingdon, Turkington, & John, 1994; Haddock et al., 1998). Previous studies, including the initial report of this study (Tarrier et al., 1988), have tended to report on gross changes in symptomatology. Given that there is accumulating evidence that psychotic symptoms in general decrease with cognitive-behaviour therapy, it is of interest to investigate whether some types of symptoms are more responsive to this treatment approach than others. The purpose of this paper is to examine the treatment effects on different types of symptoms in chronic schizophrenic patients in more detail. This aim was carried out by investigating a number of different questions, formulated from the results of previous studies: 1) Was there a difference in treatment response between hallucinations and delusions? 2) Did affective symptoms respond to treatment? 3) Did a reduction in psychotic symptoms result in an increase in depression? 4) Did thought disorder respond to treatment? 5) Did negative symptoms respond to treatment? An earlier paper (Tarrier et al., 1998) gave an overview of the intention-to-treat analysis in which all randomized patients, including drop-outs, were included in the analysis. In this paper, reporting on the same study, we describe the results only from patients who were exposed to the full treatment programme, an analysis-toprotocol. This allows us to investigate the effect of receipt of the full treatment protocol of either cognitive-behaviour therapy or supportive counselling on various different types of symptoms. Procedure Method Patients were identified through screening hospital and community patient data bases in three National Health Service Trusts in Greater Manchester, UK which represented a geographic cohort from a catchment area of 508,049 (1994 census). The case notes of these patients were then screened and the responsible medical officer was approached to give permission for the assessment of those meeting the inclusion criteria at this stage. Patients were then approached to give informed consent and, if obtained, were interviewed to confirm entry criteria and provide baseline assessments. Patients had to fulfil the following criteria: a

3 Psychotic symptoms 47 diagnosis of schizophrenia, schizoaffective psychosis or delusional disorder using DSM-IIIR criteria (APA, 1987); no evidence of organic brain disease; substance abuse was not identified as the primary problem; aged between 18 and 65; suffering persistent hallucinations and/or delusions for a minimum of 6 months, and at least 1 month stabilization if they had suffered an exacerbation during this period (the persistence of symptoms despite appropriate medication was established through examination of the detailed case notes, verification from the clinical team responsible for the patients and from the patient s account); they were on stable medication; were not receiving psychological or family intervention; their responsible medical officer had given permission for them to enter the study; they did not pose a serious threat of violence towards the assessors; and they had given informed consent to participate. Patients so recruited were assessed on baseline measures. After assessment patients were allocated on a stratified block randomized procedure with block size equal to nine, using symptom severity (determined by a total Psychiatric Assessment Scale score (Krawieka, Goldberg, & Vaughan, 1977), of 12 or less (low severity) or 13 or more (high severity)) and gender, to one of three treatment groups: cognitive-behavioural therapy plus routine care; supportive counselling plus routine care; and routine care alone. Allocation, contained in sealed envelopes, was carried out independently by a third party. Treatment groups Intensive cognitive behaviour therapy plus routine care. This intervention consisted of three components: i) coping strategy enhancement: aimed at the reduction of positive symptoms; ii) problem solving: aimed at increasing the level of functioning of the patient; (iii) cognitive-behavioural relapse prevention strategies: aimed to reduce future relapse risk. The three treatment components each consisted of six hourly sessions that were finally followed by two summary sessions. Sessions were carried out twice a week and 20 sessions of treatment were carried out over 10 weeks. Coping Strategy Enhancement consisted of a cognitive-behavioural analysis of each of the patient s psychotic symptoms and their use of coping strategies by means of a semi-structured interview, the Antecedent and Coping Interview (Tarrier, 1992). Based on this assessment, the patient was systematically trained in an array of techniques to help them cope and reduce their symptoms. These included: distraction and attention control techniques; guided imagery; self-regulatory internal dialogue; identification and modification of cognitive biases and arbitrary inference; disconfirmation of erroneous beliefs through cognitive challenge and behavioural experiments; activity scheduling; social engagement; and stress management. Special emphasis was placed on belief modification and reality testing as methods of coping with, and challenging beliefs about, their psychotic symptoms. Problem solving consisted of: the generation of a problem list and wish to change list ; instruction in the general skills of problem solving through its application to abstract problems (e.g., simple games) and then standardized problems (e.g., how to make friends when moving to a new residential area); and then the application of the problem solving skill to specific areas of functioning identified and listed earlier by the patient. Emphasis was given to problems of relevance to the patient (usually areas of impaired functioning) and on the behavioural rehearsal of their solution. In relapse prevention, the patient was taught to identify the prodromal signs and symptoms, and environmental stressors associated with past relapse. Aspects of the patient s environment, including social and family environment, which might be a future source of stress were analysed. Using a prob-

4 48 N. Tarrier et al. lem solving framework, methods of coping with prodromal symptoms and stressful situations were generated and learnt by the patient so that they could be used in the future. Patients were encouraged to perform appropriate homework exercises between sessions and to use their acquired skills in real life situations. These treatment methods are detailed elsewhere (Tarrier, 1992, 2001). Supportive counselling plus routine care. This intervention aimed to provide emotional support through the development of a supportive relationship fostering rapport and unconditional regard for the patient. General counselling skills were used to maximize the nonspecific effects of intervention through developing a relationship with the patient, taking an interest in them and discussing their life circumstances. Supportive counselling followed an identical format to the cognitive-behaviour therapy intervention: 20 one-hour sessions twice a week. Routine care. Routine care consisted of the standard psychiatric management by the clinical team of medication and monitoring through outpatient follow-up and case management. Treatment fidelity Therapy was performed by three clinical psychologists, accredited cognitive-behavioural therapists, experienced in this intervention (NT, LY & AG), two of whom (NT & LY) had been involved in an earlier trial (Tarrier et al., 1993). Cognitive-behaviour therapy and Supportive Counselling interventions followed a protocol manual and were carried out by all three therapists who met on a regular basis for peer supervision. Treatment fidelity was assessed through blind and independent rating of 34 arbitrarily selected taped therapy sessions. The rater assessed the taped sessions to be either cognitive-behaviour therapy or supportive counselling. Sessions identified to be cognitive-behaviour therapy were further assessed as coping strategy enhancement, problem solving or relapse prevention. Correct classification was found on 33 of the 34 sessions, one early coping session was classified as borderline supportive counselling, thus achieving 97% accuracy (Tarrier et al., 1998). Assessments The assessment strategy was to use standardized and appropriate measures that focused on specific areas of psychopathology. Assessments were carried out at baseline prior to treatment and 3 months later (post-treatment). Basic demographic information and details of medication type and dosage during treatment were also collected. The accessors were unaware of the treatment allocation of the patient. This was achieved by using separate offices in a different part of the hospital for the assessors and therapists, using separate administrative procedures, providing instructions to the patient not to reveal details of their care, data entry being carried out independently of the assessors and by using a multiple coding system for treatment groups. After the completion of post-treatment assessments the assessors were asked to indicate which treatment they thought each patient had received. They were not given any prior warning that they would be asked to do this so as not to prime them to the task. Comparison of the assessors guesses and actual allocation found that guesses were not significantly better than chance. The following clinical assessments were performed:

5 Psychotic symptoms 49 1) Hallucinations and delusions: individual target symptoms were separately elicited by means of the Present State Examination (PSE, Wing, Cooper, & Sartorius, 1974) and individually rated on the Brief Psychiatric Rating Scale 7-point scale of severity (0 to 6) for hallucinations or unusual thought content (BPRS, Lukoff, Liberman, & Nuechterlein, 1986). This allowed a separate score of the severity of hallucinations or delusions experienced by each individual to be calculated. This was done by aggregating the scores on the 7-point scales for all the affirmed delusional and hallucination symptoms categories on the PSE schedule. This produced an individualized aggregate score of target symptoms (hallucinations and delusions) for each patient. 2) Negative symptoms: were assessed by use of the Scale for Assessment of Negative Symptoms (SANS, Andreasen, 1989) which consists of 5 sub-scales: alogia; affective flattening; avolition; anhedonia, and attention, each measured on a 6-point scale of severity (0 5). A total score was obtained by aggregating the sub-scales. 3) General psychopathology: was assessed by use of the KGV scale (sometimes known as the Psychiatric Assessment Scale, PAS or Manchester scale) (Krawieka et al., 1977), an instrument for assessing chronic psychotic patients, which consists of 8 sub-scales: anxiety; depression; hallucinations; delusions; incoherence of speech; poverty of speech; flat affect; and psychomotor retardation, each measured on a 5-points scale of severity (0 to 4). An overall measure of psychopathology in psychotic patients was obtained by aggregating all the scales into a total score. The incoherence of speech sub-scale was used as a measure of thought disorder. Depression and hopelessness were assessed by use of the Beck Depression Inventory (BDI, Beck, 1988) and Beck Hopelessness Scale (BHS, Beck & Steer, 1988), the latter is also an indirect measure of suicide risk. Results Sample Eighty-seven patients fulfilled entry criteria and completed pre-treatment assessment and were randomized. Fifteen patients were lost to the study, of these 12 refused to continue in the study, 2 died of natural causes and 1 left the area. This resulted in 72 patients completing the treatment programme, an allocation of: 24 in cognitive-behaviour therapy; 21 in supportive counselling; and 27 in routine care. This paper reports on the analysis of these 72 patients. The sample characteristics and baseline clinical data are presented in Table 1. There were no statistical or clinical differences between patients allocated to the three treatment groups at baseline. No significant differences were found between the three treatment groups over the trial period in terms of type or dose of medication. Nine patients were taking atypical neuroleptic drugs (clozapine and risperidone) during the duration of treatment (two in the cognitive behaviour therapy group, four in the supportive counselling group, and three in the routine care group). Of the 72 patients, 59 (82%) experienced delusions, 55 (76%) experienced hallucinations and 42 (58%) experienced both delusions and hallucinations. Data an analysis Results were analysed using SPSS for Windows (version 6.1) and in consultation with the Regional statistics unit at Withington Hospital. Non-parametric statistics were used because

6 50 N. Tarrier et al. Table 1. Characteristics of the patient sample at baseline (n = 72) by treatment group Cognitive Supportive behaviour Routine care counselling therapy Gender Male 24 (44%) 15 (28%) 15 (28%) Female 3 (17%) 6 (33%) 9 (50%) Age Mean (SD) (9.9) (10.28) (12.26) Severity, High (KGV total >12) 12 (41%) 7 (24%) 10 (35%) Low (KGV total <12) 15 (35%) 14 (33%) 14 (33%) Marital status Single 21 (41%) 17 (33%) 13 (26%) Married 3 (30%) 3 (30%) 4 (40%) Separated/divorced 2 (25%) 0 (0%) 6 (75%) Widowed 0 (0%) 0 (0%) 1 (100%) Cohabiting 1 (50%) 1 (50%) 0 (0%) Residential status Rented accommodation 19 (36%) 15 (28%) 19 (36%) Hostel 4 (57%) 2 (29%) 1 (14%) Parents 4 (33%) 4 (33%) 4 (33%) Who lives with patient Alone 6 (32%) 5 (26%) 8 (42%) Partner/children 6 (35%) 4 (24%) 7 (41%) Partner/siblings 9 (38%) 8 (33%) 7 (29%) Other residents 4 (40%) 4 (40%) 2 (20%) Friends/others 2 (100%) 0 (0%) 0 (0%) Age left education* Median (IQR) 16 (16 to 17) 16 (15 to 18) 16 (15.25 to 17.75) Employment Paid 2 (50%) 1 (25%) 1 (25%) Voluntary/full-time education/ work therapy 3 (60%) 2 (40%) 0 (0%) None 22 (35%) 18 (29%) 23 (37%) Occupation Professional 1 (17%) 2 (33%) 3 (50%) Skilled 1 (7%) 7 (50%) 6 (43%) Unskilled 25 (49%) 12 (24%) 14 (28%) Never 0 (0%) 0 (0%) 1 (100%) Duration of illness (years) Mean (SD) (8.31) (9.35) (11.67) Number of previous admissions Mean (SD) 6.48 (10.45) 4.48 (5.19) 4.04 (3.42) Forensic history Yes 3 (38%) 4 (50%) 1 (13%) No 24 (38%) 17 (27%) 23 (36%) Alcohol units consumed per day Mean (SD) 0.69 (1.04) 1.28 (1.69) 1.45 (2.29) Previous substance abuse problems (n) Yes 3 (30%) 1 (10%) 6 (60%) No 24 (39%) 20 (32%) 18 (29%) Medication cpz equivalent daily (mg) Median (IQR) (300 to 803.6) (321.8 to ) (204.4 to )

7 Psychotic symptoms 51 Table 1. Continued Baseline clinical measures* Cognitive Supportive behaviour Routine care counselling therapy median (IQR) median (IQR) median (IQR) Number of delusions (1 to 3) (1.5 to 5.5) (0.25 to 4.75) Delusion severity (4 to 17) (6 to 29) (1.25 to 19.75) Number of hallucinations (1 to 3) (0 to 2) (1 to 2.75) Hallucination severity (2 to 12) (0 to 10) (3 to 11.25) Co-morbid 1 number of delusions (3 to 4) (2 to 6.5) (2.5 to 7) Co-morbid 1 delusion severity (14 to 20.25) (9 to 33.5) (11 to 35) Co-morbid 1 number of hallucinations (2 to 3.75) (1 to 3) (1 to 4) Co-morbid 1 hallucination severity (5.25 to 14.5) (5.5 to 12) (5.5 to 14.5) SANS total (8 to 14) (7.5 to 16) (9.25 to 14) SANS subscales: Blunting 2 (1 to 3) 2 (1 to 3) 2 (1 to 3) Alogia 1 (0 to 3) 2 (0.5 to 3) 2 (0.25 to 3) Avolition 3 (2 to 4) 3 (1.5 to 4) 3 (3 to 4) Anhedonia 4 (3 to 4) 4 (2.5 to 4) 3 (2.25 to 4) Attention 1 (0 to 2) 2 (0.5 to 4) 2 (1 to 3) KGV total (10 to 15) (8 to 15) (8.25 to 14.75) KGV subscales: Depression 2 (1 to 3) 2 (0 to 2) 2 (1 to 2) Anxiety 2 (1 to 3) 1 (0 to 2) 1.5 (0.25 to 2.75) Delusions 3 (2 to 4) 3 (2 to 4) 3 (2.25 to 4) Hallucinations 3 (0 to 4) 3 (0 to 4) 2 (0.5 to 4) Flattened Incongruous 1 (1 to 2) 1 (0 to 2) 1 (0 to 2) Psychomotor retardation 0 (0 to 2) 1 (0 to 2) 1 (0 to 1.75) Incoherence of speech 0 (0 to 1) 0 (0 to 2) 0 (0 to 2) Poverty of speech 0 (0 to 1) 0 (0 to 1) 0 (0 to 1) *Non-normal distribution which cannot be transformed, therefore distribution free statistics reported on total sample (n = 72) 1 Those patients experiencing both hallucinations and delusions (n = 42) of the characteristics of the data. Tests of skewness and kurtosis for clinical outcome variables were not acceptable. No suitable transformation provided an adequate approximation to a Normal distribution. Since parametric analysis requires the assumption of Normality which was not valid in these data, non-parametric statistics were used to analyse the raw data. 1) Was there a difference in treatment response between hallucinations and delusions? To test this hypothesis, analyses were carried out on data from a sub-set of patients who

8 52 N. Tarrier et al. experienced both delusions and hallucinations (n = 42) at pre-treatment. This analysis was carried out so that changes in these two types of symptom could be compared within the same patient, so factors relating to the patient were held constant. First, comparisons were made between treatment groups on the percentage change of each symptom to examine whether there was a difference between treatment groups. Kruskal-Wallis ANOVA comparing change on the severity of hallucinations indicated that there was a significant difference in the relative change in symptoms and treatment group (chi 2 = 9.45, p =.009). Post-hoc comparisons, using Mann-Whitney test with Bonferroni correction, indicated that there was a significantly greater improvement in cognitive behaviour therapy compared to supportive counselling (z = 2.9, p =.012). Similar comparison group difference for the severity of delusions indicated a significant difference between treatments (chi 2 = 15.2, p =.001). Post hoc comparisons indicated significant difference between cognitive behaviour therapy and routine care (z = 0.6, p =.001) and a trend between supportive counselling and routine care (z = 2.33, p =.06). Second, separate comparisons within treatment groups were made on percentage change between the severity of delusions and hallucinations in these patients to investigate whether these two types of symptom responded differently to treatment. There was no significant difference within the cognitive behaviour therapy group between the percentage change of hallucinations and delusions (n = 13, hallucinations % decrease 54% (SD 37), effect size 1.2; delusions % decrease 49% (SD 38), effect size 1.0; Wilcoxon test z =.76, ns). There was a difference in direction within the supportive counselling group with hallucinations showing an increase over treatment and delusions a decrease but this was not significant (n = 13, hallucinations % increase 16% (SD 74), effect size.09; delusions % decrease 22% (SD 34), effect size 0.5, z = 1.33, ns). Although the variability within subjects is great there was an indication that both cognitive behaviour therapy and supportive counselling were superior to routine care in the treatment of delusions and that cognitive behaviour therapy was superior to supportive counselling in the treatment of hallucinations. There was no evidence that hallucinations responded differently to delusions when treated with cognitive behaviour therapy. 2) Did affective symptoms respond to treatment? The anxiety and depression scales of the KGV and the BDI and BHS self-report measure were examined to investigate whether affective symptoms improved over treatment and whether treatment groups differed at posttreatment or in their change. There were no significant effects on any of these measures either over treatment or between treatment groups. Thus there appears to be no advantage of cognitive-behaviour therapy on affective symptoms. 3) Did depression increase if positive symptoms were reduced? To test the hypothesis that patients whose positive symptoms were reduced became more depressed, the correlations between changes in measures of depression and the severity of positive symptoms were examined. Two self-report measures, the BDI as a general assessment of depression and the BHS as a specific measure of hopelessness and one rater measure, the depression scale of the KGV, were used. It would be predicted that if mood were adversely affected by alleviation of positive symptoms then there would be significant negative correlations between the change scores of positive symptoms and depression. The hypothesis was not supported. There were modest positive correlations between positive symptoms change and the measures of depression: KGV depression scale (rs =.31, p =.0008), the BHS (rs =.28,

9 Psychotic symptoms 53 p =.018) and BDI (rs =.25 p =.032) suggesting that improvements in positive symptoms were associated with improvement in mood. 4) Does thought disorder respond to treatment? This was investigated by examining the KGV sub-scale incoherence of speech, which reflects thought disorder. There were significant group differences on change scores (chi 2 = 7.24, p =.03). There was a significant difference between cognitive-behaviour therapy and routine care (Mann Whitney U-test, p =.013), with the routine care group showing either no change or some deterioration. 5) Did negative symptoms respond to treatment? The effect of treatment on negative symptoms was investigated by examination of treatment effects on the SANS score and its sub-scales. There was a significant difference in change scores with all groups showing some improvement (median change scores: cognitive behaviour therapy 2 (IQR 3.75 to 0), supportive counselling 1 ( 2.5 to 0), routine care 0 ( 1 to 0); chi 2 = 5.83, p >.05). Mann Whitney U-tests revealed a trend towards significantly greater improvement in cognitive-behaviour therapy compared to routine care (p =.07). Analysis of the change scores for the individual sub-scales indicated a significant difference for alogia (chi 2 = 6.48, p =.04) with a trend towards significance for a greater improvement for cognitive-behaviour therapy compared to supportive counselling for alogia (p =.06). There were no significant differences for the affective flattening, anhedonia, attention and avolition sub-scales or for the KGV negative symptoms sub-scales of flat affect, psychomotor retardation and poverty of speech. Discussion Both hallucinations and delusions appear to be treatable by cognitive behaviour therapy. When patients receive the full treatment programme there was no evidence that hallucinations respond less well to cognitive behaviour therapy than delusions. Cognitive-behaviour therapy appears to be superior than supportive counselling in improving hallucinations, although both do well with delusions. The absence of a treatment effect on affective symptoms was a disappointment and contrary to what was expected given the reduction in anxiety reported in our previous study (Tarrier et al., 1993). It was possible to make alternative predictions concerning the changes in depression, either that depression would improve with psychotic symptom improvement or, as was suggested by some anecdotal evidence from patient accounts from our previous study (Tarrier et al., 1993), symptom improvement may result in increased depression. The latter hypothesis was not supported and there was no evidence that reduction in psychotic symptoms resulted in increased depression. There were modest correlations between reduced psychotic symptoms and decreased depression, which were higher for the objective interviewer based measure of depression than the subjective self-rating measure. Previous cognitive-behaviour therapy studies have paid little attention to thought disorder, although Kingdon and Turkington (1994) describe anecdotally the treatment of thought disordered patients using cognitive-behaviour therapy. Thought disorder may be amenable to psychological treatments as Haddock, Wolfenden, Lowens, Tarrier and Bentall (1995) have demonstrated experimentally that thought disorder varied depending on the emotional salience of a probe conversation. Thus, the structure of the cognitive-behaviour therapy approach could well result in some improvements in patients suffering from mild to moder-

10 54 N. Tarrier et al. ate thought disorder. Our results lend support to this but must be interpreted cautiously as change on the incoherence of speech sub-scale of the KGV was the only measure that assessed thought disorder. Little comment can be made about severely thought disordered patients who most likely would have been ineligible for the study by being unable to give informed consent. Some significant improvements in negative symptoms in patients treated by cognitive-behaviour therapy is an encouraging finding although changes were not even across all negative symptoms and may be restricted to specific types of functioning. These results should be interpreted with some caution. The analyses reported here are exploratory and investigate sub-groups of the larger study, which may introduce bias. It was beyond the limits of the study to be able to control medication prescription or to standardize medication for the study patients. We were reliant on the clinical judgement of the clinical teams to prescribe optimal medication. Furthermore, we do not know if these results would have been different if atypical neuroleptics had been more widely available to the study patients. Lastly, assessments that measure various dimensions of hallucinations and delusions such as frequency, severity, preoccupation, were not used and it may well be that psychological treatments affect these dimensions differently. Acknowledgement The study was supported by a project grant from The Wellcome Trust. References American Psychiatric Association (1987). Diagnostic and statistical manual (3rd Ed. Revised). Washington, DC: American Psychiatric Association. Andreason, N. C. (1989). Scale for the assessment of negative symptoms (SANS). British Journal of Psychiatry, 155 (Suppl. 7), Beck, A.T. (1988). Beck depression inventory, manual. San Antonio: The Psychological Corporation. Beck, A. T., & Steer, R. A. (1988). Beck hopelessness scale, manual. San Antonio: The Psychological Corporation. Bentall, R. P., Haddock, G., & Slade, P. D. (1994). Cognitive behavior therapy for persistent auditory hallucinations: From theory to therapy. Behavior Therapy, 25, Drury, V., Birchwood, M., Cochrane, R.,& MacMillan, F. (1996). Cognitive therapy and recovery from acute psychosis. I: Impact on symptoms. British Journal of Psychiatry, 169, Garety, P. A., Kuipers, L., Fowler, D., Chamberlain, F., & Dunn, G. (1994). Cognitivebehaviour therapy for drug resistant psychosis. British Journal of Medical Psychology, 67, Haddock, G., Wolfenden, M., Lowens, I., Tarrier, N., & Bentall, R. P. (1995). The effect of emotional salience on the thought disorder of patients with a diagnosis of schizophrenia. British Journal of Psychiatry, 167, Haddock, G., Tarrier, N., Spaulding, W., Yusupoff, L., Kinney, C., & McCarthy, E. (1998). Individual cognitive-behavior therapy in the treatment of hallucinations and delusions: A review. Clinical Psychology Review, 18, Kingdon, D., & Turkington, D. (1994). Cognitive behaviour therapy of schizophrenia. New York: Guilford Press. Kingdon, D., Turkington, D., & John, C. (1994). Cognitive-behaviour therapy of schizophrenia: The amenability of delusions and hallucinations to reasoning. British Journal of Psychiatry, 164,

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