Annotated Bibliograghy

Changes in delusions in the early phase of antipsychotic treatment – An experience sampling study

Suzanne Ho-wai So a,n, Emmanuelle Roisin Peters b,c, Joel Swendsen d,e, Philippa Anne Garety b,c,1, Shitij Kapur c,f,g,1

a Department of Psychology, The Chinese University of Hong Kong, Hong Kong SAR, China b Department of Psychology, King0s College London, Institute of Psychiatry, London, United Kingdom c National Institute for Health Research (NIHR) Biomedical Research Centre for Mental Health at South London and Maudsley NHS Foundation Trust and King’s College London, United Kingdom d University of Bordeaux, National Center for Scientific Research, Bordeaux, France e EPHE-La Sorbonne, Paris, France f Section on Schizophrenia, Imaging and Therapeutics, King’s College London, Institute of Psychiatry, London, United Kingdom g Department of Psychological Medicine, King’s College London, Institute of Psychiatry, London, United Kingdom

a r t i c l e i n f o

Article history: Received 6 September 2013 Received in revised form 4 December 2013 Accepted 16 December 2013 Available online 24 December 2013

a b s t r a c t

It has been suggested that different aspects of delusions (conviction, distress, preoccupation) respond to treatment at different rates, and that the cognitive bias of ‘Jumping to Conclusions’ (JTC) may predict treatment outcome. This study investigates changes in delusion dimensions using Experience Sampling Methodology (ESM) and the role of JTC as a predictor of change during the initial 2 weeks of antipsychotic treatment on admission to hospital. Sixteen acute patients with delusions were assessed seven times per day for 14 days using computerised ESM. ESM assessed moment-by-moment experiences of affect, psychotic symptoms, and delusion dimensions. Clinical ratings were completed at baseline, 1 week and 2 weeks later. The 0beads0 task was used to measure JTC at baseline. Delusion dimensions improved over the two weeks of antipsychotic treatment and admission to hospital. Different delusional dimensions changed at different rates, with distress and disruption being more responsive than conviction and preoccupation on both PSYRATS and ESM ratings. Eight out of 16 participants showed a JTC bias on the beads task at baseline. Exploratory analyses showed that JTC predicted changes in the ESM ratings of delusion conviction and distress, suggesting that reasoning biases may predict treatment response.

& 2013 Elsevier Ireland Ltd. All rights reserved.

1. Introduction

Factor analyses have shown that the delusional experience consists of a number of dimensions, with the majority of studies identifying conviction, distress, preoccupation and disruption to life (Kendler et al., 1983; Garety and Hemsley, 1987; Appelbaum et al., 1999; Peters et al., 2004; Lincoln, 2007). It has been suggested that these dimensions respond to cognitive therapy differently (Brett-Jones et al., 1987; Chadwick and Lowe, 1990, 1994). However, less is known about how they respond to antipsychotics. Jørgensen (1995) assessed changes in delusion dimensions in 50 patients with schizophrenia for 8 weeks after

readmission. Conviction, extension (i.e. the areas of life affected by the delusional belief) and pressure (i.e. the degree to which one is preoccupied with the delusional belief) were found to be distinctly independent dimensions of delusions. Seventy per cent of the patients showed partial remission of delusional beliefs, whereby reduction in pressure preceded improvement in conviction. Jørgensen (1995) focused on changes after readmission, and the effect of antipsychotics was not specifically examined. Mizrahi et al. (2006) assessed dimensions of the principal psychotic experience with 17 patients during the first 10 weeks of anti- psychotic treatment. They reported that behavioural impact and cognitive and emotional preoccupation changed more markedly and rapidly than conviction. The measures in these studies were not commonly used, and the dimensions measured were not the same as those generated in factor analysis studies. Nevertheless, these studies suggest a differential response of delusion dimen- sions to treatment, with conviction being less amenable to change than distress and preoccupation. This observation is consistent with patients’ reports that antipsychotics ‘detach’ them from their

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n Correspondence to: Room 321 Wong Foo Yuan Building, Department of Psychology, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong Special Administrative Region, China. Tel.: þ852 39436211; fax: þ852 26035019.

E-mail address: [email protected] (S.-w. So). 1 Joint last authors.

Psychiatry Research 215 (2014) 568–573

psychotic symptoms rather than eradicate or eliminate the symp- toms (Mizrahi et al., 2005).

These findings raise the question of why conviction persists while other dimensions improve, and what might predict change in conviction. It has been suggested (Garety et al., 2001; 2007) that the way patients form appraisals of experience may be charac- terised by reasoning biases, including ‘Jumping to Conclusions’ (JTC) bias and lack of belief flexibility, which may contribute to the development and maintenance of delusions. The JTC bias refers to the tendency to reach a decision without gathering sufficient data (Garety et al., 1991; Garety and Freeman, 1999). JTC occurs in one half to two-thirds of individuals with delusions (see reviews by Fine et al., 2007; Freeman, 2007), as well as in people scoring highly on delusional ideation scales (e.g. Linney et al., 1998; Colbert and Peters, 2002; Moritz and Woodward, 2005; Van Dael et al., 2006; Warman and Martin, 2006) and in people who have remitted from delusions (Moritz and Woodward, 2005; Peters and Garety, 2006). In some studies, JTC has also been found to be associated with severity of delusions and delusional conviction (Garety et al., 2005; Peters and Garety, 2006). JTC may therefore be a stable predisposing factor for delusions (see review by So et al., 2010).

Menon et al. (2008) found that JTC at baseline predicted subsequent change in psychotic symptoms during the initial weeks of antipsychotic treatment, and argued that JTC was a moderator of treatment outcome. However, they measured delu- sions using clinical ratings and did not measure delusion dimen- sions. Treatments targeting reasoning biases (including JTC) have recently been developed, with preliminary evidence showing a reduction in both JTC and delusion conviction (Waller et al., 2011) and distress (Moritz et al., 2011). Therefore, dimensions of delu- sions are important indicators of treatment outcomes.

There is evidence that, like other psychotic symptoms, delu- sions improve most markedly in the early weeks of antipsychotic treatment, and that initial change predicts overall symptom improvement (Agid et al., 2003; Leucht et al., 2005). Agid et al. (2003) even found that improvement in psychotic symptoms may be seen in the very first few hours. Mizrahi et al. (2006) found that the different pattern of improvement in delusional dimensions was evident as early as 2 weeks after the start of treatment. Therefore, the very early stage of treatment is a critical period for the fine-grained analysis of delusion change and is a good test bed for the moderators and mediators of such change.

Experience Sampling Methodology (ESM), a structured diary technique, has been shown to be a well-suited method for assessing moment-to-moment levels and fluctuations of psychotic experiences (e.g. Myin-Germeys et al., 2001; Peters et al., 2012). So et al. (2013) recently showed that ESM assessment using a Personal Digital Assistant (PDA) is feasible and valid during the acute psychotic stage of psychosis. The present study uses this approach to investigate changes in delusion dimensions during the initial 2 weeks of antipsychotic treatment. It was hypothesised that delusion distress and preoccupation, but not conviction, would reduce significantly over 2 weeks of antipsychotic treat- ment. This study also aimed to explore the potential role of the JTC bias in predicting delusion change. It was predicted that there would be an association between JTC bias at baseline and change in delusion dimensions over time.

2. Methods

2.1. Participants

Ethical approval for the study was granted by the South East London Research Ethics Committee 4 (ref. 10/H0807/44). In-patients with delusions (scoring 4 or above on at least one of the PANSS delusion items) and a clinical diagnosis (based

on clinical notes) of schizophrenia spectrum disorder or bipolar disorder were recruited. Patients were recruited and assessed as soon as they were admitted to the hospital for an acute psychotic episode, and no longer than 2 weeks after the start of antipsychotic treatment for the current episode. Patients with drug-induced psychosis or organic psychosis, and patients with a primary diagnosis of substance misuse were excluded.

2.2. Measures

2.2.1. Experience sampling assessment Participants were asked to complete self-assessment questionnaires on a

Personal Digital Assistant (PDA) seven times a day on 14 consecutive days. Each questionnaire consists of the same set of 20 items on affect, psychotic symptoms, delusion dimensions, and current environment. Details of the methodology and its validity are reported in greater detail in a separate paper (So et al., 2013).

There were four items on delusion dimensions in the ESM questionnaire. The questions were preceded with the statement: “The following questions concern the problem discussed with your researcher, in particular the thought or idea that…” followed by the exact wording of the ‘problem or main concern’ as described by the participant. The wording of the dimensions was similar to that used in Peters et al. (2012) – conviction (“At this moment, to what extent do you believe this concern is true?”), distress (“At this moment, how much does this concern upset you?”), preoccupation (“At this moment, to what extent does this concern go round and round in your mind?”), disruption (“At this moment, to what extent does this concern interfere with what you are doing?”). Participants were asked to rate the same delusional belief throughout the study period, on a 7-point Likert scale (from 1, ‘not at all’, to 7, ‘very much’).

2.2.2. Symptomatology and delusion dimensions In addition to ESM, psychotic symptoms at baseline and 2 weeks were

measured using three well-validated symptom scales. The Positive and Negative Syndrome Scale (PANSS; Kay et al., 1987) consists of a 7-item positive symptom scale, a 7-item negative symptom scale, a 16-item general psychopathology scale, and a total score. Each symptom is rated on a 1–7 scale, with the total score ranging from 30 to 210. The Schedule for the Assessment of Positive Symptoms (SAPS; Andreasen, 1984) is a 35-item interview-based scale covering 32 positive symp- toms of schizophrenia, organised into four areas (hallucinations, delusions, bizarre behaviour and positive formal thought disorder). Each area includes ratings of specific symptoms and a global rating (0–5), and total scores range from 0 to 175. The Psychotic Symptom Rating Scales (PSYRATS; Haddock et al., 1999) consists of an 11-item auditory hallucinations scale and a 6-item delusions scale, measuring multiple dimensions of the psychotic symptoms. The delusions scale of PSYRATS assesses four dimensions (conviction, amount and intensity of distress, amount and duration of preoccupation, and disruption to life). Items are rated by the interviewer on a 0–4 ordinal scale. In the present study, ratings of the two distress items and the two preoccupation items were averaged, yielding a distress score and a preoccupation score respectively.

The inclusion of three symptom scales constitutes a comprehensive assessment of symptom change. While PANSS provides overall scores for positive, negative and general symptoms, SAPS is a more detailed measure of positive symptoms and dimensional ratings of delusions are unique to PSYRATS.

2.2.3. Jumping to conclusions reasoning bias The beads task was designed to examine individuals’ data-gathering reasoning

style (Phillips and Edwards, 1966; Garety et al., 1991). In the beads task, individuals are presented with two jars, each containing 100 coloured beads. One jar contains 60 beads of one colour (e.g. black) and 40 beads of another (e.g. yellow), while the other jar contains beads in opposite proportions (i.e. 40 black and 60 yellow; Dudley et al., 1997). The jars are then removed from view. Upon request from the participant, beads are presented, one at a time, from one of the jars in a seemingly random (but in fact predetermined) order. All the beads drawn are replaced so the proportions of the coloured beads stay the same. Participants can view as many beads as they want until they decide with certainty from which jar the beads are drawn. The key variable is the number of beads requested before making a decision, with two beads or fewer classified as a ‘jumping to conclusions’ bias (Garety et al., 2005). The beads task was presented on a laptop computer at the baseline interview.

2.3. Procedures

All the clinical rating scales were administered by the first author, a clinical psychologist trained by experts in the use of these instruments. At the baseline interview, clinical rating scales were completed. The researcher agreed with the participant on the index delusional belief and programmed the individualised questionnaire onto a Palm Tungsten E2 PDA (Palm OSs version 5.2.1). Participants were given the PDA to carry with them and the ESM assessments began immediately. The PDA was programmed to emit a beep signal at seven random moments during the day, and participants were asked to respond to the signals as

S.H.-w. So et al. / Psychiatry Research 215 (2014) 568–573 569

soon as possible. In order to facilitate compliance with the procedure, the researcher contacted the participant at least twice in the first week to offer support. Individuals who demonstrated difficulty in understanding assessment questions or operating the device were given additional training.

2.4. Statistical analysis

Statistical analysis for this study involved clinical data at two time points and ESM data across 14 days, capturing both within- and between-individual differ- ences. The maximum number of potential signals a participant would receive was 98 (seven signals per day for 14 days). Only participants who completed at least 30 experience sampling activations are included in the analyses.

The ESM data sets contain repeated observations nested within participants. Since observations from the same individual are more similar than observations from different individuals, the residuals are not independent. Therefore, long- itudinal relationships of variables across levels (day and person) were evaluated using multilevel linear regression modelling (Goldstein, 1987; Snijders and Bosker, 1999), which is a standard method for analysing ESM data (Kimhy et al., 2012). All responses were considered in all regression analyses reported. Regression models were tested using the multilevel XTREG command in STATA 12 (StataCorp, 2012). Whenever mean levels of ESM scores are presented (e.g. in graphs), scores were calculated for each participant and then averaged.

The first set of multilevel modelling analysis aimed to investigate the main hypothesis relating to changes in psychotic symptoms and delusion dimensions over time. Separate regression models were estimated with each of the symptoms/ dimensions as Dependent Variables (DV) respectively and day as an Independent Variable (IV). For the secondary, exploratory hypothesis relating to the potential moderating effect of JTC on outcome, participants were grouped on the basis of their performance on the beads task. To test the effect of baseline JTC on changes in delusion dimensions over time, separate multilevel linear regression models were estimated with JTC, day, and JTC � day interaction as IVs, and the level of each delusion dimension (ESM ratings) as DV respectively.

Unilevel analyses of clinical ratings were performed on the IBM SPSS Statistics for Windows, Version 19.0 (IBM Corp. Released (2010)). Group differences in the level and changes in delusions were tested using Mann–Whitney U tests and within-person changes were tested using paired-sample t-tests.

3. Results

3.1. Demographic and clinical data

A total of 26 patients consented to participate in this study, among whom 16 completed at least 30 experience sampling assessments. The mean number of entries per participant was 59 (range 34–89). The mean rate of compliance was 70.7% (range 40.2–94.6%). The total number of observations available for multi- level models was 1306. There was no significant difference between the 16 participants who met the minimum compliance requirement and the ten participants who did not in age, duration and dosage of medication, number of admissions, or any of the clinical rating scores (p40.10).

Among the 16 completers, nine (56.25%) were male and seven (43.75%) were female. Mean age was 36.1 years (range 20–63 years). Psychiatric diagnoses from the case notes were available for 15 patients as follows: schizophrenia (n¼5), unspecified psychosis (n¼5), mood disorder with psychotic symptoms (n¼2), schizoaf- fective disorder (n¼1), delusional disorder (n¼1), and acute and transient psychotic disorder (n¼1). The average number of admis- sions (including the current one) was 1.73 (S.D.¼1.31; range 1–6). Eleven patients (68.8%) were in their first episode of psychosis. The average number of days on antipsychotics at the time of the first assessment was 4.56 (S.D.¼2.45; range 0–8). The average baseline rating of delusion on the SAPS was four (S.D.¼0.52), indicating a moderate to marked level of severity (Andreasen, 1984). Medica- tion types were as follows: 15 received atypical antipsychotics (Risperidone, Olanzapine, Aripiprazole, Quetiapine, Amisulpiride, and Clozapine), while one received a typical antipsychotic (Piportil). The mean starting dose of antipsychotics in chlorpromazine equiva- lents (Andreasen et al., 2010) was 131.86 mg/d (S.D.¼94.94).

Pattern of extreme responding was checked using ESM ratings of the key variables (i.e. delusion dimensions). Percentage of

extreme responses (a score of 1 or 7 on a 7-point scale) over 14 days was not significantly correlated with age (p¼0.54). However, female participants endorsed a significantly higher percentage of extreme responses on all four delusion dimensions compared to male participants (po0.01). Three (out of 16) participants had extreme responses (either 1 or 7 on the 7-point scale) for all prompts across 14 days on any of the key variables (i.e. delusion dimensions). However, all three participants made varied responses on other variables. Therefore, we did not exclude data of any participant due to extreme responding. As a standard procedure to control for potential confounds, all analyses adjusted for the effects of age and gender (e.g. Swendsen et al., 2011).

3.2. Jumping to conclusions (JTC) at baseline

Fourteen participants completed the beads task with a mean number of draws to decision of 5 (range 1–20). Eight participants (57.1%) showed the JTC bias. There was no significant difference at baseline between the JTC (n¼8) and no-JTC (n¼6) groups on PANSS scale scores, SAPS delusion score, or PSYRATS delusion and conviction scores (see Table 1 for means and S.D.s).

3.3. Changes in psychotic symptoms over 2 weeks

As shown in Table 2, there was a significant improvement in PANSS positive, general and total scores between baseline and

Table 1 Mean levels (S.D.) of symptom ratings at baseline in the JTC and no-JTC groups.

JTC group (n¼8)

No-JTC group (n¼6)

Mann–Whitney U

PANSS positive 22.50 (4.87) 18.83 (2.93) U¼36.00, p¼0.14

PANSS negative 12.75 (5.42) 12.33 (5.50) U¼24.50, p¼1.00

PANSS general 31.38 (11.05) 35.67 (11.20) U¼17.50, p¼0.41

PANSS total 66.63 (17.80) 66.83 (15.99) U¼23.50, p¼0.95

SAPS delusions 4.13 (0.35) 4.00 (0.63) U¼26.50, p¼0.76

PSYRATS delusions 18.63 (2.97) 15.17 (5.00) U¼32.00, p¼0.35

PSYRATS conviction 3.38 (0.52) 3.33 (0.82) U¼23.50, p¼0.95

PSYRATS distress 3.56 (0.42) 2.17 (1.69) U¼34.50, p¼0.18

PSYRATS preoccupation

2.50 (0.96) 2.08 (1.07) U¼31.50, p¼0.35

PSYRATS disruption 3.13 (0.64) 3.33 (0.52) U¼20.00, p¼0.66

Table 2 Mean levels (S.D.) of symptom ratings at baseline and week 2 (N¼16).

Baseline Week 2 Paired-sample t-test

PANSS positive 20.63 (4.52) 16.25 (3.72) t¼4.01, po0.01 PANSS negative 11.88 (5.24) 10.00 (3.58) t¼1.57, p¼0.17 PANSS general 33.25 (10.51) 24.75 (5.16) t¼3.78, po0.01 PANSS total 65.75 (16.10) 51.00 (10.91) t¼4.06, po0.01 SAPS delusions 4.00 (0.52) 3.13 (1.15) t¼3.22, po0.01 PSYRATS delusions 17.25 (3.92) 13.69 (3.63) t¼3.20, po0.01 PSYRATS conviction 3.38 (0.62) 3.25 (1.07) t¼0.46, p¼0.65 PSYRATS distress 3.03 (1.24) 2.13 (1.38) t¼2.52, p¼0.02 PSYRATS preoccupation 2.31 (0.93) 1.91 (0.69) t¼1.71, p¼0.11 PSYRATS disruption 3.19 (0.54) 2.38 (1.03) t¼3.57, po0.01

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week 2, as well as in delusions as assessed on the SAPS and PSYRATS.

3.3.1. Delusional distress and preoccupation but not conviction will reduce significantly over 2 weeks of antipsychotic treatment

As shown in Table 2, paired-sample t-tests revealed a signifi- cant reduction in PSYRATS ratings of Distress and Disruption. Change in Conviction or Preoccupation was not significant.

Changes in ESM self-ratings of delusion dimensions are shown in Fig. 1. Multilevel linear regression models showed a significant decrease in Distress (B¼ �0.04, SE¼0.01, po0.01) and Disruption (B¼ �0.03, SE¼0.01, p¼0.01), but not in Conviction or Preoccupa- tion (p40.10). In order to examine whether reduction in delusional dimensions was more marked in the earlier days than in the subsequent days, models with a quadratic term for time (i.e. squared Day) were tested for each delusional dimension. The quadratic effect of time was not significant (p40.10), suggesting a linear decrease in distress and disruption across the first 14 days.

3.3.2. There will be an association between JTC bias at baseline and change in delusion dimensions over time

Changes in the ESM delusion dimensions by JTC groups are presented in Fig. 2. In the model with ESM conviction as DV, there was no main effect of JTC on conviction (B¼0.79, SE¼1.00, p¼0.43) or distress (B¼1.02, SE¼0.83, p¼0.22). However, there was a significant interaction between JTC and Day (B¼0.10, SE¼0.03, po0.001), indicating that conviction change over time was different between the two groups, with a decrease in convic- tion in the no-JTC group only (See Fig. 2a). The interaction between JTC and Day was also significant for distress (B¼0.06, SE¼0.03, p¼0.02), indicating that distress change over time was different between the groups, with apparently little change in distress in the JTC group and a small decrease in the no-JTC group (see Fig. 2b).

For preoccupation and disruption there was no significant interaction between JTC and Day (p40.10). When the interaction term was taken out of the models, there was a significant main effect of JTC on level of preoccupation (B¼1.97, SE¼0.91, p¼0.03), with higher preoccupation scores being found in the JTC group (see Fig. 2c). The main effect did not reach significance for disruption (p40.05; see Fig. 2d).

In summary, the no-JTC group were less preoccupied with their delusions overall, and showed a greater improvement in convic- tion and distress over time than the JTC group. JTC did not predict changes in levels of preoccupation and disruption.

4. Discussion

This study investigated changes over time in delusions among 16 inpatients as they began antipsychotic treatment on admission to hospital, as well as exploring the role of the ‘Jumping to Conclusions’ (JTC) bias in predicting delusion change. The main findings are that (i) distress and disruption, but not conviction and

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Fig. 2. Change over time in delusional dimensions by baseline JTC (N¼14).

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preoccupation, improved on PSYRATS and ESM; and (ii) the JTC bias predicted a difference in change over time in both conviction and distress measured by ESM.

Our sample, which consisted mostly of first-episode patients, showed a rapid improvement in clinical symptoms, with PANSS scores and delusion ratings reducing by more than 20% over 2 weeks. This result is consistent with the ‘early onset hypothesis’ of antipsychotic action (Agid et al., 2003; Leucht et al., 2005). When assessed multi-dimensionally, both PSYRATS and ESM showed that the improvement was in delusion distress and disruption, and not conviction and preoccupation. Although gra- phical representation of ESM ratings seemed to also indicate some decrease in conviction and preoccupation (Fig. 1), their lack of significance may have been due to their greater variability over time, while distress and disruption showed a steady (linear) decline. Although the lack of improvement in preoccupation was not expected, our finding is consistent with Mizrahi et al. (2006) that conviction does not change reliably in the early phase of antipsychotic treatment. Our finding is also consistent with the patients’ perspective that antipsychotics help them cope better with, or become less distressed by, their psychotic symptoms, rather than eliminate the symptoms (Mizrahi et al., 2005).

Symptom ratings and multi-dimensional ratings revealed a rather different picture of the process of recovery, whereby delusions were rated as reduced in severity (on the clinical scales) even though the strength of the belief (i.e. conviction) remained relatively unchanged on both clinical scales and ESM, suggesting that (i) clinical ratings were largely affected by the affective dimensions of delusions, and that (ii) multi-dimensional assess- ment of delusions provides additional and important information about recovery that is not represented in the usual clinical ratings.

The ESM data revealed an interesting relationship between JTC and delusion dimensions. Conviction and distress declined in the no-JTC group but not in the JTC group. Preoccupation ratings were higher overall in the JTC group, but JTC did not predict change in either preoccupation or disruption. These findings suggest that JTC is associated with introspection and rumination about one’s delusions, contributing to persistence of delusions, at least in terms of conviction and distress (Garety et al., 2005; Menon et al., 2008). While the relationship between JTC and conviction has been replicated and discussed in other studies (Garety et al., 2005; Fine et al., 2007), it is the first time that such a link was demonstrated using a moment-by-moment diary measure. Together with data from reasoning training studies (Moritz et al., 2011; Waller et al., 2011), our finding provides further evidence that the JTC data- gathering style is a moderator of treatment response of delusion dimensions. A recent study found evidence for a correspondence between change in JTC and change in delusions following cognitive behavioural therapy (Sanford et al., 2013). However, the current study measured JTC at baseline only and did not investigate the role of JTC as a mediator of treatment outcome.

There are several limitations to this study. Firstly, the sample size was adapted for analysis using the ESM data (assessed at multiple time points) but was underpowered for group compar- isons on JTC. It is therefore possible that the lack of interactions found on the preoccupation and disruption dimensions may have been due to a lack of power. However, the fact that significant findings were obtained for both conviction and distress despite the small sample size suggests that they are large effects, although it cannot be concluded that JTC is a moderator of these dimensions exclusively.

Secondly, patients were not sub-divided based on the type of antipsychotics they were taking, or their diagnosis. It is possible that medication or diagnosis may have been confounding vari- ables. Therefore, findings should be interpreted with caution and replication of the novel findings is needed.

Lastly, we cannot determine conclusively whether the changes that were captured are entirely due to a response to the pharma- cological intervention received by the patients. All participants were recruited at the start of a hospital admission, which offers a range of interventions from a multidisciplinary team. While it is unlikely that psychological interventions would have been offered, or made an impact, in the short time-span of the study, we cannot be clear on how much of the changes were a result of nursing or occupational therapy input, or just the removal from a stressful situation.

Despite these caveats, it is to our knowledge the first study to have measured the response of psychotic symptoms in the acute stage using ESM and provides confirmation that aspects of delu- sions improve within the first 2 weeks of admission to hospital, even when viewed from the patient’s experiential perspective, and provides new evidence that JTC may be a predictor of treatment response.

Acknowledgements

This work was supported by the Croucher Foundation Scholar- ship and the University of London Central Research Fund to SHS. SK receives Grant support from AstraZeneca, Bristol-Myers Squibb (BMS) and Glaxo Smith Kline. He is a consultant/speaker/advisor for the following companies: AstraZeneca, Bioline, Bristol Meyers Squibb, Eli Lilly, Janssen (Johnson and Johnson), Lundbeck, Otsuka, Organon, Pfizer, Servier, Solvay Wyeth. PG, SK and EP acknowledge support for some clinical sessions from the National Institute of Health Research (NIHR) Biomedical Research Centre for Mental Health at the South London and Maudsley NHS Foundation Trust and the Institute of Psychiatry, King’s College London.

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