Danger ideation reduction therapy (DIRT) for obsessive± compulsive washers. A controlled trial

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1 PERGAMON Behaviour Research and Therapy 36 (1998) 959±970 BEHAVIOUR RESEARCH AND THERAPY Danger ideation reduction therapy (DIRT) for obsessive± compulsive washers. A controlled trial Mairwen K. Jones *, Ross G. Menzies Department of Behavioural Sciences, Faculty of Health Sciences, The University of Sydney, P.O. Box 170, Lidcombe, NSW 2141, Australia Abstract Twenty-one OCD su erers with washing/contamination concerns took part in a controlled treatment trial at the Anxiety Disorders Clinic, University of Sydney. Eleven of the subjects received danger ideation reduction therapy (DIRT) over eight, 1 h weekly group sessions conducted by the second author. Ten subjects were placed on a wait list and did not receive DIRT or any other treatment. DIRT procedures were solely directed at decreasing danger-related expectancies concerning contamination and did not include exposure, response prevention or behavioural experiments. Components of DIRT include attentional focusing, lmed interviews, corrective information, cognitive restructuring, expert testimony, microbiological experiments and a probability of catastrophe assessment task. All subjects were assessed at pre-treatment, post-treatment and three-month follow-up using the Maudsley Obsessional±Compulsive Inventory, Leyton Obsessionality Inventory, Beck Depression Inventory and a Self Rating of Severity Scale. Changes from pre-treatment to after treatment (post-treatment and followup scores averaged) were signi cantly greater in the DIRT condition than in the control condition for all measures. No signi cant di erences were obtained between groups on post-treatment to follow-up change on any measure. The implications of these ndings for theoretical models of OCD and its management are discussed. # 1998 Elsevier Science Ltd. All rights reserved. 1. Danger ideation reduction therapy (DIRT) for obsessive±compulsive washers: a controlled trial Cognitions focusing on danger and disastrous outcomes have been identi ed in many OCD su erers (Foa, 1979; Yaryura-Tobias and Neziroglu, 1983; Emmelkamp, 1987; Lelliott et al., 1988; Rapoport, 1989; de Silva, 1992; Frost et al., 1994). Further, su erers often overestimate both the probability and the consequences of such events occurring (Yaryura-Tobias and * Corresponding author. Tel.: /98/$19.00 # 1998 Elsevier Science Ltd. All rights reserved. PII: S (98)

2 960 M.K. Jones, R.G. Menzies / Behaviour Research and Therapy 36 (1998) 959±970 Neziroglu, 1983). It has been suggested that the majority of OCD su erers perform compulsions to prevent harmful outcomes (de Silva and Rachman, 1992). In a recent report, Jones and Menzies (1997a) sought to test the validity of a diseaseexpectancy account of OCD washing. They examined the potential mediating roles of danger expectancies and other cognitive variables, including responsibility, perfectionism, anticipated anxiety and self-e cacy in 27 OCD washers. They reported that, of the set of cognitive variables examined, danger expectancies were the most likely mediator of washing-related behaviour in OCD. In particular, they found disease expectancy ratings to be related to both overt and covert measures of verbal-cognitive and behavioural expressions of the disorder. The ability of danger beliefs to relate to all aspects of the condition tested was argued to provide considerable support for danger-based models of OCD. Further, popular alternative constructs such as responsibility and perfectionism were not found to be likely mediators of washing phenomena, failing to remain related to any measure of OCD washing when disease expectancy ratings were held constant in a partial correlation analysis (see further Jones and Menzies, 1997a). In a second study, Jones and Menzies (1997b) assessed whether the level of anxiety, avoidance behaviour and washing-related phenomena could be altered by experimentally manipulating the perceived level of danger in a behavioural avoidance task (BAT). The manipulation involved varying the instructions that subjects were given at the commencement of the BAT. Eighteen undergraduate participants were randomly allocated into either a high or low danger instruction condition. Consistent with an outcome expectancy account of OCD, subjects in the high danger instruction condition were found to have higher mean ratings for anxiety and urge to wash and showed greater avoidance and post-test hand-washing than subjects in the low danger instruction condition 1. Given these ndings and mindful of Carr's (1974, p. 317) call for ``a therapeutic technique that maximises the patient's opportunity for acquiring new subjective estimates of the probability of unfavourable outcomes'', Jones and Menzies (1997c) developed danger ideation reduction therapy (DIRT). This treatment package for OCD washers was speci cally designed to target danger-related cognitions using a variety of procedures to decrease patient estimates of the likelihood of dangerous outcomes. No other biased reasoning styles are addressed by DIRT procedures. For example, unlike the cognitive therapy package of van Oppen and Arntz (1994), in ated personal responsibility is ignored in the present treatment. Additionally, direct and indirect exposure, behavioural experiments, response prevention and serotonin re-uptake inhibitors are not components of the DIRT package. DIRT procedures include corrective information, lmed interviews, cognitive restructuring, microbiological experiments, attentional focusing and Hoekstra's (1989) probability of catastrophe task. In an initial series of case studies trialling DIRT, Jones and Menzies (1997c) reported substantial reductions on four outcome measures in all three OCD subjects at post-treatment. Post-treatment scores on the Maudsley Obsessional Compulsive Inventory (MOCI) (Hodgson and Rachman, 1977) and the Padua Inventory (PI) (Sanavio, 1988) were lower than typical group means for subjects receiving exposure and response prevention in clinical outcome 1 Only the di erences in avoidance scores and post-bat washing reached statistical signi cance in this report.

3 M.K. Jones, R.G. Menzies / Behaviour Research and Therapy 36 (1998) 959± studies (e.g. Emmelkamp and Beens, 1991) and were similar to scores obtained by `normal' control subjects in several reports (e.g. Sternberger and Burns, 1990, 1991). This improvement was maintained at three-month follow-up in all subjects (Jones and Menzies, 1997c). While the DIRT treatment package was associated with clinically-relevant improvement in as few as 6 h of therapy, only tentative conclusions about its e cacy can be drawn from three treatment successes. In order to further examine the e ectiveness of DIRT, a controlled study with a larger sample is required. The aim of the present study is to compare the e cacy of DIRT with a control group who do not receive active treatment. Four self-assessment scales covering contamination-related thoughts, washing behaviours, general OCD severity and depression will be completed by all subjects at pre-treatment, post-treatment and 3-month follow-up. It is hypothesised that subjects who receive eight, 1 h weekly group sessions of DIRT will show greater post-treatment and follow-up reductions in symptomatology than subjects who receive no treatment. It is further hypothesised that those subjects who receive DIRT will continue to improve from post-treatment to follow-up whereas no such di erences will be observed in the control group. 2. Method 2.1. Subjects Subjects were selected from 72 respondents to media announcements of the availability of help for OCD su erers at the Anxiety Disorders Clinic, The University of Sydney. Telephone screening was based on the procedure employed by Lopatka and Rachman (1995) and was designed to establish that subjects met Diagnostic and Statistical Manual of Mental Disorders (DSM-IV) (APA, 1994) criteria for OCD with washing concerns. As part of the screening, subjects had to report that they washed more than 60 min per day or that their cleaning di culties signi cantly interfered with their life. After screening and subsequent con rmatory clinical interviews, 29 people were considered suitable for the study and were o ered inclusion in the experiment. Twenty-three individuals agreed to participate, twelve of whom were randomly allocated to the DIRT treatment while the remaining 11 were placed in the wait list condition. One subject dropped out of each of the two groups before completion leaving 11 subjects in the DIRT group and 10 subjects in the control group Experimental group The sample comprised 11 subjects (all female) with a mean age of 39.0 years. Six subjects had sought treatment for OCD in the past. Five subjects had taken medication for symptom reduction and six subjects had received nonpharmacological interventions such as behaviour therapy, hypnotherapy or counselling. Two of the 11 subjects were taking medication for OCD at the commencement of DIRT. Both were taking uoxetine and these subjects were instructed to remain on the same dosage for the duration of the trial. As an indicator of severity, subjects completed the MOCI (Hodgson and Rachman, 1977). The mean group MOCI score of is considerably higher than typical `normal' group

4 962 M.K. Jones, R.G. Menzies / Behaviour Research and Therapy 36 (1998) 959±970 means reported in the literature (e.g. Sternberger and Burns, 1990) and is similar to other experimental OCD samples (Hodgson and Rachman, 1977; Sternberger and Burns, 1990) Control group The sample comprised 10 subjects (eight female) with a mean age of 38 years. Seven of the 10 subjects had sought treatment for OCD in the past. Seven subjects had taken medication for symptom reduction and six subjects had received nonpharmacological interventions such as behaviour therapy or counselling. Three subjects commenced the trial while taking medication. One was taking sertraline and two uoxetine. All subjects were instructed not to alter their dosage until the completion of the trial. The mean control group MOCI score of 17.6 is considerably higher than typical `normal' group means reported in the literature (e.g. Sternberger and Burns, 1990) and is similar to other experimental OCD samples (Hodgson and Rachman, 1977; Sternberger and Burns, 1990) and the experimental group mean in the present study. Table 1 contains a summary of demographic subject characteristics. The sex distribution obtained is consistent with previous ndings that women dominate OCD washer samples (Dowson, 1977; Stern and Cobb, 1978; Marks, 1987; Rapoport, 1989; de Silva and Rachman, 1992) Procedure Prior to treatment all subjects (experimental and control) were mailed a package which included a subject information sheet, consent form and the following measures. Table 1 Summary of demographic subject characteristics Variable Number experimental control N (n female) 11 (11) 10 (8) Age (years) Mean age Range 21±55 24±61 Relationship status Married 3 3 Single 6 6 Divorced 2 1 Occupational status Full time 4 2 Part time 2 4 Unemployed 5 4 Years of education Mean

5 M.K. Jones, R.G. Menzies / Behaviour Research and Therapy 36 (1998) 959± Self-rating of severity (SRS) This 9-point self-rating of severity was adapted from the measure developed by Marks and Mathews (1979) for use with phobic clients. Subjects respond to the following question: ``How would you rate the present state of your obsessive±compulsive symptoms on the scale below?'' On the scale, 0 represents no OCD present, while the maximum score of 8 represents a very severe, disturbing or disabling OCD present Maudsley obsessional±compulsive inventory This questionnaire, developed by Hodgson and Rachman (1977) is a 30-item, self-report, true±false scale designed to measure the total frequency of OCD symptoms. A total score as well as washing, checking, slowness and doubting subscale scores may be determined. The MOCI remains one of the most popular measures of OCD and there is considerable evidence that the MOCI can register changes in symptom severity Beck depression inventory (BDI) This 21-item self-report questionnaire measuring the severity of depressive symptoms was developed by Beck et al. (1961). The 21 items have a range of 0±3. It remains a widely used measure of depression Leyton obsessional inventory (LOI) This instrument, developed by Cooper (1970), is a 69-question inventory designed to assess obsessive±compulsive symptoms. The paper-and-pencil form of the LOI was used (Snowdon, 1980). In addition to `yes' or `no' responses to each item, scores are generated for feelings of `resistance' and the degree of `interference' with other activities caused by the item. The resistance and interference items have a range of 0 to 3. Resistance and interference scores were summed and added to the number of `yes' item responses to give a total LOI score Treatment Treatment was conducted by the Director of the Anxiety Disorders Clinic, the University of Sydney (the second author) who has 13 years of clinical experience in the cognitive-behavioural management of the anxiety disorders and previous experience in the administration of the DIRT package. Subjects in the wait list control group did not receive any treatment 2. Treatment for the experimental group consisted of eight 1-h sessions in groups of ve or six individuals. The sessions were run over a nine week period due to a one week University mid-semester recess. The sessions were conducted on the same day each week at two di erent times and subjects were told that as the content was the same for both group sessions they could attend either session at their leisure. The components of the treatment package are described in Section All wait list subjects were o ered treatment after follow-up testing.

6 964 M.K. Jones, R.G. Menzies / Behaviour Research and Therapy 36 (1998) 959± DIRT Cognitive restructuring This component combined elements of systematic rational restructuring (Goldfried and Goldfried, 1980) and rational-emotive therapy (Ellis, 1962) and was modelled on the procedures described by Mattick et al. (1989) and Menzies and Clarke (1995). Subjects identi ed their irrational thoughts related to contamination and were asked to reevaluate these thoughts, changing them to be more realistic and appropriate to the demands of the situation. Once constructed, subjects were asked to rote-learn their reappraisals, reading and copying them on a daily basis for 15 min. In later sessions, subjects were shown how to apply their reappraisals to novel situations. Subjects received 120 min instruction in cognitive restructuring within sessions Filmed interviews A series of 10-min lmed interviews with various workers who had regular contact with contamination-related stimuli were presented. Each interviewee described in detail their repetitive contact with OCD-related stimuli (e.g. bodily uids, dirt, animal hair, money). The absence of work-related illnesses in each interviewed subject was highlighted. Professionals interviewed included medical practitioners, nurses, cleaners, bank tellers, gardeners, printers and laboratory workers. Subjects received a total of 60 min of this component within sessions Microbiological experiments Discussion of the results of a series of microbiological experiments concerning contamination formed the basis of one 60 min treatment session. The experiments had been previously conducted in conjunction with the Microbiology Department of the University of Sydney. The experiments involved the authors `contaminating' one hand by touching a particular stimulus commonly found to be anxiety provoking to OCD-washers. The second hand, which did not come into contact with the stimuli, acted as a control. The tasks included shaking hands with 38 people, stroking a cat, touching a plastic implement which had been used to scoop out a cat litter tray, touching the lining of a garbage bin and touching the doors of a public toilet. The number and type of microorganisms present on the control hand were analysed and compared with those on the hand which had performed the various tasks. The micro ora were isolated from nger prints on microbiological agar plates (sheep blood agar plates) and the plates were incubated for 24 h at 378C. The number of organisms growing on the plates at each ngerprint site were counted and ascertained for potential pathogenicity. After such analysis none of the colonies that grew on the blood plates showed any haemolytic e ect on the blood in the medium. No potentially pathogenic organisms were isolated on either the control or the task plates. The microbiologist concluded that none of the tasks involved contamination of the hand with any organisms that were other than normal commensal ora of the skin. A twopage report summarising the results of these tests was given to each subject. Discussion of the results centred on challenging subject's previous excessive risk estimates associated with these tasks.

7 M.K. Jones, R.G. Menzies / Behaviour Research and Therapy 36 (1998) 959± The probability of catastrophe As described by Hoekstra (1989), this procedure involved comparing subject estimates of the probability of a negative outcome with an estimate derived from an analysis of the sequence of events that might lead to the feared event. Behaviours, such as throwing out the garbage, were broken down into the sequence of events required for contamination or illness to occur (e.g. bacteria present on garbage bin, bacterial transfer to hand, bacteria entering the body, initial immune system failure). Probability estimates for each step in the sequence were given by the subject. These were multiplied together to give an estimate of the likelihood of illness which, in all cases, was much larger than the subject's initial global estimate. Discrepancies between subject's global estimates and that obtained through the probability sequencing task were highlighted and discussed. Subjects received 60 min practice in this technique within sessions. Homework consisted of applying this method to one novel situation each week Corrective information Each subject received a list of facts related to illness and death rates in various occupational groups (e.g. the number of health care workers who had occupationally contracted Human Immunode ciency Virus). The information highlighted common misconceptions about illness and disease and the ease with which a variety of conditions can be contracted. Additional information was provided to subjects concerning the problems inherent with excessive hand-washing. This included a one-page report from the Department of Microbiology, The University of Sydney which stated, in part, that; Vigorous hand-washing will reduce the numbers of bacteria found on the skin but will not eliminate them because the microorganisms found deep within the pores and follicles will re-establish the population. Infections of the skin usually arise at a site where there is minor trauma where the integrity of the skin has been interrupted. Vigorous washing can damage the integrity of the skin causing cracks and ssures thus breaking down the protective barrier to infection. These cracks can become the portal of entry for pathogens which have the potential to cause deepseated infections. The implications of this report and all additional information given to subjects for handwashing practice were discussed. Subjects participated in 60 min of discussion of this corrective information within sessions Attentional focusing This procedure, described in detail by Clarke and Wardman (1985), involved a focusing task that aimed to reduce the frequency of threat-related intrusive thoughts by increasing the subject's ability to attend to alternative cognitive targets in a rhythmic breathing exercise. Subjects were taught to focus on a series of numbers while breathing in and to focus on the word `relax' while breathing out. Subjects were instructed to breathe normally and not to slow or speed up the respiration rate. Subjects initially trained with eyes closed in a quiet location with minimal noise and distraction. As training progressed across weeks, subjects were instructed to increasingly complete their daily focusing sessions in noisier environments with eyes open. Daily practice consisted of two, 10-min focusing sessions. This technique has

8 966 M.K. Jones, R.G. Menzies / Behaviour Research and Therapy 36 (1998) 959±970 recently been shown to reduce intrusive danger-related thoughts in both analogue and clinically anxious groups (Sahebi and Menzies, 1997). Subjects received 60 min instruction and practice in attentional focusing within sessions (see further in Clarke and Wardman, 1985) Post-treatment assessment and follow-up At the completion of the nal treatment session experimental subjects were given the Self- Rating of Severity (SRS), Maudsley Obsessional Compulsive Inventory (Hodgson and Rachman, 1977, Beck Depression Inventory (BDI) (Beck et al., 1961), Leyton Obsessional Inventory (LOI) (Cooper, 1970; Snowdon, 1980) and asked to complete them at home and mail them back to the clinic within the week. At the same time control subjects were sent the same questionnaires and were also asked to complete and mail back the measures. Three months after the nal treatment session all participants were sent the questionnaires again with the instruction to complete them and mail them back to the researchers within one week of receipt Statistical analyses For each of the dependent measures, between and within group treatment di erences were examined in a repeated measures ANOVA using a complete set of orthogonal planned contrasts. 3. Results 3.1. Treatment e ects Table 2 presents the outcome data for the DIRT and wait list groups. As can be seen in Table 2, large di erences from before to after treatment were evident on all measures for the experimental group compared to the control group. The interaction contrasts revealed the superiority of DIRT over no treatment. Changes from pre-treatment to after treatment (posttreatment and follow-up scores averaged) were signi cantly greater in the DIRT condition than in the non-dirt condition on the Self-rating of Severity (F[1, 19] = 25.78, p < ), Maudsley Obsessional Compulsive Inventory (F[1, 19] = 12.89, p < 0.005), Beck Depression Inventory (F[1, 19] = 8.97, p < 0.01) and the Leyton Obsessional Inventory (F[1, 19] = 24.32, p < ). Despite trends in the expected direction, interaction contrasts failed to reveal signi cant group di erences in post-treatment to follow-up change. Non-signi cant di erences between groups were found on post-treatment to follow-up change on the Self-Rating of Severity (F[1, 19] = 4.01, p = 0.06), Maudsley Obsessional Compulsive Inventory (F[1, 19] = 0.66, p = 0.43), Beck Depression Inventory (F[1, 19] = 1.76, p = 0.20) and the Leyton Obsessional Inventory (F[1, 19] = 2.98, p = 0.10). In sum, large changes followed treatment, with little further improvement at follow-up.

9 M.K. Jones, R.G. Menzies / Behaviour Research and Therapy 36 (1998) 959± Table 2 2(Treatment, no treatment) 3(pre, post, follow-up) outcome data Group Measures Testing Stage treatment no treatment SRS pre post follow-up MOCI pre post follow-up BDI pre post follow-up LOI pre post follow-up SRS = Self-Rating of Severity; MOCI = The Maudsley Obsessional Compulsive Inventory; BDI = The Beck Depression Inventory; LOI = The Leyton Obsessional Inventory. 4. Discussion Moderately e ective treatment for OCD has been available for the past thirty years. At present, the treatments of choice for OCD are behaviour therapy, consisting of exposure and response prevention and serotonin re-uptake inhibiting medications of which clomipramine remains the most well researched. However, neither therapy approach produces symptom-free behaviour in many OCD su erers. It has been estimated that 20 to 30% of patients refuse to participate or dropout from behavioural treatment programmes (Rachman and Hodgson, 1980; Baer and Minichiello, 1990). Further, as Jenike (1990) argues, OCD tends to respond to medication only partially, typically with between 30 and 60% symptom reduction. OCD patients tend to remain chronically symptomatic despite the best pharmacologic interventions (White and Cole, 1990). In summary, with the best available treatment, `cure' of OCD is still not commonplace. DIRT appears to have several potential advantages over behavioural and pharmacological treatments. First, unlike exposure and response prevention, DIRT does not involve interactions with anxiety-provoking stimuli. This is particularly important since so many su erers either refuse exposure treatment or drop-out before completion because of its anxiety-provoking e ects. Second, unlike clomipramine, DIRT does not produce any physical side e ects. Third, DIRT is a highly structured treatment package involving lms, structured reports and exercises which are relatively inexpensive to package and administer. Fourth, DIRT appears to require relatively few sessions for its therapeutic e ect.

10 968 M.K. Jones, R.G. Menzies / Behaviour Research and Therapy 36 (1998) 959±970 In the present study subjects who received DIRT showed signi cantly greater reductions in symptomatology from pre-treatment to after treatment on all four outcome measures than subjects who did not receive DIRT. However, no signi cant di erences between groups were obtained in post-treatment to follow-up change on any measure. While DIRT appears to have been e ective in reducing OCD symptomatology, the clinical improvements obtained were not as large as expected. In particular, the post-treatment mean MOCI score was somewhat higher than typical group means for subjects receiving exposure and response prevention in clinical outcome studies (e.g. Emmelkamp and Beens, 1991) and considerably higher than scores obtained by `normal' control subjects in several reports (e.g. Sternberger and Burns, 1990, 1991). Clearly, the present ndings are not as impressive as those reported by Jones and Menzies (1997c) in the initial trial of DIRT. In this earlier report, post-treatment scores on the MOCI were comparable to, or lower, than group means for subjects receiving response prevention in several studies (e.g. Emmelkamp and Beens, 1991) and were similar to scores obtained by `normal' control subjects in several reports (e.g. Sternberger and Burns, 1990, 1991; Jones and Menzies, 1997c). A number of factors may explain the di erences in the relative e ectiveness of DIRT reported in the two trials of the treatment package. Firstly, in the present study, DIRT was carried out in groups rather than in individual sessions. It is conceivable that DIRT is more e ective when presented in individual sessions in which the therapist is more aware of the dysfunctional beliefs of the individual client and then assists the client in identifying appropriate challenges. In the group DIRT treatment, less attention was given to individual's idiosyncratic beliefs. The techniques were taught and clients urged to apply them with less intensive therapist guidance than in the individual therapy provided in the rst DIRT trial. Also, clients may not have wanted to discuss their concerns or ask for clari cation of techniques in front of others due to embarrassment or fear of looking silly. In the present study subjects were informed that they would not be required to read out their inappropriate or unhelpful cognitions unless they wished to. Additionally, the three subjects in the initial DIRT trial (i.e. Jones and Menzies, 1997c) received treatment until two conditions were satis ed: (1) Clinically signi cant gains were apparent with minimal symptomatology remaining. (2) The subject displayed a sound grasp of the cognitive model underpinning DIRT procedures. These conditions were satis ed in between six and ten individual sessions in all three cases. In the present study, no such conditions were used as a guide to terminate treatment. It was decided from the outset, admittedly on the basis of the case study results, that treatment would involve only eight sessions regardless of clinical gains or the client's understanding of the model underpinning DIRT procedures. Finally, the expectations of the three subjects who received DIRT in the rst trial may have contributed to the di erences in treatment e ectiveness observed in the two DIRT studies. Given that all three subjects in Jones and Menzies (1997c) earlier study had refused to undergo exposure and response prevention, they may have been highly motivated to respond to what they considered to be their only remaining option for treatment. On the basis of only two studies it is too early to determine how e ective this non-exposure, non-pharmacological treatment will prove to be in OCD. Clearly, future research needs to be

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