&im. Res. The?. Vol. 27, i%. I. pp. 89-93. 1989 WJOS-7967,‘89 S3.00 + 0.00 Printed in Great Britain. All rights reserved Copyright & 1989 Pergaman Press pk

CASE HISTORIES AND SHORTER COMMUNICATIONS

Home-based sealant of o~~iv~ornpu~ive patients: intersession interval and therapist involvement

PAUL M. G. EMMELKAMP, CHIQUIT VAN LINDES VAN DEN WEWELL, MARJOLEIN RUPHAN and ROBBERT SASDERMAN

Deportment of Clinical Psychology, Wniversity of Groningen, Academic HospitoI. Oosrersirzgei 59, 9713 EZ Groningen, The .~elherian~

(Received 9 February 1988)

Summary-In a 2 x 2 factorial design massed vs spaced and therapist vs self-controlled exposure were compared with obsessive-compulsive patients. Intersession interval was varied keeping constant the length of exposure time and number of exposure sessions. Treatment in all conditions was home based. Treatment led to highly statistical and significant improvements on all measures. Massed exposure was as effective as spaced exposure; self-controlled exposure proved to be as effective as therapist~ontroll~ exposure.

The impact of variations in the scheduling of therapy sessions on the outcome of therapy has received more interest from researchers in the field of psychotherapy than from behavior therapists. As far as psychotherapy is concerned, most studies reveal no significant differences in outcome between more or less frequent schedules (Orlinsky and Howard, 1986). The duration of intersession intervals did not affect outcome with desentization in an analogue studies by Hall and Hinkle (1972). The only clinical study so far was reported by Foa, Jameson, Turner and Pavnes (1980). who investigated the differential effects of massed and spaced sessions of exposure in vivo with 1 f agoraphodics. Results indicated that both massed and spaced sessions of exposure in uivo effected changes, massed practice being superior. Given the specific population (agoraphobics) and the small number of patients involved in this study there is clear need for investigating this issue with other anxiety disorders.

Especially with obsessivecompulsive the issue of variations in the scheduling of sessions is both theoretically and practically of importance. Theoretically, massing of extinction trials increases the rate of extinction (Mackintosh, 1974). Rachman (1980) has suggested that infrequent practice and avoidance of disturbing stimuli or situations may impede satisfactory emotional processing. The issue of scheduling exposure session is also of clinical relevance. The behavioral treatment of obsessive+ompulsives is mostly applied in a hospital setting involving daily exposure session (e.g. Rachman, Hodgson and Marks, 1971; Hodgson, Rachman and Marks, 1972; Rachman, Marks and Hodgson, 1973; Rachman, Cobb, MacDonald, Mawson, Sartory and Stern, 1979; Foa, Steketee and Grayson. 1985; Foa, Steketee, Grayson, Turner and Latimer, 1984; Foa, Steketee and Milby, 1980; Foa, Steketee, Turner and Fisher, 1980) and sometimes even involving continuous supervision (Meyer, Levi and Schnurer, 1974, Heyse, 1973; Mills. Agras, Barlow and Mills, 1973). In our own studies, however, patients have been treated at their homes and treatment was scheduled either 3 times (Boersma. Den Hen@, Dekker and Emmelkamp, 1976) or twice a week (Emmeikamp and De Lange, 1983; Emmelkamp and Kraanen, 1977; Emmelkamu, van de Helm, Van Zanten and Piochn. 1980: Emmeikamo. Visser and Hoekstra. 1988). Obviouslv. in the case of home based treatment daily treatment sessi&s are’hardly to realize, especially when obsessive-compulsive patients do not live in the vicinity of the treatment agency.

A related issue is whether exposure and response prevention needs to be directed by the therapist or can be administered by the patient in his or her natural environment. In a pilot study by Emmelkamp and Kraanen (1977) the effects of therapist-controlled exposure and self-controlled exposure were compared. Although no significant differences were found between the two conditions. elf-controli~ exposure was consistently superior to therapist~ontroil~ exposure at l-month follow-up. This suggests that self-controlled exposure at home is not only cost-effective but also might result in superior maintenance of treatment-produced change. However, given the small number of patients involved in this study there was a clear need of studying this issue further.

The present experiment was designed to explore optimal conditions for home-based treatment. Therefore. intersession interval was varied, keeping constant the length of exposure time and number of exposure sessions. In order to study the e&t of therapist involvement, with half of the patient exposure sessions were self-controlled. whereas with the other half the exposure sessions were conducted by the therapist.

Design

METHOD

In a 2 x 2 factorial design massed vs spaced and therapist-controlled vs self-controlled exposure were compared. After an intake interview patients were randomly allocated to therapist-controlled exposure or to self-controlled exposure. With half of the patients in each condition practice was massed, with the other half of the patients practice was spaced. In the massed practice condition exposure sessions were conducted 4 times a week, whereas in the spaced exposure condition sessions were held only twice a week.

The first three sessions were devoted to the pretest and preparation of the treatment. Then, ten exposure sessions followed. After the experimental treatment a posttest was held, and Follow-up I took place 1 month later. No treatment was provided during this period. Treatment was continued after Follow-up 1 but adapted to the individual needs of the patients. Six months after the posttest Follow-up II was held.

89

90 CASE HISTORIES AND SHORTER COMMIJ’N~CATIOKS

Palienls

Obsessive-compulsive patients who were considered for this study were referred to our department by mental-health agencies and general practitioners. Two patients were self referred. The program acceptance criteria were:

(a) primary diagnosis of obsessive-compulsive disorder. The obsessive*ompulsive behavior (ritual) had to be the main problem and severe enough to warrant intensive treatment;

(b) no previous behavioral treatment.

Of 22 patients who were referred for treatment, six were not accepted for this study: the problems of four of them were not severe enough; one had been treated previously with behavior therapy; and another one appeared to be psychotic rather than obsessional. Thus 16 patients met the research criteria. Two patients dropped out before treatment. One patient did not accept the treatment rationale and refused treatment. Another patient could not fulfill the research requirements due to a serious illness of her husband. Thus, 14 patients completed the project, 7 in each main condition. Their average age was 34yr. the range 17-68 yr. The avearage duration of the complaints was 6yr, the range I-14yr.

Therapists

Therapists were 9 advanced clinical psychology students (7 male, 2 female) who had received training in behavior therapy. Twice a week group sessions were held, where problems which occurred during treatment were discussed. The therapists were supervised by the senior author.

Trearmenl

The patient was instructed not to take any anxiety-reducing or anti-depressant drug during the treatment. Before the therapy was begun, an inventory was drawn up for each client of the stimuli which might trigger compulsive rituals. Next, a hierarchy was constructed. The extent of exposure and the extent of response prevention were together structured into one hierarchy. Patients who worked through the hierarchy at a high speed had to practise old items again to ensure that they would not have dealt with all the items before the seventh treatment session.

With Therapist-controlled exposure in civo, the patients’ home was chosen as the place of treatment. Each session lasted 2 hr. The members of the patients’ family were instructed to be absent during the treatment sessions. The treatment in this condition was the same as in the study by Boersma er al. (1976): gradual exposure plus gradual response prevention. All the items in the hierarchy were practised in civo, starting with the easiest, with the therapist present. As a rule, the patients themselves determined the speed at which they worked through the hierarchy. If a patient tried to avoid treatment by not choosing a new item for practice, some pressure was exerted to induce the patient to carry on practising. If the whole hierarchy of items had been worked through before the end of the treatment, practice of the most difficult items was repeated during the last sessions.

With Self-controlled exposure in vivo, patients were treated as out-patients at the department of Clinical Psychology in Groningen. Each treatment session lasted only 45 min. At each session the patient was given a number of tasks (items from the hierarchy) which he had to perform by himself at home. These tasks were described clearly, written down and discussed with the patient at length. At the beginning of each new session, the patients’ performance of the tasks of the previous session was discussed. All the items in the hierarchy had to be practised in oivo, starting with the easiest. The speed at which the patients worked through the hierarchy was the same as with the therapist-controlled exposure in uivo.

In this condition, the treatment actually consisted of 2 components: self-controlled exposure in viuo and self-imposed response prevention. The therapist was never present when the client performed the tasks; nor was there any practising of the tasks during the session at the department. For details and practical guidelines of the treatment procedures the reader is referred to Emmelkamp (1982).

There were four experimental conditions:

Massed-therapist-controlled: In a 2.5 wk period ten 2 hr exposure sessions were conducted with therapist guidance. Massed-self-controlled: In a 2.5 wk period the patient had to practice all alone IO times for 2 hr each. After 2 such

“exposure sessions” a session with the therapist was scheduled at the department to discuss the exercises. Spaced-[herapist-confrolIed: In a 5 wk period ten 2 hr exposure sessions were conducted with therapist guidance. Spaced-self-controlled: In a 5 wk period the patient had to practice all alone 10 times for 2 hr each. After 2 “exposure

sessions” a session with therapist was scheduled at the department to discuss the exercises.

Assessmenls

Pretest, posttest and Follow-up I and II were carried out by client and therapist. In addition an independent observer, a clinical psychologist, rated the client before and after the treatment.

I. Obsessive-Compulsive Targets (1) Anxiefy discomfort scale. Patient, therapist and independent observer rated five situations on O-8 scales for anxiety

discomfort. The scores for the 5 situations were averaged. (2) Maudsley Obsessiona! Compulsive Inventory (MOCI; Hodgson and Rachman, 1980).

II. Mood measures (3) Anxious mood and depression. Therapist and independent observer rated the client on O-8 scales for anxious mood

and depression (Watson and Marks, 1971).

The clients also filled in the following questionnaire: (4) Self-raring depression scale (SDS-Zung, 1965). Range 23-92.

RESULTS

Results are presented in Table 1. Multivariate analysis of variance revealed a significant time effect on all measures. Contrasts revealed that the improvement occurred between pretest and posttest and was statistically significant on all measures (P c 0.001). Two of the contrasts between posttest and follow-up I revealed a slight, but significant relapse at follow-up: MOCI and depression as rated by the therapist (F = 7.57, P c 0.02) and on MOCI (F = 4.85, P < 0.05).

Neither a significant between group effect, nor a significant interaction effect was found, thus showing that there were no differences between conditions.

CASE HISTORIES AND SHORTER COMMtiNICATlONS 91

Table I. Means and standard deviations (in parentheses) at pretest. posttest and Follow-up I

Pre Post Follow-up Time effect

Obsessivccompulsive problems Anxiety-discomfort P 5.6 1.7 2.3 2 I ,940

(1.3) (1.6) (2.1) T 6.1 2.1 2.3 23.49.’

(0.9) (1.6) (2.2) MOCI 14.8 6.3 8.1 l6.02**

(5.3) (4.6) (4.4) Mood measures

SDS 58.5 49.1 50.6 9.15. 18.3) (12.61 (13.81

Depression

Anxious mood

T ‘4.0’ ~ 1.9’ i 2.9’ 10.99’. (2.0) (1.9) (2.5)

T 4.4 2.3 2.4 12.24” (1.7) (1.7) (2.1)

MOCI = Maudsley Obsessive-Compulsive Inventory; SDS = Self-rating Depression Scale. l P < 0.005; l *f <0.002; l **f < O.OOQI. P = patient; T = therapist.

Independent assessor

The independent assessor rating at pretest and posttest was analysed with r-tests. This analysis revealed significant improvements on all measures (P c 0.05) except depression in the therapist controlled exposure condition.

Statistical and clinical significance

To assess the statistical significance of the effects achieved, effect sizes were calculated by means of Cohen’s d (Cohen, 1977) on the pretest-follow-up difference. Results are shown in Table 2. Except for depression as rated by the therapist (medium effect size) the effect size for all other measures is large.

To assess the clinical significance of the effects achieved patients were categorized according to improvement on the O-8 anxiety-discomfort scale. The degree of improvement was defined as follows: (a) symptom free: score < 1.5 at posttest or follow-up; (b) much improved: improvement of at least 4 points; (c) improved: improvement of at least 2 points; (d) unimproved: improvement of less than 2 points. Results are shown in Table 3. Clearly most clients benefitted from the treatments.

Additional treatment

After Follow-up I most patients (II out of 14) received further treatment adapted to the individual needs, consisting of further exposure sessions (n = 6) assertiveness training (n = 3), marital therapy (n = I). cognitive therapy (n = 3). and grief therapy (n = 1). Thus the results of the individual treatments could not be assessed at the 6 month follow-up. A comparison of the results (conditions pooled) at pretest and Follow-up II revealed that the results were maintained. (r-tests for dependent samples, P at least <0.02).

DISCUSSION

The results of this study indicate that there were no differences between both major variables: massed exposure was as effective as space exposure; and self-controlled exposure was as effective as therapist-controlled exposure. The finding that intersession interval was not related to outcome is at odds with the finding of Foa er al. (1980) who did find a significant

Table 2. Indices of Effect Size (Cohen’s d) of differences between pretest and Follow-up I

n

Obsessive-Compulsive Problems Anxiety-discomfort P 1.92

T 2.30 MOCI 1.37

Mood measures SDS 0.72 Depression T 0.51 Anxious mood T I.11

For purpose of interpretation Cohen (1977) considers a d of 20 small, a d of 0.5 medium and a d of 0.80 large.

Table 3. Number of patients rated as improved at posttest and Follow-up I on the anxietv-discomfort scale

Symptom Much free improved Improved Unimproved

Posttest P 6 2 4 2

T 6 I 4 3 Follow-up

P 1 I 3 3 7 fG 1 I A

P = patient; T = therapist

92 CASE HISTORIES AND SHORTER COMML-NICATIONS

difference in favor of massed exposure. Foa er al., however, found the difference only on avoidance rating, not on anxiety. Further, the sample in that study was rather small. Finally, their study was conducted on agoraphobics, who may not be directly comparable to the obsessive-compulsives of the present study.

There is no evidence that giving patients more opportunity to avoid the stimuli in between the treatment sessions, as was done in the spaced condition impedes progress. Theoretically, one could expect an increment of anxiety in the spaced condition (Mackintosh, 1974; Rachman, 1980). but this was not found in the present study. Probably with briefer exposure sessions sensitization in between treatment sessions may be expected when exposure sessions are spaced (Marshall, 1985). It should be noted that in the present study each exposure session lasted 2 hr to ensure that habituation would occur.

The results are also of practical importance: the finding of no difference between massed and spaced exposure means that it is not necessary to expose patients each day in order to achieve improvement. Results clearly show that it is possible to give exposure treatment home-based with a limited frequency of sessions of twice a week: for at least a number of obsessive-compulsives hospitalisation is not necessary, since similar effects can also be achieved when treated in their own environment. Actually, a recent study found no difference in effects between our home-based treatment and hospital-based treatment of obsessive-compulsives (Van der Hout, Emmelkamp, Kraaykamp and Griez, 1988).

The finding that self-controlled exposure was as effective as therapist-controlled exposure corroborates the findings of our pilot-study (Emmelkamp and Kraanen, 1977). This means that with at least a number of obsessive+zompulsives the therapist intervention can be limited to instructing the patients to do the exercises on their own. Of course this does not mean that therapist intervention is supertluous. It should be reminded that after two sessions the patient and the therapist met together to discuss the progress and the performance of the patient. It is highly unlikely that serious obsessive-compulsives as in this study would manage to do the exercises all alone without any intervention from the therapist throughout the treatment. It was often necessary to motivate patients when they had a relapse during treatment or when they felt no real need to do the exercises. Further, the role of reinforcement from the therapist throughout the treatment should also not be ignored. Nevertheless, results indicate that self-controlled exposure is a very cost-effective method for obsessive-compulsives.

Although we did not find a statistically significant difference between therapist-controlled and self-controlled exposure, clinically there are reasons to believe that self-controlled exposure may even be superior for some obsessive-compulsives, especially for patients with checking rituals. Those patients often do not feel responsible in the presence of someone else, e.g. the therapist. When they have to do the exposure exercises all alone, they really are responsible themselves. When the therapist is present, and they are not allowed to check, there is no question of genuine exposure. In clinical practice the individual needs of patients should determine whether the exposure program should be therapist-controlled or self- controlled. Clinically, it makes sense with a number of obsessivecompulsives to start with a few sessions of therapist- controlled exposure followed by a self-controlled exposure program as was done with agoraphobics in the study by Emmelkamp and Wessels (1975) and Emmelkamp (1974). Studies investigating whether a combination of therapist- controlled exposure and self-controlled exposure enhances the effects of each procedure on its own are particularly welcome.

With a number of obsessive-compulsives treatment had to be continued after the experimental trial and was adapted to the individual needs of the patient. Additional treatments included cognitive therapy, assertiveness training, marital therapy and grief therapy. Another issue deserving further study is whether treatment based on a functional behavioral analysis of the patients’ problems is more effective than a standardized exposure and response prevention programme.

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