RESUMEN
El uso de placebos y diseños a doble ciego ha cumplido un papel crucial en la investigación clínica en Medicina. Su aplicación a la investigación de resultados en psicoterapia ha sido controversial. Muchos autores niegan la posibilidad de su aplicación debido a que el terapeuta debería conocer la condición del procedimiento aplicado. Se presenta detalladamente un estudio en el que se utilizó un procedimiento placebo correspondiente a EMDR (Eye Movement Desensitization and Reprocessing- Desensibilización y Reprocesamiento por Movimientos Oculares) con un Diseño Experimental de Caso Único. Los objetivos fueron los siguientes: poner a prueba la viabilidad de la implementación de un placebo de tipo psicológico en EMDR y la aplicación de un diseño a doble ciego en el estudio de resultados en EMDR. Se seleccionaron tres pacientes que sufrían de Trastorno por Estrés Postraumático. Se estableció una línea de base de la sintomatología presentada. Luego, los sujetos fueron asignados aleatoriamente a tres condiciones experimentales durante tres sesiones: (a) aplicación del protocolo EMDR sin ningún tipo de estimulación con auriculares en silencio (placebo 1), (b) aplicación del protocolo EMDR con estimulación bilateral auditiva simultánea (no alternada) (placebo 2) y (c) aplicación del protocolo estándar de EMDR con estimulación auditiva bilateral alternada (tratamiento activo). Tales procedimientos resultaron igualmente creíbles para el paciente y para el terapeuta. Esto permitió el desarrollo de un diseño de investigación a doble ciego para la investigación de resultados en EMDR. Finalmente, se discuten algunas posibles aplicaciones e implicancias de la introducción del uso de placebos psicológicos y diseño a doble ciego en la investigación en psicoterapia.
Double blind design and placebos have been of crucial importance in medical clinical research. Their use in outcomes research in the field of psychotherapy has been controversial, though. Their feasibility in such case has been denied by many authors based on the assumption that the psychotherapist would need to know the nature of the applied procedure. In view of this, the author has conducted a pilot feasibility study on three subjects within the context of his doctoral dissertation. Said dissertation aims at establishing the role of alternating bilateral auditory stimulation in the processing of traumatic memories as used in the EMDR (Eye Movement Desensitization and Reprocessing) technique. To such end, the EMDR basic principles and procedures are introduced -with particular attention to alternating bilateral auditory stimulation- and a pilot study using placebos during EMDR administration is presented in detail. The goals of this study are testing the feasibility of: (a) using a psychological placebo in EMDR therapy, and (b) applying a double blind design study in EMDR outcomes research. A single case experimental design was performed on three different patients suffering from PTSD (Posttraumatic Stress Disorder). A symptomatology baseline was established through out three weekly sessions using the DTS (Davidson Trauma Scale) and the OQ-45.2 (Outcomes Questionnaire 45.2). First, three CDs were recorded -one with no sound at all (CD-1, silence condition); another one with auditory stimulation consisting of a tic-tac sound recorded in monaural condition, and reproduced simultaneously over both earphones at a rate of one beat per second (CD-2, monaural condition) and a third one with alternating bilateral auditory stimulation consisting of the exact same sound recorded in stereophonic condition, and reproduced alternatively over the left and right earphones (CD-3, stereo condition)-. At a second stage, these three experimental conditions were assigned randomly to the three subjects, who were administered: (a) EMDR protocol without any type of stimulation, with no sound coming out of the earphones using CD-1 (placebo 1), (b) EMDR protocol with simultaneous bilateral auditory stimulation using CD-2 (placebo 2), and (c) EMDR protocol with alternating bilateral auditory stimulation using CD-3 (active treatment). In all cases, the experimental conditions were implemented during three full sessions in which the CDs were reproduced for the subjects through earphones, instead of speakers, to ensure that the psychotherapist was unaware of the actual conditions. Subsequently, the standard EMDR protocol (i.e., with alternating bilateral auditory stimulation) was administered to each subject until the end of the treatment, determined either by the symptoms being resolved or the maximum of ten sessions being completed. As a result of this pilot study, the author concludes that the feasibility of using double blind studies and placebos in EMDR psychotherapy has indeed been established. Since no apparent difficulties in the administration of the placebos were detected during the study, the use of psychological placebos seems viable. Such procedure is equally credible for the patient as well as for the psychotherapist, which renders possible the development of a double blind design in EMDR outcomes research. It should be noted, though, that the credibility of the placebo was not formally assessed, but rather was perceived through the author’s informal observation. Developing assessment criteria and formal tools to evaluate the credibility of placebo procedures is advisable if future investigations on the subject are to be carried. Even though this study was conducted under a Single Case Experimental Design, the placebo procedure employed could be easily adapted for its use in between group’s designs. Finally, some of the possible applications and consequences regarding the introduction of placebos and double blind design in psychotherapy research are discussed.
RESUMEN
En este estudio se evalúa la efectividad de la psicoterapia individual realizada por terapeutas noveles en la Clínica Psicológica de la Universidad de La Frontera (Temuco - Chile) y su relación con la alianza terapéutica. La investigación es de carácter cuantitativo, con diseño de grupo único y evaluaciones al inicio y término de la terapia. En el estudio participaron 23 consultantes, cuyos procesos psicoterapéuticos eran conducidos por 11 estudiantes de los últimos niveles de la Carrera de Psicología, que realizaban su primera experiencia en atención psicoterapéutica supervisada, o se encontraban efectuando su práctica profesional. Los instrumentos utilizados fueron las versiones adaptadas para Chile del Outcome Questionnaire (OQ-45.2) de De la Parra y Von Bergen (2000, 2002) que permite evaluar el nivel de cambio en el curso de la terapia y sus resultados finales y del Working Alliance Inventory (Inventario de Alianza de Trabajo, IAT-P) de Santibáñez (2001) que evalúa la alianza terapéutica desde la perspectiva del paciente. Los resultados informan diferencias significativas entre la primera y última aplicación del OQ-45.2. Los puntajes obtenidos en el IAT-P están ubicados en los dos tercios superiores de la escala, observándose una restricción de rango con sesgo positivo. Se evidencia una asociación significativa entre la alianza terapéutica percibida por el paciente y el resultado de la psicoterapia, tanto en el puntaje total de la escala OQ-45.2, como en la Subescala de Síntomas. Estos resultados son discutidos considerando la investigación actual en el área y el trabajo realizado por terapeutas noveles.
The present study was aimed to assess the effectiveness of individual psychotherapy undertaken at the Psychological Clinic of the Universidad de La Frontera (Temuco, Chile) and its relationship with the therapeutic alliance. The investigation involved 23 adult patients with neurotic symptoms. Their therapeutic processes were carried out by 11 trainee students from the regular psychology training program. Out of these, 4 therapists were performing their first supervised psychotherapeutic experience, and 7 therapists were undertaking their professional training using either a psychodynamic or a humanistic- experiential approach. The therapeutic processes considered in this study lasted between 5 and 42 sessions, comprising the following closure modalities: agreed closure between the patient and therapist because of the fulfillment of objectives, closure requested by the patient, and withdrawal of the therapeutic process. The instruments used were the Outcome Questionnaire (OQ-45.2) adapted for Chilean population by De la Parra and Von Bergen (2000, 2002), an instrument that allows to evaluate the level of change in the final course of the therapy and its outcomes; and the Working Alliance Inventory (Inventario de Alianza Terapéutica, IAT-P) adapted for Chilean population by Santibánez (2001), an instrument that evaluates the level of therapeutic alliance from the perspective of the patient. The study was quantitative in nature, with a unique group design and evaluations at the beginning and at the end of the therapy. For each patient, the OQ-45.2 was administered at the end of the first, and after the last psychotherapy session. In addition, the IAT-P was administered once, at the fourth session. In order to assess the pre-post psychotherapy differences, a samples-related t test was performed. In addition, a Reliable Change Index was calculated using scores of the first and final OQ-45.2 administration; and finally, the percentage of patients with clinically significant change, was estimated. The administration of the IAT-P showed a restriction of range with positive bias both, on overall total scale scores as well on each subscale score. For this reason, using the median, two subgroups for the overall IAT were created. Also, two subgroups were generated for each subscale: a subgroup of subjects with scores higher than the median and a subgroup of subjects with scores below the median. Then, by using the Mann-Whitney U test, the Reliable Change Index from the groups with high or low levels of alliance were compared. Results of this study showed significant differences between the first and last application of the OQ-45.2. In order to estimate whether the change was clinically significant, cut-off scores and Reliable Change Index were used. In the OQ-45.2 scale, 17 patients left the clinical group, 12 people met the Reliable Change Index criterion, and 8 people showed a clinically significant change. In relation to the closure modality, 7 patients with clinically significant change ended the psychotherapy with a discharge given by the therapist, while one requested the closure of the therapy. Scores from the IAT-P were located in the upper two thirds of the scale. The Bond Subscale had the highest mean, while Tasks and Goals got a slightly lower value. With respect to the main issue, it was found a significant association between therapeutic alliance and the outcome of the psychotherapy both, on overall total scale scores of the OQ-45.2 as well Symptoms Scale of the same instrument. Results showed that the alliance between therapist and the patient especially helped to reduce patient's symptoms. In addition, it was evident that students in training were able to establish good alliance with their patients, and thus to promote the achievement of the therapeutic outcome. These results are discussed taking into account current research on this topic.