The Decisive Moment Making Diagnostic Decisions and Designing Treatments

In this article we describe an investigation into the diagnostic activities of practicing clinical psychologists. Two questionnaires were filled in by 313 psychologists. One group of psychologists (N=175) judged the necessity of diagnostic activities; the other group (N=138) selected the activities they would actually perform. Results show that more participants thought that diagnostic activities were necessary than there were participants who intended to actually perform those activities. Causal analysis, by generating and testing diagnostic hypotheses to form an integrated client model with an explanation for the problem, was judged least necessary and would not be performed. We conclude that a discrepancy exists between the number and kind of activities psychologists judged to be necessary and they intend to actually perform. The lack of attention for causal analysis is remarkable as causal explanations are crucial to effective treatment planning. This chapter has been published as Groenier, M., Pieters, J.M., Hulshof, C.D., Wilhelm, P., & Witteman, C.L.M. (2008). Psychologists’ judgements of diagnostic activities: Deviations from a theoretical model. Clinical Psychology and Psychotherapy, 15, p. 256 265. doi: 10.1002/cpp.587 Psychologists’ Judgements of Diagnostic Activities 21 The goal of psychodiagnosis is to understand the complaints of a client and to provide an indication for their treatment. In the psychodiagnostic process, information about the client’s complaints, problems and environment is gathered in interviews and through tests, until a classifying and explanatory diagnosis is reached and treatment decisions can be made (De Bruyn, Ruijssenaars, Pamijer, & Van Aarle, 2003; Ruiter & Hildebrand, 2006). The goal of the psychodiagnostic process is to form an integrated picture of the client, with a problem description and an explanation for the problem, and to propose a possible treatment for the problem based on this integrated picture. Psychologists may use several methods to collect relevant information, such as diagnostic interviews, tests or questionnaires. The final diagnosis is the result of an integration of the information gathered and the decisions made along the way. Theoretical models have been developed to aid psychologists in organizing and judging the importance of client information. These models usually contain several sequential phases – from describing the problem to selecting a treatment method (De Bruyn et al., 2003; Vertommen, Ter Laak, & Bijttebier, 2005). This paper focuses on the question which diagnostic activities are considered theoretically necessary in diagnosing a client and which would be actually used. As further treatment planning depends on an accurate diagnosis and an effective diagnostic process, research into diagnostic activities can be used to improve both the diagnostic process and the diagnosis. Since Meehl (1954) challenged the value of intuitive clinical judgement, prescriptive methods for collecting and interpreting information in psychodiagnosis have been proposed to counteract the low reliability and validity of diagnostic judgement (Garb, 1998). The central idea of prescriptive psychodiagnostic models such as the Diagnostic Cycle is that psychodiagnosis should adhere to the scientific method to obtain knowledge in psychology by generating and testing hypotheses (De Bruyn et al., 2003). The Diagnostic Cycle prescribes three phases: observations of the client, formulating and testing hypotheses about the problem and possible causes of the problem based on these observations, and an evaluation of the outcomes of testing these hypotheses (Van Aarle & Van den Bercken, 1999). For example, a psychologist may see a child who is easily distracted and at times aggressive. A hypothesis is generated about the origin of the aggressive behaviour and a test is performed showing that the child has limited social abilities. Based on studies that show that limited social abilities may result from deprived sensory stimulation in early development, the psychologist then hypothesizes that the child may have lacked physical contact in her early years. This hypothesis is confirmed by the child’s parents who explain that due to an illness the child had to be physically restrained and was not to be cuddled for a short period after birth. The goal of formulating and testing hypothesized explanations of a client’s problem is to make sure that a plausible explanation is found by explicitly considering and ruling out other possible causes, and consequently a focus in treatment can be selected on a firm foundation (De Bruyn et al., 2003). Identifying causal factors that affect the problem is necessary to plan effective treatment (Haynes & Williams, 2003). Although formulating an explanation for a problem is not always necessary to start treatment, it provides much needed insight to direct treatment if the problem is complex or the first choice treatment method is not working as expected and the intervention needs to be adjusted. The problem with most prescriptive models, including the psychodiagnostic models, is that they are rather time-consuming. They propose strict and lengthy procedures which require a lot of mental effort (Van Aarle & Van den Bercken, 1999). Also, immediate feedback on the hypothesis testing process necessary to improve diagnostic performance is