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Anxiety is a biological response which serves as an essential warning adaption in humans (Rowney & Hermida, 2010). Anxiety can develop into a pathologic disorder when it is triggered excessively and uncontrollably, uncontrollably, requiring no specific stimulus, and manifesting with a variety of physical and affective symptoms altering behaviour and cognition (Davison & Neale, 2005). In the year 2000 the American psychiatric association created a certain category for anxiety disorders in the DSM-IV, this category included the following f ollowing disorders: a) panic disorder without agoraphobia, b) panic disorder di sorder with agoraphobia, c) agoraphobia without a history of panic disorder, d) social phobia, e) generalised anxiety disorder, f) specific phobia, g) posttraumatic stress disorder, h) acute stress disorder, i) obsessive compulsive disorder, j) anxiety disorder due to a general medical condition and k) substance induced anxiety (APA, 2000). For all of the subtypes under this classification it must be acknowledged acknowledged that each condition shares a similar psychological process involving either or both cognitive distortions and automatic negative thoughts (ANT) (Davison & Neale, 2005). Considering the homogeneity of anxiety disorders the recommended treatment is cognitive behavioural therapy (CBT) (Holmes, 2002). Indeed, cognitive behavioural therapy has much positive support due to its apparent efficiency across a number of psychiatric disorders (Holmes, 2002), however the question this paper aims to answer is what exactly is the empirical status of cognitive behavioural therapy? The current paper will firstly firstl y introduce CBT leading on to the t he efficacy of CBT for fo r childhood and adolescent anxiety disorders, following this a review of the empirical evidence supporting adult and older adult treatment using CBT will be outlined with a final note being given to technological extensions of CBT. In the past, behaviour therapy (the ‘BT’ in CBT) advanced adhering to the ph enomena proposed by classical and operant conditioning, however it has continued to progress and evolve incorporating a cognition element due to the recognition that person – person – environment environment interactions are interceded by cognitive processes (Van Hasselt & Hersen, 1993). Nowadays
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purely behavioural therapists work with clients to alter behaviours in order to reduce stressful thoughts and emotions (Compton, March, Brent, Albano, Weersing & Curry, 2004). Contrastingly, cognitive therapists work to modify the initial distressing thoughts and feelings, with improvements in behaviour following simultaneously (Compton et al., 2004). A defining aspect of CBT is that it proposes that symptoms and dysfunctional behaviours are more often cognitively mediated and therefore improvements require the transformation of a negative, dysfunctional thought process into a realistic or positive way of thinking (Dobson & Dozois, 2001). Despite the popular view that CBT is a unitary treatment, CBT actually incorporates an assortment of dense and subtle interventions from the social learning outlook (Compton et al., 2004). CBT involves the development of a case formulation for a client. The CBT case formulation guides the therapist in administering therapy adapting the techniques to suit the patient’s presenting mental issues (Compton et al., 2004). Cognitive behavioural therapy is diverse in its patient base, however, despite the differences in clientele t he intervention method shares five features: 1) Adherence to t he scientist-clinician model, in that treatments are deciphered according to demonstrated evidence. 2) Functional analysis of target behaviours and cognitive distortions which aid the maintenance of t he symptoms. 3) Prominence of psycho-education. 4) Problem specific treatment and 5) relapse prevention (Compton et al., 2004). Particularly with the anxiety disorders category CBT employs techniques such as cognitive restructuring and exposure in order to extinguish inappropriate fears and thoughts (Compton et al., 2004). As a direct result of how structured and scientific this method of therapy is, CBT can be recommended as a reliable approach for paediatric mental illness (Barrett, Duffy, Dadds & Rapee, 2001). Children’s acquisition of socio-emotional abilities develop with time, however the failure to develop such skills at relatively the same pace as matched controls may suggest capacity limitations, a problematic environment or a mental illness (Compton et al., 2004).
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When CBT is applied to child therapy the therapist must gain an in depth understanding of the presenting issues and view the environment of the child to learn of any possible developmental constraints. This information must then be used in the formulation to form a detailed therapeutic strategy with the aim of restoring the child’s level of development to that of their healthy peers (Compton et al, 2004). Children suffering an anxiety disorder often view the world as threatening and respond to their perceived threatening stimuli through avoidance (Compton et al., 2004). Cognitive behavioural therapy for children assists the child to reconceptualise those situations which trigger fear and build a new successful coping template (Barrett, Duffy, Dadds & Rapee, 2001). Treatment for children regularly includes relaxation training, imagery, development of problem solving skills, role play and in-vivo exposure (Compton et al., 2004). It was long thought that CBT was not applicable for children with mental illnesses however Albano and Kendall (2002) i nvestigated the efficacy of CBT for childhood panic disorder and found that this prior view of childhood CBT was incorrect. Findings from this study supported the results revealed by earlier researchers such as Borkovec and Costello (1993) comparing relaxation therapy to CBT for children with generalised anxiety disorder. Overall results showed in favour of CBT as being the most effective method of treatment. Kendall (1994) conducted a randomised clinical trial of cognitive behavioural therapy with anxious children between nine and thirteen years of age. Children selected to participate in the CBT trial received sixteen CBT sessions. An analysis of self-repost measures, parental reports and behavioural observations indicated significant improvements in the children who received CBT in comparison to those who as the control group did not. This experiment followed up the initial findings with a maintenance test one year later. It was discovered that only sixteen sessions of CBT for anxious children sustained the benefits originally gained even after a period of one year post-treatment (Kendall, 1994).
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In 2001 Barrett, Duffy, Dadds and Rapee followed up a study originally started by Barrett, Dadds and Rapee in 1996 in which it was identified that CBT was effective for childhood anxiety problems. The researchers included Fifty two of the original seventy nine children who had received CBT treatment approximately 6.17yrs earlier. The aim of the study was to test the efficacy of CBT in the long-term. Results were impressive revealing that 85.7% were no longer classified as suffering an anxiety disorder thus supporting the idea that CBT is a long-lasting therapeutic method for children (Barrett, Duffy, Dadds & Rapee, 2001). Cognitive behavioural therapy as a form of psychotherapy has been researched at length. In excess of one hundred and twenty controlled clinical studies have been published between 1986 and 1993 with this trend extending each year (Hollon & Beck, 1994). This surge in CBT research is understood to be related to the realisation that CBT is applicable for a wide range of mental disorders (Beck, 1997). CBT for adults diagnosed with an anxiety disorder focuses on modifying thought and transferring learned skills from therapy to the client’s everyday life (Butler, Chapman, Forman & Beck, 2006). CBT makes adults their own therapist in order to alter cognitive distortions (Beck, 1997). The major attribute of CBT which has given this treatment style the edge over other methods is its evident effectiveness in the long-term (Dobson & Dozois, 2001). Borkovec and Costello (1993) compared the long-term effectiveness of CBT and relaxation therapy for generalised anxiety disorder (GAD) in adults. The researchers identified a superior result of 58% of CBT patients no longer meeting criteria for GAD, comparatively relaxation therapy revealed a 38% statistic of those patients no longer within range of a diagnosis of GAD (Borkovec & Costello, 1993). In relation to the successful treatment of panic disorder Gould, Otto and Pollack (1995) conducted a meta-analytic comparison of purely cognitive intervention therapies and CBT using exposure treatment. The CBT approach combining the exposure technique was
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distinguished as the most productive in treating patients with panic disorder. This combination of interventions is the method of choice for CBT practitioners. Oei, Llamas and Devilly (1999) studied the efficacy of CBT for patients suffering panic disorder with agoraphobia comparing their anxiety levels to that of undiagnosed community members. It was discovered that CBT can produce anxiety levels lower than that of the community by the final therapy session and these scores were consistent during a follow up study conducted one year later (Oei, Llamas & Devilly, 1999). Another form of anxiety disorder also linked to social situations is social phobia. DeRubeis and Crits-Cr istoph (1998) reviewed the long-term validity of CBT for this particular disorder and it was concluded that CBT is also an effective therapy for social phobia. Previously in psychology the prevalent method for the treatment of obsessive compulsive disorder (OCD) was simply exposure with response prevention, the ERP of counselling psychology, now however due to the level of support for CBT t here is also growing evidence that CBT incorporating exposure is more effective than exposure treatment alone (Chambless & Ollendick, 2001). This hypothesis was tested by van Balkom, van Oppen, Vermuelen, van Dyck, Nauta and Vorst (1994), the authors concluded that CBT led to substantial reductions in obsessive thoughts and compulsive behaviours. According to patients ratings and clinical assessments CBT showed more impressive results than the more traditional method of simple exposure treatment even at a twelve month follow up report (van Balkom et al., 1994). In 2005 the royal college of psychiatrists and the British psychological society completed a thorough meta-analysis of clinical research to date on posttraumatic stress disorder (PTSD).The patient population reviewed was extensive incorporating backgrounds such as survival from a serious accident, sexual assault, domestic violence, military combat and refugees. CBT was by and large identified as the most effective treatment for PTSD
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(RCP & BPS, 2005). This conclusion was later supported by Hofmann and Smits (2008) comparing CBT in PTSD patients to a placebo controlled trial. Despite impressive advances observed for CBT since it first emerged in the 1980’s not a lot of attention has been focused on treating anxiety disorders in the older adult (Beck & Stanley, 1997). According to Flint (1994) the prevalence of anxiety disorders in the elderly is considerably lower than that of the younger population. Lawton, Kleban and Dean (1993) provide an explanation for this by asserting that the nature of anxiety is different in older adults. In their study the researchers included two hundred and seven young adults, two hundred and thirty one middle aged adults, and eight hundred and twenty eight older adults. The aim of the study was to compare the varying age groups on response to affect terms. The results revealed that elderly participants reported less of most of the negative emotional states particularly anxiety. Regardless of the reduction in prevalence of anxiety disorders among the elderly Regier, Boyd, Burke, Rae, Myers and Kramer (1988) report that GAD in older adults is as prevalent as major depression and that in general anxiety disorders are more of an issue among the elderly than mood disorders. However, the question remains, can CBT benefit the elderly who do suffer some form of anxiety disorder? Older people consume a large share of anti-anxiety medications which in itself suggests that anxiety is an issue worth addressing in the elderly population (Graham & Vidal-Zeballos, 1998). Anxiolytic pills including benzodiazepines are among the most common medications provided to the elderly for the treatment of anxiety (Blazer, George & Hughes, 1991). However, the major issue with this method of treatment involves the risk of cognitive impairment which is linked to these medications (Blazer, George & Hughes, 1991). This calls for a new more acceptable way of treating anxiety disorders in the elderly. In the year 2001 Barrowclough, King, Colville, Russell, Burns and Tarrier found that home delivered CBT for the elderly suffering GAD was more effective than supportive
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counselling. This method also allowed the patient to relax as the therapy was carried out in the comfort of their own home. Wetherell, Gatz and Craske (2003) conducted another study to test the value of CBT for GAD in an elderly patient base. CBT was compared to a discussion group and a waiting period group. There were a total of seventy five participants, averaging in age at sixty seven years. Participants in both the CBT and discussion group showed benefits over the waiting period group, however in a long-term follow up of twelve months CBT showed stronger lasting effects (Wetherall, Gatz & Craske, 2003). This suggests that the empirically supported hypothesis that CBT acts as a sound alternative to medication for the elderly suffering from anxiety disorders can with future research gain even more appreciation. Another less well highlighted area within cognitive behavioural therapy is its apparent effectiveness in the treatment of anxiety disorders following traumatic brain injury (TBI) (Williams, Evan & Fleminger, 2003). Williams, Evan and Fleminger (2003) studied patient ‘DC’ who acquired TBI subsequent to a serious accident. DC suffered amnesia, attention difficulties and self-doubt as a result which manifested as OCD. DC’s self -doubt stemmed from his amnesia which likely caused him to develop obsessive thoughts and checking compulsions. DC developed a maladaptive coping strategy of avoidance behaviours involving avoiding social situations. Anxiety disorders are thought to be quite common in TBI patients however, the difficulty in distinguishing an anxiety disorder from other impairment consequences often leads to an overlook of the problem (Williams, Evan & Fleminger, 2003). It must also be considered that chronic anxiety in a patient has been shown to produce neurotoxins decreasing the size of the hippocampi through cell atrophy (Bremner, Randall, Scott, Bronen, Seibyl, Southwick, Delaney, McCarthy & Charney, 1995). CBT as previously expressed by this paper has been regarded as a highly effective method of treating anxiety disorders. A combination of CR (cognitive rehabilitation) and CBT has been
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emphasised as the appropriate measure for treating anxiety disorders in neurologically impaired individuals (Williams, Evan & Fleminger, 2003). Cognitive behavioural therapy applied to the case of ‘DC’ involved exposure, response prevention and m anagement of automatic negative thoughts which maintained his self-doubt. Overall the t reatment for DC which comprised of CBT reduced significantly DC’s automatic negative thoughts allowing him to build his self-esteem. Exposure treatment helped reduce the obsessions and compulsions which accompanied DC’s OCD (Williams, Evan & Fleminger, 2003). Thus far this paper has not considered medication in direct competition with CBT, the efficacy of imipramine versus CBT for panic disorder in adults will now be discussed. Barlow, Gorman, Shear & Wood (2000) identified a lifetime prevalence for panic disorder of approximately three percent. The researchers questioned whether medication, CBT or a combination of both would aid the recovery from panic disorder. Randomised, double blind, placebo controlled trials were created in four major anxiety research clinics following three hundred and twelve patients over a seven year period. Eighty three patients were randomly assigned to the imipramine study. Seventy seven patients were selected at random for the CBT study. Twenty four patients were assigned to the placebo only study. Sixty five patients were allocated to the CBT plus imipramine study while the remaining sixty three took part in the CBT plus placebo study. The combination of imipramine and CBT revealed the most impressive results. CBT alone and imipramine alone showed equal efficiency in the twelve month follow up study (Barlow, Gorman, Shear & Woods, 2000). Finally the current paper will consider some of the technological tools which have been manufactured in recent years to aid the efficacy of CBT. Newman, Consoli and Taylor (1999) describe the Palmtop computer program developed for the treatment of GAD. According to the authors, identified advantages of this program include continuous, unobtrusive collection of process data on treatment adherence, therap y in the patient’s natural
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setting, therapy beyond the set hour with a therapist and the insurance of homework completion. Palmtops allow repeated assessment and the program has been created to cater for specific responses modifying the therapy given depending on the situation presented. The device has been programmed to provide cognitive restructuring, exposure, relaxation training, breathing retraining, and positive imagery (Newman, Consoli & Taylor, 1999). Newman, Kenardy, Herman and Taylor (1997) reported that from their studies involving patients Miss Q, Mr. J and Mr. K the use of palmtop computers as an extension of CBT in conjunction with normal CBT therapist applied therapy was even more beneficial than CBT alone. CBT is particularly well suited for technological aid as it is well described, structured and specific (Anderson, Jacobs & Rathbaum, 2004). Virtual reality therapy is another form of exposure utilised by CBT particularly for those suffering agoraphobia as they must overcome their fear of leaving their home environment (Anderson, Jacobs & Rathbaum, 2004). Virtual environments afford the client the opportunity to participate in the environment in which they feel anxious however, this environment is completely controlled by the therapist, t his allows the exposure to be graded according to the exact requirements of the patient (Pull, 2005). Rothbaum, Hodges, Ready, Graap and Alarcan (2001) utilised virtual reality exposure treatment in conjunction with CBT for PTSD in Vietnam veterans. This overcame the inability to ethically create in-vivo exposure and produced gains significant at the six month follow up period. In 2002 Emmelkamp, Krijn, Holsbosch, de Vries, Schuemie and van der Mast (2002) compared the relative efficacy of in-vivo exposure and virtual reality exposure for a specific phobia, the fear of heights. Results showed that virtual reality exposure was as efficient as in-vivo exposure for reducing anxiety and avoidance behaviours (Emmelkamp et al., 2002). This paper has considered the relative efficacy of cognitive behavioural therapy for children, adults, the elderly and neurologically impaired patients suffering from anxiety
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disorders. Each of the patient groups were provided with satisfactory empirical evidence further revealing the adaptive and successful nature of t his therapeutic method. The key to the success shown by CBT is its incorporation of the classic behavioural technique and the more modern cognitive treatment measure (Holmes, 2002). As a result of the research noted in this paper it can be concluded that cognitive behavioural therapy does in fact have an empirically supported evidence base which is even more concentrated when combined with a technological device such as the palmtop computer or virtual reality therapy.
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