How effective have cognitive behavioral therapy type techniques been shown and proven to work for anxiety based on published literature?
Meta-analyses are usually pretty accurate, as they essentially bring together the data from many studies that investigate the same topic of interest together and use statistical methods to effectively get the most conclusive answer possible, throughout all of the studies assessed, just HOW effective is a certain treatment?
For your specific question, there's one in particular that strongly supports CBT for anxiety. It looks at 71 different studies (that's a ton). It also investigates it's effectiveness in a variety of different environments and versions of it's therapy. It was even published only last month.
Clin Psychol Rev. 2013 Jul 20;33(8):954-964. doi: 10.1016/j.cpr.2013.07.003.
A meta-analysis of nonrandomized effectiveness studies on outpatient cognitive behavioral therapy for adult anxiety disorders.
Hans E, Hiller W. Source Department of Clinical Psychology, Johannes Gutenberg University Mainz, Germany.
Electronic address: [email protected]
OBJECTIVE: The primary aim of this study was to assess the overall effectiveness of individual and group outpatient cognitive behavioral therapy (CBT) for adults with a primary anxiety disorder in routine clinical practice.
METHOD: We conducted a random effects meta-analysis of 71 nonrandomized effectiveness studies on outpatient individual and group CBT for adult anxiety disorders. Standardized mean gain effect sizes pre- to posttreatment, and posttreatment to follow-up are reported for disorder-specific symptoms, depression, and general anxiety. The mean dropout from CBT is reported.
RESULTS: Outpatient CBT was effective in reducing disorder-specific symptoms in completer (d=0.90-1.91) and intention-to-treat samples (d=0.67-1.45). Moderate to large (d=0.54-1.09) and small to large effect sizes (d=0.42-0.97) were found for depressive and general anxiety symptoms posttreatment. Across all anxiety disorders, the weighted mean dropout rate was 15.06%. Posttreatment gains for disorder-specific anxiety were maintained 12months after completion of therapy.
CONCLUSIONS: ****CBT for adult anxiety disorders is very effective and widely accepted in routine practice settings.**** However, the methodological and reporting quality of nonrandomized effectiveness studies must be improved. © 2013.
Across 71 studies, the conclusion used the word "very effective," which is very rare to see in any study in the conclusions section, especially a meta-analysis, the weighted mean dropout rate across all different types of its application was only 15.06%, AND gains were generally maintained for 12 months (maybe more, I don't have full text) after beginning therapy.
The only caveat they mention is that the methodology and reporting quality must be improved, but I feel that's a general trait that almost all studies need improvement in.
Plus when you investigate SEVENTY-ONE (71) studies, statistical laws start to take over anyway.
Based on this, I'd have to say that there is very, very strong evidence that Cognitive Behavioral Therapy is an effective treatment for anxiety disorders.
In my opinion, and as an analogy, it's almost just as if not more proven than using aspirin or acetaminophen to relieve a simple headache. It just works according to the literature, which, if you have that many studies then "routine clinical analysis" really does become reality. More and more clinical psychologists are switching over to this method or attempting to make some sort of derivative of it.
Frankly, I don't see how the meta-analysis of 70-something non-randomized studies from the self-accepted answer is such amazing evidence. On the other hand, there's a 2008 meta-analysis of just the randomized (and double-blind) studies (RCTs), and these are not so few either:
We included studies that randomly assigned adult patients meeting DSM-III-R or DSM-IV criteria for an anxiety disorder to either CBT or placebo. Of 1,165 studies that were initially identified, 27 met all inclusion criteria. [… ]
Random effect models of completer samples yielded a pooled effect size (Hedges' g) of 0.73 (95% confidence interval, 0.88-1.65) for continuous anxiety severity measures and 0.45 (90% confidence interval, 0.25-0.65) for depressive symptom severity measures. The pooled odds ratio for completer treatment response rates was 4.06 (95% confidence interval, 2.78-5.92). The strongest effect sizes were observed for obsessive-compulsive disorder and acute stress disorder. The advantage of CBT over placebo did not depend on placebo modality, number of sessions, or study year.
Our review of randomized placebo-controlled trials indicates that CBT is efficacious for adult anxiety disorders.
The notion of placebo is however not always clear when it comes to psychtherapy; in this meta-analysis it
had to involve interventions to control for nonspecific factors (e.g., regular contact with a therapist, reasonable rationale for the intervention, discussions of the psychological problem). Placebo interventions that included active treatment ingredients for the target problem (e.g., an intervention that specifically instructs participants to engage in exposure exercises to test certain predictions or to challenge a maladaptive thinking style) were not included
Also only double-blind studies were included in these 27:
(c) Participants and evaluators were blinded to treatment condition (i.e., participants and evaluators were not aware whether they received active treatment or placebo intervention); (d) The evaluators were blinded to treatment conditions (i.e., evaluators were not aware which treatment condition participants had received; and (e) the description of drop-outs was provided.
There's even a newer (2018) meta-analysis of the same kind
The purpose of this study was to examine the efficacy of cognitive behavioral therapy (CBT) for anxiety-related disorders based on randomized placebo-controlled trials. We included 41 studies that randomly assigned patients (N = 2,843) with acute stress disorder, generalized anxiety disorder (GAD), obsessive compulsive disorder (OCD), panic disorder (PD), posttraumatic stress disorder (PTSD), or social anxiety disorder (SAD) to CBT or a psychological or pill placebo condition. Findings demonstrated moderate placebo-controlled effects of CBT on target disorder symptoms (Hedges' g = 0.56), and small to moderate effects on other anxiety symptoms (Hedges' g = 0.38), depression (Hedges' g = 0.31), and quality of life (Hedges' g = 0.30). Response rates in CBT compared to placebo were associated with an odds ratio of 2.97. Effects on the target disorder were significantly stronger for completer samples than intent-to-treat samples, and for individuals compared to group CBT in SAD and PTSD studies. Large effect sizes were found for OCD, GAD, and acute stress disorder, and small to moderate effect sizes were found for PTSD, SAD, and PD. In PTSD studies, dropout rates were greater in CBT (29.0%) compared to placebo (17.2%), but no difference in dropout was found across other disorders. Interventions primarily using exposure strategies had larger effect sizes than those using cognitive or cognitive and behavioral techniques, though this difference did not reach significance. Findings demonstrate that CBT is a moderately efficacious treatment for anxiety disorders when compared to placebo. More effective treatments are especially needed for PTSD, SAD, and PD.
Since this 2018 meta-analysis presented itself as the successor of the one a decade before (it shares some authors as well) it still included OCD, acute stress disorder, and PTSD even though these are no longer classified as anxiety disorders in DSM-5.
It's also interesting that there few RCTs of CBT in GAD though (only 2).
Also RCTs aren't all the same quality-wise…
the strength of the effect of CBT depended on whether the analysis was conducted on completer or ITT [intent-to-treat] samples, with completer samples producing significantly larger effect sizes, though not ORs [odd ratios], compared to ITT samples. Such a discrepancy between ITT and completer samples is particularly important given that CBT was associated with significantly greater dropout rates than placebo in the present analysis, a result not found in Hofmann and Smits (2008). Notably, this result appeared to be driven by greater dropout rates among CBT patients in PTSD studies, which has also been found in previous meta-analytic research (Imel, Laska, Jakupcak, & Simpson, 2013). Such a finding suggests that for PTSD studies, the superior effect of CBT compared to placebo may be inflated by lack of data from dropouts.
[… ] only 16 of the 41 studies included used ITT analyses, and the use of completer analyses appeared to lead to greater effect size estimates. Even among studies using ITT analyses, results from our risk of bias assessment indicated that many studies did not account for missing data properly, or did not provide adequate information for why data were missing or how missing data were dealt with. Relatedly, the present results may have been influenced by publication bias. In addition, criteria for treatment response varied between studies, potentially contributed to increased heterogeneity in the effect sizes for categorical outcomes.
They also note that meta-analyses using only waitlists as opposed to more active placebos had reported even greater effect sizes:
For instance, the metaanalysis by Bandelow et al. (2015) comparing CBT to waitlist produced an overall effect size of 1.23 for anxiety disorder symptoms. In contrast, we observed that CBT was associated with an effect size of 0.56 when compared to placebo.
The metaanalysis of Bandelow et al. is also interesting in its own ways; although it targeted fewer disorders (I think they adopted to the DSM-5 view) namely only Panic disorder/agoraphobia, GAD and Social anxiety disorder, it compared treatments multiple treatments, with some interesting conclusions:
In direct comparisons, individual CBT/exposure was significantly more effective than waiting list, psychological placebo and pill placebo conditions (Table 3). Group CBT was superior to waiting list, but not to pill placebo. Relaxation and non-face-to-face therapies were superior to waiting lists.
In that last table, "Fail-safe N" (number of negative studies needed to reject the hypothesis that a treatment differs from a control group) and "Egger P" estimate publication bias; the "adjusted d" is using the publication-bias-correcting 'trim and fill' method of Duval and Tweedie (2000). (Alas the meta-analyses of Hofmann and Smits did not report something like this.)
Cognitive–Behavioral Therapy for Clients With Anxiety and Panic
In Cognitive–Behavioral Therapy for Clients With Anxiety and Panic, Bunmi O. Olatunji demonstrates this effective and versatile approach to helping clients meaningfully change detrimental patterns in their thoughts and actions.
Cognitive–behavioral therapy views anxiety as the result of maladaptive habits of thinking and behavior, usually including the tendency to overestimate the possibility of something negative occurring and to avoid that which produces anxiety. Studies have found that avoidance temporarily eases fear, but tends also to reinforce it so that it continues over time. To counter this, the therapist often will teach new ways of thinking and gradually expose the client to that which causes anxiety.
In this session, Olatunji works with a young woman who is suffering from panic attacks. First he provides some psychoeducation about the purpose of fear and anxiety, and then helps her to see the irrational aspects of the rationalizations she makes for feeling the way she does.
Cognitive–behavioral therapy (CBT) is a set of treatment techniques that view the client as an active participant in his or her own treatment. It is seen as beneficial if the patient understands exactly what is involved in treatment, and the ideas behind why these particular treatment techniques are used.
The techniques used in CBT have been tested in numerous studies with people who suffer from anxiety disorders. The results of these studies show that CBT is very effective in reducing anxiety-related problems. In fact, CBT is generally considered the gold-standard treatment for the anxiety disorders.
CBT is based on the notion that anxiety problems involve maladaptive patterns of thinking and behavior. Thinking patterns in anxiety usually include the tendency to overestimate the probability and severity of negative outcomes. This type of thinking leads to feelings of anxiety.
Behavioral patterns in anxiety disorders largely include avoidance and other anxiety-reduction strategies ("safety behaviors"). These behaviors serve as an escape from anxious situations, yet they also prevent the person from learning that these situations are not nearly as dangerous as they had thought. Therefore, the person gets stuck performing the maladaptive behaviors which maintain their fears.
In CBT, the patient is taught to systematically expose oneself to the situations they are avoiding. This provides an opportunity for the person to learn new ways of thinking and behaving in situations which create anxiety so that he or she can accept that such situations are not dangerous.
Bunmi O. Olatunji, PhD, is an assistant professor in the Department of Psychology and Psychiatry at Vanderbilt University in Nashville, Tennessee.
He is associate editor of Journal of Experimental Psychopathology and currently serves on the editorial boards of the journals Behavior Therapy, International Journal of Cognitive Therapy, and Journal of Anxiety Disorders. He has published more than 100 journal articles and book chapters and has participated in more than 100 conference presentations. He is coeditor (with Dean McKay) of Disgust and Its Disorders: Theory, Assessment, and Treatment Implications, a volume on the role of disgust in psychological disorders recently published by APA. He is also guest editor of a special issue on cognitive–behavioral therapy that was recently published in Psychiatric Clinics of North America.
As director of the Emotion and Anxiety Research Laboratory at Vanderbilt University, he is currently examining the role of basic emotions as they relate to the assessment, etiology, and maintenance of anxiety-related disorders. His research has been funded by the National Institutes of Health and the Anxiety Disorders Association of America. His research on the role of disgust in anxiety disorders has also been recognized by APA.
He is a member of the Health Anxiety Workgroup and is director and founder of the Vanderbilt Adult Anxiety Clinic, a treatment and research facility in Nashville, Tennessee.
The effect of cognitive behavioral therapy
A new study shows that Cognitive Behavioral Therapy (CBT) is effective in treating general anxiety disorder and the way the brain processes anxiety.
Has anyone ever told you that your anxiety is just "all in your head?" People with anxiety are told this time and time again&mdashthat if they just relax, they wouldn't suffer from constant worries or fears. But if this is true, why are so many people still struggling with anxiety? Research has found that diagnosed anxiety isn't quite "all in your head" in the traditional sense. In fact, for those with generalized anxiety disorder (GAD), it's all in the brain and the way the brain functions. This means that people with GAD experience anxiety due to biological differences in their brains that are distinct from the average person.
Can We Change how the Brain Works?
There currently exist effective treatments for GAD, such as medications and a form of psychotherapy known as Cognitive Behavioral Therapy, or CBT. CBT is a form of psychotherapy that focuses on changing thoughts, interpretations of experiences, and behaviors to promote reductions in anxiety. Yet, the big question remains: can these treatments alter the way our brains function? For those who prefer therapy over medication, this sets up a huge challenge. Can an hour in a therapist's office every week make a dent in the way the brain experiences anxiety?
This was the dilemma that my colleagues and I set out to resolve. We wanted to see if CBT would be effective in altering the very function of the brain in adults with GAD.
Is Talking it out Enough?
To test this we examined the brains of 21 adults with GAD and a control group of adults without GAD. We had both groups complete a face processing paradigm, which is a trial in which participants are exposed to faces on a screen expressing different emotions such as fear, anger, and happiness. In our study, the participants' brain reactions to these emotional faces were scanned and assessed both before and following CBT treatment.
We found that those who received CBT treatment showed different brain responses when performing this task than those who did not. More specifically, we found that CBT weakened responses to fearful and angry (threat-conveying) faces in a region of the brain known to be hyperactive in those with anxiety to stimuli in the environment that signal a potential threat&mdasha change that was not observed in the control participants. This means that therapy does, in fact, have the capability to affect anxiety on a biological level, which is consistent with the clinical knowledge that therapy and medications are both effective treatments for GAD.
The Impact of CBT
So how is this relevant to the average person suffering from anxiety? First off, it's helpful to realize that your worries or fears are not just "all in your head"&mdashat least not purely in the conventional sense of the phrase. There's a biological reason that you are feeling what you are feeling, and unfortunately it's not something that can be switched on and off at will. We don't yet know why one's brain functions differently in those with anxiety, but there's good evidence that genetics, environmental upbringing, and current stress levels can all play an important part.
The findings from our study tell us that people with GAD have the ability to make an impact on the very biology that might be driving their fear and anxiety. In collaboration with a trained and experienced mental health professional, it is possible to recover from generalized anxiety disorder or any other type of extreme anxiety. We have treatments that work, and the field of science is finally starting to recognize that exploring moods, emotions, and personal events through therapy can really make an impact. Cognitive Behavioral Therapy can help change the way you feel about things that would otherwise make you anxious&mdashand your brain will follow suit.
Literature search flow
The literature search flow is displayed in Figure 1. In total, 1269 records were identified. After duplicates were removed, 815 studies were screened at ‘abstract’ level. After abstract screening, 91 studies were assessed for eligibility at ‘full-text’ level. Twenty-nine studies were included in the review and these were categorized into three separate meta-analyses (i) CBT compared with no primary care treatment (k = 7) (ii) CBT compared with primary care treatment-as-usual (TAU) (k = 14) and (iii) CBT in addition to primary care TAU compared with primary care TAU (k = 9). The experimental conditions of one study ( 11) facilitated its inclusion in both the second and third meta-analyses.
Is Cognitive Behavioral Therapy as Effective as Clinicians Believe?
For nearly 50 years, cognitive behavioral therapy (CBT) has claimed higher scientific authority among the vast legion of psychotherapy approaches as a result of having more research demonstrate its effectiveness than any other therapeutic method. Increasingly, that track record of empirical evidence has been acknowledged and even translated into government funders and insurance companies requiring therapists to use CBT if they want to be reimbursed. But recent developments have raised questions about whether the effectiveness and scientific bona fides of CBT have been overstated.
Developed largely within university settings concerned with quantifiable research results, CBT has been the focus of far more studies than any other therapy model. Almost 90 percent of the approaches deemed empirically supported by the American Psychological Association’s Division 12 Task Force on Psychological Interventions involve cognitive behavioral treatments. More than 269 meta-analyses have been conducted on CBT, and a 2008 survey by a team of Boston University researchers identified 1,165 CBT outcome studies with a wide range of clients, including those suffering from depression, bipolar disorder, eating disorders, criminal behavior, and chronic pain and fatigue.
But recent findings about the effectiveness of CBT have made waves among psychotherapy outcome researchers. A 2013 meta-analysis published in Clinical Psychology Review comparing CBT to other therapies reported that it had failed to “provide corroborative evidence for the conjecture that CBT is superior to bona fide non-CBT treatments.” In November 2014, an 8-week clinical study conducted by Sweden’s Lund University concluded that CBT was no more effective than mindfulness-based therapy for those suffering from depression and anxiety.
The latest blow to CBT’s claims to therapeutic supremacy came with the publication this past May of a meta-analysis conducted by psychologists Tom Johnsen, of UiT, the Arctic University of Norway, and Oddgeir Friborg, of the University of Tromso, titled “The Effects of Cognitive Behavioral Therapy as an Anti-Depressive Treatment Is [sic] Falling.” Published in the APA’s Psychological Bulletin, the study tracked 70 CBT outcome studies conducted between 1977 and 2014---between the heyday of CBT founders Aaron Beck and Albert Ellis and the most recent studies. Johnsen and Friborg concluded that “the effects of CBT have declined linearly and steadily since its introduction, as measured by patients’ self-reports, clinicians’ ratings, and rates of remission.” According to Johnsen, even the rosy quantitative findings about CBT in its early days should be taken with a grain of salt. “Just seeing a decrease in symptoms,” he says, “doesn’t translate into greater wellbeing.”
Trying to explain the reason for the decline, Johnsen and Friborg suggest that an important factor is the differences among the varying forms of CBT being used in the studies over the years. Today, they argue, there exist two types of CBT: the “pure” CBT, created by Beck and Ellis, reflecting the protocol-driven, highly goal-oriented, more standardized approach they first popularized, in contrast with the looser, more integrative approach of modern CBT. Newer approaches, they believe, often stray from CBT’s original tenets, which included explicitly outlining the treatment agenda at the start of therapy, regularly soliciting client feedback, and including homework assignments after every session. According to Johnsen and Friborg, “Proper training, considerable practice, and competent supervision are very important to provide CBT in an efficacious manner. Therapists who frequently depart from the [Beck] manual demonstrate poorer treatment effects than therapists who follow it.”
Another hit to CBT’s reputation came in 2012 from Sweden’s National Board of Health and Welfare, which, after placing CBT at the top of a list of recommended treatments for depression and anxiety, concluded after a two-year trial period that CBT had no noticeable advantage over alternative therapies and that increasing numbers of clients were dropping out of treatment after finding it ineffective. By that time, more than two billion Swedish kronor had been spent in financial incentives to therapists who made CBT their preferred mode of treatment.
Scott Miller---a psychologist who runs the International Center for Clinical Excellence and spent time in Sweden during the period when the National Board of Health and Welfare was trying to incentivize practitioners to use CBT---believes that the fundamental problem had less to do with CBT itself than with a misguided notion about the factors that make psychotherapy effective. “Our field struggles with the notion that treatments work like medicine,” says Miller. “It’s as if people coming to therapy have a variety of infections that different psychotherapy models will attack like antibiotics. But the truth is that there isn’t any evidence that one therapeutic method achieves better results than any other.”
Some critics of the method have jumped at the recent negative findings to argue that alternative therapies are just as effective as CBT, or even better, but its supporters argue that plenty of reasons to question those findings remain. Steve Hollon, a psychologist at Vanderbilt University who specializes in treating depression, argues that, because conditions of replicated trials can be so wildly different from original ones, it’s unsurprising that results, too, can differ. He agrees with Johnsen and Friborg that studies conducted under Beck’s supervision, for instance, might have been more concerned with methodological fidelity. “It may be that the more recent studies don’t have the same methodological rigor,” Hollon says. “It may be that we’re just seeing the more variable results you’re going to get in the real world.”
As much as we’d like research to provide tidy conclusions and confer legitimacy on our preferred treatment methods, it often just adds to our questions about how to understand what goes on in the consulting room. But in the end, both CBT’s advocates and its critics can agree on two things: no form of psychotherapy offers a reliable miracle cure, and it’s never easy making neat science out of the often nebulous encounter we call psychotherapy.
This blog is excerpted from “Has CBT Lost Its Mojo?" Want to read more articles like this? Subscribe to Psychotherapy Networker Today!
So how effective is Cognitive Behavioral Therapy (CBT)?
In a 2006 paper published in the journal Clinical Psychology Review , researchers found that Cognitive Behavioral Therapy (CBT) “is highly effective for adult unipolar depression, adolescent unipolar depression, generalized anxiety disorder, panic disorder with or without agoraphobia, social phobia, PTSD, and childhood depressive and anxiety disorders,” “is associated with large improvements in symptoms for bulimia nervosa” (with better results than those found using pharmacotherapy, the study adds) and “has shown promising results as an adjunct to pharmacotherapy in the treatment of schizophrenia.”
But that’s not all: CBT was found to be moderately effective in treating “marital distress, anger, childhood somatic disorders and several chronic pain variables (i.e., pain expression behavior, activity level, social role functioning and cognitive coping and appraisal),” and was even “somewhat superior to antidepressants in the treatment of adult unipolar depression.” Even more importantly: The benefits of CBT “are maintained for substantial periods beyond the cessation of treatment. More specifically, significant evidence for long-term effectiveness was found for depression, generalized anxiety, panic, social phobia, OCD, sexual offending, schizophrenia and childhood internalizing disorders.”
In addition, numerous studies have shown CBT to be effective in drug and alcohol treatment settings. In a 2011 article for the peer review journal JAMA Psychiatry , researchers concluded “Providing group cognitive behavioral therapy for depression to clients with persistent depressive symptoms receiving residential substance abuse treatment is associated with improved depression and substance use outcomes. These results provide support for a new model of integrated care.” Even the National Institute on Drug Abuse recognizes the value of CBT in addiction treatment : “Research indicates that the skills individuals learn through cognitive-behavioral approaches remain after the completion of treatment. Current research focuses on how to produce even more powerful effects by combining CBT with medications for drug abuse and with other types of behavioral therapies.”
Such scientific studies on the effectiveness of CBT give it an important distinction: It’s a psychotherapeutic tool that’s evidence-based, which should be a hallmark of any successful treatment protocol. According to a 2017 article in the journal Neurotherapeutics , “By incorporating research into clinical practice, providers use research-driven evidence rather than rely solely on personal opinion … incorporating research inevitably promotes the development of guidelines, databases, and other clinical tools that can help clinicians make critical treatment decisions.”
In other words: Evidence-based therapies are guided by more rigorous, peer-reviewed standards, are implemented based on acceptable and ethical practices and contribute to the trust in an organization’s overall standard of care. When included as part of a comprehensive treatment modality for alcoholism and addiction, it can be extremely effective — for dealing with the issues surrounding the substances, and those with which the substances have been used to cope.
Selection and inclusion of trials
After examining a total of 26,775 abstracts (19,580 after removal of duplicates), we retrieved 2,957 full-text papers for further consideration. We excluded 2,813 of the retrieved papers. The PRISMA flow chart describing the inclusion process and the reasons for exclusion is presented in Figure 1. A total of 144 trials met inclusion criteria for this meta-analysis: 54 on MDD, 24 on GAD, 30 on PAD, and 36 on SAD.
Flow chart of inclusion of trials. MDD – major depression, GAD – generalized anxiety disorder, PAD – panic disorder, SAD – social anxiety disorder, CBT – cognitive behavior therapy
Characteristics of included trials
The 144 trials included a total of 184 comparisons between CBT and a control condition (63 comparisons for MDD, 31 for GAD, 42 for PAD, and 48 for SAD). A total of 11,030 patients were enrolled (6,229 in the CBT groups, 2,469 in the waiting list control groups, 1,823 in the care-as-usual groups and 509 in the pill placebo groups). A total of 113 trials were aimed at adults in general and 31 at other more specific target groups. Eighty trials recruited patients (also) from the community, 51 recruited exclusively from clinical populations, and 13 used other recruitment methods. Sixty-seven trials were conducted in North America, 14 in the UK, 36 in other European countries, 15 in Australia, 4 in East Asia, and 8 in other geographic areas. Of all included trials, 44 (30.6%) were conducted in 2010 or later.
CBT was delivered in individual format in 87 comparisons, in group format in 53, in guided self-help format in 35, and in a mixed or another format in 9. The number of treatment sessions ranged from one to 25.
Sixty trials reported an adequate sequence generation, while the other 84 did not. A total of 46 trials reported allocation to conditions by an independent (third) party. Seventy trials reported blinding of outcome assessors and 57 conducted intention-to-treat analyses. Only 25 trials (17.4%) met all four quality criteria, 62 met two or three criteria, and the remaining 57 met one or none of the criteria. Of the trials conducted in 2010 or later, 29.5% were rated as high-quality, compared to 12.0% of the older studies.
Effects of CBT on MDD
The pooled effect size of the 63 comparisons between CBT and control conditions in MDD 41-94 was g=0.75 (95% CI: 0.64-0.87), with high heterogeneity (I 2 =71). This effect size corresponds to a NNT of 3.86. Studies using a waiting list control group had significantly (p=0.002) larger effect sizes (g=0.98 95% CI: 0.80-1.17) than those using care-as-usual (g=0.60 95% CI: 0.45-0.75) and pill placebo control groups (g=0.55 95% CI: 0.28-0.81) (Table 1 and Figure 2).
Effects of cognitive behavior therapy (CBT) for major depression compared to control conditions: forest plot. BA – behavioral activation, CT – cognitive therapy, in-p – in person, tel – telephone, MBCT – mindfulness based CBT, RCBT – religious CBT, SCBT – secular CBT, iCBT – Internet-delivered CBT, techn – supported by a technician, clin – supported by a clinician, e-mail – supervised by e-mail, gsh – guided self-help format, BIB – bibliotherapy, COP – coping, cCBT – computerized CBT
|N||g||95% CI||p||I 2||95% CI||p||NNT|
|All control conditions||All studies||63||0.75||0.64-0.87||<0.001||71||62-77||3.86|
|Adjusted for publication bias||71||0.65||0.53-0.78||76||69-80||4.55|
|Type of control||Waiting list||28||0.98||0.80-1.17||<0.001||68||50-77||0.002||2.85|
|High-quality studies||Waiting list||6||0.93||0.49-1.37||<0.001||82||56-90||0.06||3.02|
|All control conditions||All studies||31||0.80||0.67-0.93||<0.001||33||0-56||3.58|
|Adjusted for publication bias||42||0.59||0.44-0.75||62||44-72||5.08|
|Type of control||Waiting list||24||0.85||0.72-0.99||<0.001||13||0-47||<0.001||3.35|
|High-quality studies||Waiting list||8||0.88||0.67-1.10||<0.001||33||0-69||0.05||3.22|
|All control conditions||All studies||42||0.81||0.59-1.04||<0.001||77||69-82||3.53|
|Type of control||Waiting list||33||0.96||0.70-1.23||<0.001||77||67-82||<0.001||2.92|
|Care-as-usual||4||0.27||−0.12 to 0.65||0.17||31||0-77||12.25|
|High-quality studies||Waiting list||4||0.61||0.27-0.96||0.001||26||0-75||4.89|
|All control conditions||All studies||48||0.88||0.74-1.03||<0.001||64||50-73||3.22|
|Type of control||Waiting list||40||0.98||0.83-1.14||<0.001||64||47-73||<0.001||2.85|
|High-quality studies||Waiting list||5||1.00||0.61-1.40||<0.001||71||0-87||0.03||2.79|
|Care as usual||2||0.30||−0.04 to 0.64||0.08||0||10.91|
Only 11 of the 63 studies were rated as being high-quality. The effect size in these studies was similar to that in the total pool (g=0.73 95% CI: 0.46-1.00 I 2 =78). No high-quality study used a pill placebo control group. The difference between waiting list and care-as-usual among the high-quality studies was not significant (p=0.06), but this may be related to the small number of those studies.
Egger's test indicated considerable asymmetry of the funnel plot (intercept: 1.54 95% CI: 0.59-2.50 p=0.001). Duval and Tweedie's trim and fill procedure also indicated considerable publication bias (number of imputed studies: 8 adjusted effect size: g=0.65 95% CI: 0.53-0.78 I 2 =76). For high-quality studies, no indication for publication bias was found (but this may again be related to the small number of those studies).
Effects of CBT on GAD
The pooled effect size of the 31 comparisons between CBT and control conditions in GAD 95-117 was g=0.80 (95% CI: 0.67-0.93 NNT=3.58), with low to moderate heterogeneity (I 2 =33) (Table 1 and Figure 3). The vast majority of studies (24 of 31) used a waiting list control group. Studies using a pill placebo control group (g=1.32) had a significantly (p<0.001) larger effect than those using a waiting list (g=0.85) or care-as-usual control group (g=0.45). The number of studies using pill placebo (N=3) and care-as-usual control groups (N=4) was very small, however (Table 1 and Figure 3).
Effects of cognitive behavior therapy (CBT) for generalized anxiety disorder compared to control conditions: forest plot. RELAX – relaxation, BT – behavior therapy, WO – worry exposure, EN CBT – enhanced CBT, iCBT – Internet-delivered CBT, techn – technician assistance, clin – clinician assistance, clin supp – supported by a clinician, lay – lay provider, MCT – metacognitive therapy, IUT – intolerance-of-uncertainty therapy, CT – cognitive therapy
Only 9 of the 31 studies were rated as high-quality, and 8 of these used a waiting list control group, so the effects of care-as-usual and pill placebo among high-quality studies could not be estimated.
Egger's test was significant (intercept: 1.60 95% CI: 0.38-2.83 p=0.006). Duval and Tweedie's trim and fill procedure resulted in an adjusted effect size of g=0.59 (95% CI: 0.44-0.75 I 2 =62 number of imputed studies: 11). For high-quality studies, no indication for publication bias was found (but this may again be related to the small number of those studies).
Effects of CBT on PAD
The 42 comparisons between CBT and control conditions in PAD 118-147 resulted in a pooled effect size of g=0.81 (95% CI: 0.59-1.04 I 2 =77 NNT=3.53). In the vast majority of the comparisons (N=33), a waiting list control condition was used. The difference between studies using a waiting list (g=0.96) and either care-as-usual (g=0.27) or pill placebo (g=0.28) was significant (p<0.001). The four comparisons of CBT versus care-as-usual even indicated a non-significant effect size (g=0.27 95% CI: −0.12 to 0.65 p=0.17) (Table 1 and Figure 4).
Effects of cognitive behavior therapy (CBT) for panic disorder compared to control conditions: forest plot. CT – cognitive therapy, RELAX – relaxation, BCBT – brief CBT, FCBT – full CBT, BIB – bibliotherapy, GIC – guided imaginal coping, gsh – guided self help, grp – group format, EXT – external cues, INT – interoceptive, PM – panic management, in-p – in person, RESP – respiratory training, ind – individual format, EXP – exposure
The four high-quality studies all used a waiting list control group and resulted in an effect size of g=0.61 (95% CI: 0.27-0.96).
Although Egger's test indicated significant asymmetry of the funnel plot (intercept: 3.62 95% CI: 0.90-6.34 p=0.005), Duval and Tweedie's trim and fill procedure did not indicate any missing studies and therefore the adjusted and unadjusted effect sizes were the same. In the four high-quality studies, no indication for publication bias was found.
Effects of CBT on SAD
The 48 comparisons between CBT and a control condition 148-183 resulted in a pooled effect size of g=0.88 (95% CI: 0.74-1.03 I 2 =64 NNT=3.22). Again, the large majority of studies used a waiting list control group (N=40), with only three using care-as-usual and five pill placebo. The studies using a waiting list control group resulted in significantly (p<0.001) larger effect sizes (g=0.98) than those using a pill placebo (g=0.47) or care-as-usual control group (g=0.44) (Table 1 and Figure 5).
Effects of cognitive behavior therapy (CBT) for social anxiety disorder compared to control conditions: forest plot. EXP – exposure, SOC – social skills, CT – cognitive therapy, RELAX – relaxation, cCBT – computerized CBT, MAGT – mindfulness acceptance group therapy, CR – cognitive restructuring, IGCT – intensive group CT, gsh – guided self help, ind – individual format, grp – group format
Only eight studies were rated as high-quality, and five of these used a waiting list control group. This implies that for SAD there are not enough high-quality studies to assess the effects of CBT compared to care-as-usual or pill placebo.
Egger's test pointed at significant asymmetry of the funnel plot (intercept: 2.46 95% CI: 0.96-3.96 p=0.001), but Duval and Tweedie's trim and fill procedure did not indicate missing studies and the adjusted and unadjusted effect sizes were the same.
Multivariate meta-regression analyses
We conducted four separate analyses, for each disorder, with the effect size as the dependent variable and characteristics of the participants (adults in general or more specific populations), the intervention (format and number of sessions) and the study in general (type of control group, quality and geographic area) as predictors. As shown in Table 2, very few predictors were significant in these analyses, possibly because of the relatively small number of studies per disorder and the relatively large number of predictors.
|Quality of trial||−0.05||0.07||0.46||−0.01||0.07||0.94||−0.09||0.11||0.43||−0.01||0.09||0.92|
|Control condition||Waiting list||Ref.||Ref.||Ref.||Ref.|
|Adults vs. specific target groups||0.01||0.17||0.95||−0.43||0.28||0.14||−0.07||0.38||0.85||0.67||0.75||0.38|
|Number of sessions||−0.01||0.02||0.67||−0.01||0.02||0.60||0.06||0.04||0.13||0.04||0.03||0.19|
|Geographic area||North America||Ref.||Ref.||Ref.||Ref.|
Sometimes we need a little extra help and guidance in life. If you think you could benefit from professional, goal-oriented mental health help, consider giving cognitive behavioral therapy a try.
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What Is Cognitive-Behavioral Therapy?
Cognitive-behavioral therapy (CBT) is a type of behavioral therapy that effectively treats various problems. These include:
- Anxiety disorders
- Alcohol and substance use problems
- Marital problems
- Eating disorders
- Serious mental illness
Numerous research findings show that Cognitive-Behavioral Therapy for Anxiety leads to significant improvements in functioning and quality of life. CBT is as effective or more effective in many studies than other types of mental therapy.
Researchers made CBT advancements based on both science and clinical experience. CBT is an approach for ample research evidence that the methods that have been developed produce improvement. In this way, CBT differs from many other types of psychological therapy.
Does CBT Work?
Over the last few decades, as the field of psychology has moved toward evidence-based practice, there has been more attention in the media about the increasing adoption of cognitive behavioral therapy (CBT) over other methods of treatment. Since there has been more importance placed on treatments with research support, there has been a flood of new research available to guide clinicians and patients to the most effective treatments for psychological problems. In study after study CBT stands out as the most effective treatment for numerous mental health issues. Furthermore, CBT treatments are usually of shorter duration, and the results are more enduring than those of other treatment methods. As a result, therapists trained in more traditional therapies, such as Freudian/psychodynamic therapists, have railed against this method of therapy because, they claim, it oversimplifies problems and aims toward a “quick fix” due to the shorter duration of treatment in CBT.
Below is a chart comparing the effectiveness of CBT with that of medication and other forms of talk therapy. Unfortunately the research is not entirely definitive, as psychotherapy research is still in its relative infancy, not having the benefit of the bottomless pockets of big pharma. However, the initial research is striking in its implication of CBT being the treatment of choice for many psychological problems.
* For all disorders, discontinuation of medication led to a significantly higher relapse rate.
As you can see, CBT outperforms most other treatments for most anxiety disorders. Some disorders appear to respond better to medication than CBT, however, what the graph does not show is the high relapse rate associated with discontinuing medication (In one study, 95% of patients relapsed upon discontinuation of medication). In contrast, CBT treatments have the lowest relapse rates of any psychological treatment. Click here to learn more about Cognitive Behavioral Therapy and Evidence-Based Treatment for Anxiety
You can learn more about the research on CBT with other disorders here.
Barlow, D.H., Gorman, J.M., Shear, M.K., & Woods, S.W. (2000). Cognitive-behavioral therapy, imipramine, or their combination for panic disorder: A randomized controlled trial. Journal of the American Medical Association, 283, 19, 2529-2536.
Bradley, R., Greene, J., Russ, E., Dutra, L., & Westen, D. (2005). A multidimensional meta-analysis of psychotherapy for PTSD. American Journal of Psychiatry, 162, 214-227.