A meta-review of Internet computer-based psychological treatments for anxiety disorders

Abstract

Introduction

Internet computer-based psychological treatments have enjoyed rapid growth. Today, there are a number of them available for many mental disorders and psychological problems. Internet-based psychological treatments for anxiety disorders and phobias are amongst the most frequently observed. Treatment results with these resources are promising, but inconclusive.

Methods

This paper reviews 11 systematic reviews and meta-analyses about the efficacy of Internet-based psychological treatments for anxiety disorders, including studies and clinical trials covering the majority of anxiety disorders and phobias, usually with adult patient samples.

Results

In general, these reviews agree on the efficacy of Internet-based psychological treatment as compared with non-treatment groups (with large effect sizes), finding similar efficacy compared with face-to-face therapies. Internet-based psychological treatments are further improved when combined with some type of therapist contact. On the negative side, some systematic reviews highlight high attrition rates of Internet-based psychological treatments.

Discussion

These findings remain inconclusive and more refined reviews (involving patient samples, therapy comparisons, type of therapist contact, etc.) are needed, in order to establish the scope and limits of Internet-based psychological treatments for anxiety disorders.

Keywords

Internet computer-based psychological treatments anxiety disorders review

Introduction

One of the most frequent applications of telepsychology is the delivery of psychological treatment (usually via the Internet). Internet computer-based treatments (ICT) represent a quicker and more flexible alternative to other, manual-based psychological treatments.¹ These packages include, like most manual-based treatments, an explanation of the target problem (anxiety, phobias, depression, eating disorders, etc.), the detection of symptoms related to the disorder/problem, and components of a therapeutic programme. The advantages of ICTs are clear:^2–4 they facilitate access to mental health services when these services are not otherwise available, and for patients with physical mobility problems or geographical difficulties; therapy programmes are accessible around the clock, any day of the week; they can be a good option for patients feeling the stigma of suffering from a mental disorder; and they can be a good option for treating mental disorders with symptoms that usually restrict the mobility of patients outside of their home (such as agoraphobia).

Beyond these shared general components, however, ICTs vary in a number of different ways. As systematic reviews and meta-analyses have pointed out,^5–7 there is substantial heterogeneity in the theoretical orientation, components, access, and presentation of ICTs. This variety represents an initial challenge when trying to determine the efficacy of these treatments, because reviewers, besides having to deal with the usual problems related to differences in the types of psychological disorder addressed, the therapy modality and components used, the therapy procedure followed, the methods for dispensing the therapy, or the number of sessions offered, now also have to consider additional factors related to the nature of ICTs, such as the quality of the Internet presentation (use of video, audio, cartoons, avatars, text, etc.), usually related to the concept of acceptability. Acceptability refers to the degree to which patients (or other users) are satisfied or at ease with a service and are willing to use that service. It implies aspects such as feeling comfortable, easy access, easy learning, and attractive presentation.⁸

Despite these challenges, there are currently many ICTs available for the treatment of a number of mental disorders or psychological problems (most of which address emotional problems). For example, Newman et al.⁹ found 123 studies just for anxiety and depression. The growth in the number of these treatments has led to an appreciable number of systematic reviews or meta-analyses having already been conducted, including a meta-review (i.e. a review of the reviews) of ICTs for depression.¹⁰ The conclusions of these reviews do not always coincide, but they do share some common features:^3,11 (i) ICTs are effective compared with the non-treatment control group, and frequently have an efficacy level which is similar to that of face-to-face treatment; (ii) the efficacy of ICTs is improved with well-structured and comprehensive programmes (i.e. those that include several therapeutic techniques and offer a sufficient number of sessions) based on cognitive and behavioural approaches; (iii) ICTs have been found to be more effective at treating mild to moderate problems; (iv) contact with a therapist (or “guided ICT”) seems to be key: there is greater effectiveness when the patient can have some contact with a therapist (whether programmed or not); and (v) ICT is a cost-effective procedure.

However, depending on the systematic review or meta-analysis reviewed, and given the heterogeneity of the studies selected, even these few shared conclusions are subject to discussion, with even the higher efficacy of ICTs with therapist guidance having been called into question.^6,12 Despite the new challenges presented by ICTs, their differential efficacy needs to be established. One possible alternative would be to analyse only those ICTs with better clinical trial designs, and with a higher number of studies available; this is what Foroushani et al.¹⁰ did for ICTs for the treatment of depression.

In this sense, the aim of this study is to review the efficacy of ICTs for treating the most frequent mental health problems: anxiety disorders and phobias.¹³ In order to integrate efficiently the existing information and provide data for rational decision-making, we will perform a meta-review, establishing whether scientific findings are consistent and can be generalized across populations, settings, and treatment variations. In particular, we will focus on well-controlled and high-quality clinical trials to show the power and precision of estimates of treatment effects, to limit bias, and to improve the reliability and accuracy of conclusions.

Method

This study was performed as proposed by the PRISMA statement regarding the information to be included in a systematic review. The PRISMA statement is a tool designed to help improve the clarity and transparency in the publication of systematic reviews.¹⁴

Identification and selection of studies

A systematic literature search was performed to identify reviews of the effectiveness of telepsychology for the treatment of anxiety disorders in the following databases: Medline, Psycinfo, Academic Search Complete, PubMed, PsycARTICLES, Redalyc, Scopus and Cochrane. No exploration period was specified, as it is a recent area of clinical psychology that has arisen following the development of the Internet. The review was conducted up to February 2015.

The search strategy for each electronic database was developed using a combination of the following medical subject headings:

(1) Review, systematic review, meta-analysis.

(2) Telehealth, telemedicine, telepsychology, telepsychiatry, telecare, Internet computer-based treatments, computer assisted therapy, computer mediated cognitive-behavioural treatment.

(3) Anxiety, phobia, anxiety disorder, anxiety problems, generalized anxiety disorder, panic disorder, panic attack, obsessive–compulsive disorder, posttraumatic stress disorder, acute stress disorder, agoraphobia, specific phobia, and social phobia.

Inclusion and exclusion criteria

The scientific papers included in this review were reviews, systematic reviews, and meta-analyses examining the efficacy of telehealth programmes in the treatment of anxiety. The articles included were restricted to those published in the English or Spanish language in peer-reviewed journals. Furthermore, each paper included at least one term from each of the three medical subject headings. Also, reviews had to include total or partial data addressing anxiety.

Items excluded were those that were not reviews, systematic reviews, or meta-analyses, and those that did not directly address the effectiveness of the intervention using quantitative data. Efficacy was evaluated in psychological terms, not just in economic terms. Also excluded were articles published in languages other than English or Spanish.

Selection process

Two reviewers carried out the study selection process individually. Reviewers used the following blind and structured hierarchical strategy: first, reading titles and abstracts; second, reading the selected articles in full; third, selecting articles fulfilling the specific inclusion criteria. In case of discrepancies, a third reviewer verified the selection criteria.

Methodological quality of the studies

An assessment of methodological quality was included using the PRISMA declaration for systematic reviews, with a detailed explanation and justification for each of the 27 proposed items. These dichotomous items were structured into seven sections: title, abstract, introduction, method, results, discussion and conclusions, and limitations. A mean score was calculated for each section and review. Two reviewers performed the assessment of 25% of the selected papers. The Kappa coefficient reached (0.78) showing a considerable degree of agreement between raters. We then proceeded to the assessment of the full studies.

Data extraction

The same researchers who selected the studies also extracted the data independently. Any disagreements were resolved by consensus. The following information was extracted from each of the selected articles: age of population, treatment and control conditions, duration in weeks, number of studies, effects in post-test and follow-up, and main results.

Results

Identified studies

Using the search strategy described above, a total of 749 references were identified. After eliminating 693 non-systematic reviews or meta-analytic studies, and 14 duplicates, 42 references were selected by title and abstract. Figure 1 shows the search and selection process used to identify references.

Figure 1.

Flow chart showing search and selection process used to identify references.

Included and excluded studies

Out of 42 systematic reviews selected and read in full, 13 were included (see Table 1). Three references were excluded because of the unavailability of specific data and 26 were excluded because they were not systematic reviews or did not meet some of the other inclusion criteria describe in the protocol.

Table 1.

Summary of studies included in the review.

First author	Age of population	Treatment & control conditions	Duration (weeks)	Number of studies	Quality review	Post-test g/d (ES) 95% CI	Follow-up g/d (ES) 95% CI	Main results
Spek¹⁵	Adults	Waitlist & information	4–8	12	1	.96 (69,1.22) Panic disorder 1.0 Social Phobia 0.8 PTSD 0.8		Online interventions for anxiety had a large mean effect size. Conclusions. In general, effect sizes of Internet-based interventions for symptoms of anxiety were larger than effect sizes for depressive symptoms; however, this might be explained by differences in the amount of therapist support.
Cuijpers¹⁶	Adults	Non-computer therapy & FTF	2–10	23	1	1.08 (0.84,1.32) Panic/agoraphobia: 1.01 (0.76,1.36) Social Phobia: 0.90 (0.57,1.22) Other phobias 1.11 (0.37,1.84) Other 0.81 (0.56,1.05) Computer-based psychotherapy vs. FTF: −0.06 (−0.22,0.10)	ICT vs. control: 0.55 (0.02,1.08) ICT vs. FTF 1–3 months −.27 (−0.66,0.12) 6 months .05 (0.18,0.28) ICT at post-test vs. ICT at follow-up 1–3 months .09 (−0.15,0.33) 6 months −.02 (−0.34,0.30) 12 months .03 (−0.27,0.32)	Overall mean effect size of computer-based therapy compared with non-ICT was high. Computer-based therapy was as effective as face-to-face and both did not differ significantly.
Bee¹⁷	All ages	Control & FTF	2–16	13	1	Control 1.15 (0.81–1.49) FTF −0.11(−0.60,0.38)		Overall, the effect size would suggest that remotely delivered psychotherapies for anxiety do have the potential to be clinically effective. A comparison of the efficacy of technology-mediated versus face-to-face psychotherapy with a smaller difference for anxiety-related disorders was obtained.
Reger¹⁸	Adults	Waitlist, placebo & FTF	nr	19	1	ICT vs. waitlist: 0.77 (0.56,0.98) ICT vs. placebo: 0.88 (0.70,1.31) ICT vs. treatment as usual: 0.00 (−0.38,0.38)		Weighted mean effect sizes showed that Internet-based treatments were superior to waitlist and placebo assignment across outcome measures. The effects of Internet-based treatment also were equal to therapist-delivered treatment.
Amstadler¹⁹	Adults	Waitlist & CBT base on FTF	4–10	36	1	Panic disorder Pre-post effect: 1.27 (0.05,2.9) PTSD: Pre-post effect: −1.15 (−0.15,1.43) FTF 2.40 (nr)	Panic disorder Pre-follow-up: 1.74 (0.5,3.7) PTSD: Pre-follow-up: 0.86 (0.32,1.31)	Internet-based interventions have demonstrated superiority to the control condition in amelioration of anxiety symptoms. Also it has been found to be highly effective in treating anxiety disorders than traditional face-to-face services. Both treatments were significantly effective in reducing anxiety symptoms. Moderate to large effect sizes for Internet-based intervention conditions were found across studies.
Waller²⁰	Adults	Non-ICT & waitlist	nr	36	0.89	Panic disorder/ phobias 2.03 (0.81,5.09)		ICT is likely to be an effective and acceptable intervention, but people in the ICT arm were twice as likely to drop out, though this was not seen in all studies.
Andrews⁵	Adults	Waitlist & treatment conditions	nr	22	0.89	Social phobia 0.92 (0.74,1.09) Panic 0.83 (0.45,1.21) GAD 0.92 (0.74,1.09)		ICT showed superiority in outcome over control groups (waitlist). The effect sizes were substantial. The studies comparing ICT with traditional face-to-face CBT showed that both modes of treatment appeared equally beneficial.
Calear²¹	Children & adolescents	Waitlist & FTF intervention	10	8	0.89	0.39 (0.15,0.56)	.25 (nr)	The results provide support for the effectiveness of Internet-based programmes for child and adolescent anxiety. Six of the eight studies reported post-intervention reductions in symptoms of anxiety or improvements in diagnostic ratings. The online intervention had a significant positive effect on anxiety. This study included a face-to-face intervention group that had a significant effect on anxiety symptoms. There was no significant difference between the FTF intervention group and the online intervention group.
Wade²²	All ages	Waitlist	5–8	10	0.96	ICT with therapist support 1.0 (nr) without support 0.5(0.2,0.3)		Evidence has emerged of medium-to-large effect sizes for Internet-based CBT in the treatment of disorders such as social phobia, panic disorder, agoraphobia, and PTSD.
Griffiths²³	All ages	Waitlist, placebo, passive information control	1–13	18	0.93	0.73 (0.29,1.74) Anxiety 0.76 Panic 1.01 Social phobia 0.90 Post-traumatic 0.76		All of the anxiety interventions yielded positive results on at least one measure, except for the non-therapist arm of one social phobia study.
Sloan²⁴	Adults	Waitlist & FTF intervention	2–14	13	1	PTSD Telehealth vs. waitlist: 1.01 (0.76,1.26) Telehealth vs. FTF: −0.68 (−0.98, −0.39) CB telehealth vs. supportive counselling telehealth: 0.11 (−0.38,0.60)		Results indicate that telehealth treatments are associated with significant reduction in PTSD symptoms and result in superior treatment effects relative to a waitlist comparison condition. However, telehealth intervention produced an inferior outcome relative to a face-to-face intervention.
Andersson²⁵	Adults	FTF intervention	nr	13	1	Overall −0.01 (−0.13,0.12) Social Anxiety −0.16 (−0.47,0.16) Panic Disorder 0.05 (−0.20,0.30)		Guided ICT produce equivalent effects to face-to-face treatment on social anxiety and panic disorders.
Davies²⁶	Adults	Inactive control, active control & comparison intervention (FTF, online support group, etc.)	2–12	14	1	ICT vs. Inactive control 0.56 (−0.77,−0.35) ICT vs. active control 0.18 (−0.98,0.62) ICT vs. comparison intervention −0.10 (−0.39,0.18)		ICT produce beneficial mental health outcomes in students for anxiety. However, improvements in anxiety outcomes were not supported when intervention was compared to active control or comparison intervention. ICT and comparison interventions showed equivalency in their effect upon improving anxiety outcomes

ICT: Internet computer-based treatments; nr: not reported; FTF: face-to-face treatment; CBT: cognitive behaviour therapy; PTSD: post-traumatic stress disorder; ES: Effect Size; CI: Confidential Interval

Methodological quality

The methodological quality of the reviews was high (see Table 1), exceeding 0.80 in all of the studies (average for reviews and sections = 0.96). The items with the lowest scores were “additional analysis results” and “limitations”, both included in the discussion section.

Characteristics of included studies

Based on the data extraction sheet, the main characteristics obtained for each systematic review are shown in Table 1, grouped under six different themes: age of population, treatment and control conditions, duration in weeks, number of studies, effects at post-test and follow-up, and main results.

In the studies, adults were the most numerous group (76.9%) and adolescents and children the least (7.7%); 15.4% of studies included both age groups. The duration of the studies ranged from 2 to 16 weeks; the average being about 7 weeks (Mean = 6.71). The number of studies included in each review ranged from 8 to 36 (mean = 19).

All of the studies selected had used computer-based cognitive behavioural therapy. They all compared online treatment against control conditions, which included waitlist, attention placebo or activities without active cognitive behavioural therapy features, and psychoeducation groups, depending on the study in question. The results indicate a greater effectiveness of online interventions as compared with the control. Nine studies compared online interventions against face-to-face treatments as the control intervention. Most of these studies found that the differences between ICT and face-to-face therapies were not statistically significant (77.7%). Some 11.1% of reviews found that ICT could be more successful than face-to-face treatment of anxiety disorder. Only 22.2% reported worse results for ICT in comparison with face-to-face treatment, particularly in panic disorder and phobias.

We calculated mean effect sizes based on the primary outcome measure at post-test in each study. The primary effect size corresponded to standardized mean difference (Hedges' g or Cohen's d). The magnitude of Hedges' g or Cohen's d may be interpreted using Cohen's²⁷ recommendations: small (0.2), medium (0.5), and large (0.8). All of the reviews reported positive results for online treatment compared with the control conditions (d = 0.90) at post-test. However, some reported partial negative results compared with the control or lower scores compared with the face-to-face treatment results (d ranges from 0.06 to 2.03), principally due to the attrition rate in online interventions. The reviews included the most representative anxiety disorders. The most frequent was panic disorder and the least frequent was generalized anxiety disorder (GAD).

The follow-up results showed d ranges from 0.02 to 1.74 compared with ICT at post-test, from 0.25 to 0.55 compared with the control, and from 0.05 to 0.27 compared with face-to-face treatment.

Discussion

A total of 11 references of systematic reviews and meta-analyses were included in this review. The studies reviewed used computer-based cognitive behavioural therapy to treat different anxiety disorders with a high methodological quality. The mean number of studies included in each review was 19 and the treatments had a duration of around 7 weeks. The reviews covered practically the full spectrum of anxiety disorders (including panic, phobias, post-traumatic stress disorder (PTSD), and GAD).

The results of this meta-review provide support for the use of Internet computer-based treatment of anxiety. We found a large overall mean effect size (when effect sizes are reported) of the online interventions in comparison with the control interventions. Although many of the studies reported high attrition rates, the benefits of ICT were superior to those of waitlist groups or placebo treatment. Also, the efficacy of ICT was mainly equal or superior¹⁹ to treatment delivered face-to-face. Thus, ICT is an efficacious treatment, offering increased convenience and reduced clinician time that would otherwise be required for face-to-face treatment. It offers increased access to treatment for those suffering from anxiety.

These findings are consistent with published meta-analyses for anxiety disorders. These studies reported that computer-aided psychotherapy was superior to control conditions, and did not significantly differ from face-to-face interventions.^16,18 This efficacy is higher than that attained with other disorders, such as depression.¹⁵ Thus, therapist-assisted treatments remain optimal in the treatment of clinical levels of depression in comparison with computer-based self-help cognitive and behavioural interventions, which are efficacious in the treatment of subthreshold mood disorders.⁹ Also, Internet-based treatments for anxiety disorders have been found to show a similar efficacy compared with face-to-face treatment, although these results are inconclusive: the review by Sloan et al.²⁴ reported less efficacy for online therapy (for PTSD), while the review by Amstadter et al.¹⁹ reported more efficacy for Internet-based treatment.

In general, reviews including studies that combined online therapy with external therapist support (in the form of face-to-face treatment, e-mails, etc.) showed improved efficacy.^16,17,22 These results demonstrate how providing even very brief face-to-face support from a therapist to users of computer-based psychotherapy could be extremely useful. This is a clear benefit, given the difficulties encountered when providing services and professional support to mental health service users in many countries.²⁸

Waller and Gilbody²⁰ have pointed out that most of the studies reported equal efficacy of online interventions as compared with face-to-face interventions, but interestingly, online studies showed much higher attrition rates. This result may imply that those efficacies need to be analysed in an intend-to-treat context, because many anxiety patients cannot benefit from better treatment options. In this sense, it is necessary to establish the profile of patients who could benefit from online therapy, as well as the profile of those who have high a possibility of dropping out of treatment. Obviously, this can only be done when the treatment options are viable options: if patients do not have the possibility of receiving well-established face-to-face treatment (due to mobility difficulties, geographical problems, no mental health service available, etc.), the Internet becomes the best option, despite the attrition rates.

The timing of outcome assessment is a relevant study design issue to be considered. It is of course important to examine outcomes immediately following the completion of treatment; however, beneficial outcomes should be sustained beyond the immediate post-treatment assessment period. The majority of the studies included in our meta-review only examined the outcome immediately following the completion of treatment. When looking at follow-up results separately, a lower effect size was found. This lower effect shows that the efficacy of ICT is not sustained at the same level for a substantial period of time.

This meta-review has several limitations. The 13 reviews did not use the same inclusion criteria; consequently, the differences observed between them could be due to these variations. Examples of this variability include the different participant characteristics, treatment approaches, and clinical scales used, or the clinical efficacy criteria applied. Also, the conclusions of the present meta-review are limited by the methodological problems observed in the primary studies.

Additional grounds for caution include the fact that studies that included follow-up measures pointed out how ICT-related gains decreased over time. Also, high attrition rates could be understood to mean that there may be patient profiles that are more suited for ICT use, according to their psychological characteristics and motivational states, and not only contextual characteristics, such as geography difficulties or mobility problems. Finally, as long as we do not control for the amount of therapist support or therapist contact involved in mixed interventions, we cannot establish if such an intervention should be defined as an ICT with external support, or as face-to-face treatment with support offered via new technologies.

Despite these limitations, our study indicates that Internet-based interventions, especially those with therapist support, are effective for treating anxiety disorders. Based on the convincing evidence presented above, dissemination in routine practice should be considered. ICT could be a very promising line of treatment, reaching people who otherwise would not receive treatment.

Of course, even with the promising results obtained in this meta-review, clinicians and therapists must be prudent when it comes to adopting a widespread use (or strong recommendation) of ICT for anxiety disorders, because it may not necessarily always be the best treatment option. A careful analysis of patient characteristics, particularly in terms of their commitment, motivation, and adherence to treatment, could help inform the decision to choose an ICT option and also optimize its efficacy.

As there are already a number of systematic reviews and meta-analyses available regarding the efficacy of ICT, future systematic reviews could improve the knowledge in this field by using narrower and more precise inclusion criteria. This could include, for example, selecting studies that compare ICT against well-established face-to-face treatment. Computer-based cognitive behaviour treatments must be comparable with face-to-face treatment in content, duration, and sample size and include pre- and post-test measures and follow-up. Also, assessment should focus on studies with reliable and valid efficacy measures (including clinical efficacy criteria) and external therapist support. Because therapist support is an important variable in determining the efficacy of ICT, future systematic reviews could control the therapeutic contact with patients according to its (i) frequency, (ii) systematization (scheduled contact versus non-programmed contact), and (iii) therapist support delivery mode (e.g. via phone, email, networks, video-conference and/or face-to-face contact). In sum, it can be said that more precise systematic reviews and meta-analyses are needed, reducing the literature search to, at least, well-developed ICT programmes with matched face-to-face interventions, follow-ups, and clinical efficacy measures. It is also essential to control at a detailed level for external therapist support.

Footnotes

Declaration of Conflicting Interests

The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Funding

The author(s) disclosed receipt of the following financial support for the research, authorship, and/or publication of this article: This study was supported by the following grants: PSI2009-09836, PSI2013-42912-R (Spanish Ministry of Economy and Competitivity), and SolSubC200801000084 (Canary Islands Agency for Research, Innovation and the Information Society).

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