Is Self-Guided, Internet-Based Cognitive Behavioral Therapy Actually Effective?

You can find a selection of Cognitive Behavioral Therapy based apps in the app stores these days, but can mobile phone apps really provide effective therapy? Scientists in a 2017 meta-analysis say yes, but with a few caveats. 

Photo by Markus Winkler. A smartphone rests on a wooden table. On the smartphone is a single large "thinking " emoji face.

TL;DR: This article touches on some of the risks and benefits of utilizing self-guided, internet-based CBT. We review the results of a 2017 meta-analysis (study of studies) by Karyotaki et al., which investigated the question of whether or not internet-based CBT (iCBT) is effective. The results show that iCBT can work to reduce the number of depressive symptoms and the severity of those symptoms. This article also touches on caveats and where this study falls short in its ability to interpret the data or any causal links between iCBT and improving mental health.

Cognitive Behavioral Therapy is an evidence-based framework for helping people understand and work through situations that are causing that person psychological distress (Josefowitz & Myran, 2017). It has many precursors and approaches to psychology and was developed into its own theory in the 1960’s by Dr. Aaron Beck ( For a cool overview of CBT from a software engineer's perspective, check out this earlier blog post by Chris Simpson. Using CBT as a method utilizes several techniques designed to help someone who is working on their mental health take a step back and analyze how different aspects of the situation (e.g. their behaviors, emotions, physical state, thoughts, etc.) all influence each other and influence the situation. The diagram below illustrates how the five factors have interactions and relationships to each other:

Diagram of the CBT "Five-factor" model

Just like the recipe for cake relies on interactions between ingredients, technique, and temperature, the product of our response to any situation is a result of how we think, feel, and act about it -- change one or more of the elements, and you can end up with a totally different reaction to the same situation. 

Navigating through these complex domains is usually done with a trained therapist, who will have a good understanding of the foundations of CBT and can use his or her clinical judgement with regards to which tools to use and when. Traditional CBT is designed for use in face-to-face therapy or even teletherapy. The benefits of this include building a strong trust and rapport (relationship) between the client and therapist, and individualized therapy for maximum benefit. Having a therapist work with you in real time ensures that you are doing the exercises correctly and they can help untangle and process all of the complex thoughts and feelings. Recently (in the last 10 years or so), CBT has been brought online and exercises can be done by anyone at any time.

Photo by United Nations. Illustration of a child and an adult facing each other, the adult is reaching her arms to embrace the child through a phone screen.

Internet-based CBT (iCBT) refers to self-guided programs and exercises based in CBT that an individual can do online, such as through an app or website, which may involve automated feedback from the app or website but does not provide support with regards to therapeutic content (Karyotaki et al., 2017). The difference between iCBT and traditional CBT is that iCBT doesn’t use a trained therapist. Instead, iCBT is self-guided and relies on the person doing iCBT to complete exercises and work on problems on their own. Doing iCBT alone can have its drawbacks, namely lack of knowledge and experience, which can lead to less effective or smaller progress, or difficulty following through with the exercises that a therapist would be able to coach through. Not having a therapist also means that the person working through their mental health doesn’t have a trained ally who is a great source of resources or assistance if situations get very serious. In short, iCBT is not a replacement for a therapist. 

However, self-guided iCBT can have its own benefits, too: It is more affordable than traditional therapy due to the cost of the therapists’ rate; iCBT is also more convenient and accessible, not requiring appointments and can be done at any time of the day and only requires access to an app or internet connection. Using iCBT has the added benefit of being discreet, as iCBT activities can be completed whenever someone has a private moment to themselves. Having access to iCBT activities and strategies at your fingertips requires no disclosure to anyone else, and no waitlist.

As mentioned earlier, traditional CBT is evidence-based, meaning that many randomized controlled studies and meta analyses have been conducted and shown roughly the same conclusion: that CBT works and really helps people feel better. Most of the studies have looked at the results of in-person, traditional CBT administered by a trained therapist. Few studies have been able to look at if iCBT shows similar results. Why so few? Mostly because cell phones and personal computers and laptops didn’t exist in the 60’s, when CBT was introduced. Now that some studies on iCBT have been conducted, a team of researchers did a meta-analysis (a study of studies) to see if the results between individual studies are consistent in answering the questions, “With regards to people with depression, does internet-based CBT work?”

The study we are highlighting today is a meta analysis, which looks at multiple studies that have been reported, and analyzes them as a group to see if the results of these studies can make a stronger, more generalizable  statement about the effects of iCBT on depressive symptoms.

Photo by Dennis Cherkashin. A yellow and black smartphone displays emojis.

To do this, the researchers combed through all the randomized controlled trials using iCBT that they could find which compared iCBT to other control conditions, namely a waiting list, usual care, or attention control (side note: attention control refers to a control group that gives the participant the same interpersonal interaction time as a participant in another experimental group, but no therapeutic value is provided. It is analogous to a placebo trial). Once they found published studies that fit their criteria, they reached out to the original studies and asked them to share their data so that they could combine all of the data together, to form a super-database of sorts to do their analysis.

Overall the researchers found 16 studies that met their exact specifications for the conditions they were examining, of which they were able to obtain the individual participant data for 13 of them to use for this study. From these 13 studies, they analyzed the results of 3876 individual participants. The researcher’s first objective was to look at the pretreatment scores of all of the participants together using the depression screening questionnaires mentioned above. They found that the participants had an average score of 25.7 on the Center for Epidemiologic Studies-Depression screen (a score of 16 or more indicates depression), an average score of 28.3 on the Beck Depression Inventory I or II (a score of 21-30 indicates moderate depression), or an average score of 14.1 on the Patient Health Questionnaire-9 (a score of 10 or more indicates depression). This finding indicates that the participants, on average, were in fact experiencing significant depressive symptoms.

The second objective of this study was to determine whether or not the participants experienced a 50% or more decrease in depressive symptoms. This was captured as a yes/no dichotomy. They found that the iCBT group outperformed the control groups, meaning that people who participated in iCBT were more likely to experience a 50% or more reduction in depressive symptoms by the time the post-treatment test was given compared to the other groups, and that the longer a person was able to stick to their treatment, the more benefit they experienced.

The final objective was to look at any changes in symptom severity (as opposed to number of symptoms in objective 2). The researchers found that self guided iCBT was statistically significantly more effective than the other control groups in reducing symptom severity and improving treatment response (again, that means a 50% reduction or more in symptoms). 

These findings are very encouraging as the rise of iCBT could lead to better accessibility in using tools to help more people become active in their mental health care. That said, there are some limitations to this study as it does not explain the whole picture. For one, this study does not explain why iCBT did better than controls, the researchers only conclude that it outperformed controls, and even then it did not give detailed information as to which controls it outperformed and by how much. Second, there was a high amount of heterogeneity in the individual participant data, meaning that it’s hard to make broad generalizations when your participants are quite different from each other. Other factors may influence these findings- remember when we saw that sticking to treatment was a big indicator of success? That may be because of a third factor- maybe certain genders are more likely to stick to treatment longer, or people who are older, or people who live in a particular country, etc. The point is here, we don’t have enough information to know exactly what factors moderate the results. What we do know, however, is that for many of the people whose data were analyzed in the study, depressive symptoms did seem to be reduced for those who did iCBT compared to those who were in the control conditions that did not address their depressive symptoms. 

Because CBT is a framework (and not a specifically regimented program) for how to look at and address a problem, there are many different tools and activities within the CBT toolkit that can be customized to help you with your specific needs. Whether you choose to start exploring via iCBT and/or with a licensed therapist, know that it’s okay to advocate for yourself first and we highly encourage you to customize the wide range of options available to make it work for you.


Levis, B., Benedetti, A., & Thombs, B. D. (2019). Accuracy of Patient Health Questionnaire-9 (PHQ-9) for screening to detect major depression: individual participant data meta-analysis. bmj, 365.

Josefowitz, N., & Myran, D. (2021). CBT Made Simple: A Clinician's Guide to Practicing Cognitive Behavioral Therapy. New Harbinger Publications.

Karyotaki, E., Riper, H., Twisk, J., Hoogendoorn, A., Kleiboer, A., Mira, A., ... & Cuijpers, P. (2017). Efficacy of self-guided internet-based cognitive behavioral therapy in the treatment of depressive symptoms: a meta-analysis of individual participant data. JAMA psychiatry, 74(4), 351-359.

Miller, K. (2020, January 9). CBT Explained: An Overview and Summary of CBT. Retrieved from

Vilagut, G., Forero, C. G., Barbaglia, G., & Alonso, J. (2016). Screening for depression in the general population with the Center for Epidemiologic Studies Depression (CES-D): a systematic review with meta-analysis. PloS one, 11(5), e0155431.