Dear Steffen, 

What Works with Sex Offenders?

Cognitive‐behavioural treatment is the most effective, especially if paired with

pharmacological treatment (e.g. hormonal drugs that reduce sexual drive). 

Large‐scale reviews indicate that cognitive‐ behavioural programmes which follow the risk, need and responsivity principles are the most effective forms of intervention for sexual offenders. NOMS programmes follow these

principles and although there have been too few robust  reconviction studies, the evidence to date indicates that the programmes produce positive changes in areas known to be risk factors for sexual offending, and reduce sexual and/or violent reconviction.  NOMS will continue to research and

evaluate its interventions with sexual offenders.  

www.justice.gov.uk/downloads/information-access-rights/foi-disclosure-log/prison-probation/foi-75519-annex-a.pdf

Dear Steffen, 

What Works with Sex Offenders?

Cognitive‐behavioural treatment is the most effective, especially if paired with

pharmacological treatment (e.g. hormonal drugs that reduce sexual drive). 

Large‐scale reviews indicate that cognitive‐ behavioural programmes which follow the risk, need and responsivity principles are the most effective forms of intervention for sexual offenders. NOMS programmes follow these

principles and although there have been too few robust  reconviction studies, the evidence to date indicates that the programmes produce positive changes in areas known to be risk factors for sexual offending, and reduce sexual and/or violent reconviction.  NOMS will continue to research and

evaluate its interventions with sexual offenders.  

www.justice.gov.uk/downloads/information-access-rights/foi-disclosure-log/prison-probation/foi-75519-annex-a.pdf

The treatment of sexual offenders varies with the severity of their recidivism risk, generally now measured by the Static99 or one of its progeny - Static99R, Static2002. The greater the risk the less efficacious the treatment. Many high risk offenders are never released from incarceration we do not know a lot about the efficacy of their treatment. In the United States it is generally mandatory to report anyone who has engaged in unreported child sexual abuse or is thinking/planning about doing so, thus many persons who have thoughts of engaging in sexual abuse do not seek treatment. There is a project currently underway in German in which persons who have thoughts of engaging in child sexual abuse and have not done so can be treated and do not have to be reported. I haven't kept up with that data so I do not know efficacy outcomes. 

Research shows that approximately 30% of the male population is sexually attracted to minors, but does not act out upon their interests. We know almost nothing about this population.

I don`t know if the term sexual offender includes pedophiles. But I know that you can`t heal pedophilia with psychotherapy. But what you can do is reduce the risk to become an offender. Normally you use behavioral therapy for that. But what`s a great problem is that there are very few places for the treatment of pedophiles. Furthermore pedophiles don`t tend to ask for psychotherapy on their own. Most come for psychotherapy when they have become an offender and are sent by court. And men who have become an offender have a higher risk to become criminal again than men who are no offenders. The only treatment place for pedophiles in Germany is at Humboldt University in Berlin. Maybe you can ask there for papers. Besides you should find something in PubMed. But there are very few studies on pedophiles by now.

I looked in PMC (Pub Med Central) for sexual offenders AND psychotherapy and found these articles: 

Letourneau, Henggeler, Borduin, Schewe, Mc Cart, Chapman, Saldana 2009: Multisystemic therapy for juvenile sexual offenders: 1-year results from a randomized effectiveness trial. Journal of Family Psychology. 2009 ; 23(1): 89–102.

Letourneau & Borduin 2008: The effective treatment of juveniles who sexually offend. Ethics Behaviour 2008; 18(2/3): 286–306. 

Langström, Enebrink, Laurén, Lindblom, Werkö, Hanson 2013: Preventing sexual abusers of children from reoffending: systematic review of medical and psychological interventions. British Medical Journal 2013; 347: f4630. 

There are even more. You find all articles in fulltext on PMC, the Open Access Forum of the US National Library of Medicine.

Many variables, such as age and the type of treatment, play a large role in SOTx efficacy. The treatment needs to be specialized and standardized with sexual offenders,  the therapists need to be trained and qualified sex offender treatment providers, and the earlier (age of offender) treatment starts the better. There is research that suggests treatment with youth who have presented with problematic sexual behaviors can be quite successful (85-90% reduction rates) when done correctly and to completion, but also other research that suggests adult male offenders to be far less likely for such positive results. 

Relapse rates vary with offense details but are lower than that for all other offenders except murderers.  CBT is used and treatment lowers re-offense even further.  Sexual re-offense is also lower than overall re-offense so the statistic you use depends on how you define the key terms. CSOM (Center for sex offender Management) has some good summary publications on the topic. 

As far as I know, the Americans used to try shocks, brainwashing, and things like that on homosexuals at a certain stage of human history. You will find material even online about these experiments. Woody Allen seems to have engaged in psychoanalysis for decades and ended up becoming a pedophile, right? An assumed one. I had a guy that i saw once in the condition of psychoanalyst and all he wanted to talk about was my sexual experiences. The second time I rang his bell, he appeared with the zipper down, so that I stopped seeing him immediately. I find it hard to believe that psychotherapy has anything to help us in general after considering these two instances, which would be my case and Woody's. I sincerely believe that either you lock sexual offenders with themselves or you bug them somehow to monitor their activities and stop them in the act or people are going to keep on being destroyed because of them. There are not many types of violence that are worse than sexual violence, I reckon. Sex should mean love and we talk about the extreme opposite end of the story here. Sexual offenders should probably try to find intellect in themselves, but part would have to be subconscious. I lost my perfect life, career, and even organism over a relationship with an Australian native man who was an undeclared bisexual. Australia locked me with him, basically, after he proposed to me, like they sent him home as soon as he finished work, etc., and he missed being with other people instead of trying to build the couple's dream, basically. There is something inside of them. This guy had a father who was a pedophile and he had watched him raping his sister, for instance. I myself concluded, during my years of martyrdom, that this guy missed the love of a father, the paternal love, and he then would spend his life searching for it in the other men's dicks, since men would not give him the fatherly love gratuitously if they are adults, is it not? He obeyed a guy called Cameron blindly, whatever he wanted, and I think I am sure they were a homosexual couple, so that that all fits with no miss in my guess. With this, there is realistically nothing you can do, I reckon. You could try to provide this man with a, let's say, late father, another man who would accept giving him what a father  usually gives his kid, but I think I am sure it would not work, just like locking me there with him didn't. There is no healing for such a damage, made during upbringing. That is why I defend The Empire and responsible or rational procreation (The Empire, Blogger, Pinheiro): Things should definitely be fixed by the time there is just a sign of a branch there, you know? After the branch is grown up, there is only a few ways to stop criminal or deviant behavior and drugs or psychotherapy, sincerely, are not inside of those possibilities. 

This is the most recent meta-analysis of the literature on sex offender treatment outcome that I'm aware of. There have been multiple meta-analyses in the past decade -- without a corresponding influx of strong outcome studies! -- but I think this one is particularly helpful because it gets into some of the nuances, e.g., type of treatment, offender risk level. 

http://link.springer.com/article/10.1007/s11292-015-9241-z

Another:

Article Therapeutic Responses of Psychopathic Sexual Offenders: Trea...

Some more: 

Article The Effectiveness of Sexual Offender Treatment for Juveniles...

Article Working with a Sexual Offender with Bipolar Disorder

Chapter Models of Sexual Offender Treatment

Chapter Forensic Psychotherapy for Sexual Offenders: Likely Factors ...

Focusing just on meta-analyses, there have been many conducted in recent years (despite a continued lack of the most methodologically rigorous designs!)

The most recent I'm aware of was published by Schmucker and Losel (2015), and update of their 2005 meta-analysis that focuses only on psychosocial interventions (the 2005 meta-analysis included biomedical treatments)

Schmucker, M., & Lösel, F. (2015). The effects of sexual offender treatment on recidivism: an international meta-analysis of sound quality evaluations. Journal of Experimental Criminology, 11(4), 597-630.

There have also been some meta-analyses the summarize the literature for young offenders who have committed sexual offences (not sure if this was mentioned): http://sax.sagepub.com/content/18/4/401.abstract. I believe the most compelling evidence is for CBT programs that follow the RNR model. There has also been some literature on the Good Lives Model applied to treatment with this population as well.  

As discussed above, there is a need for high quality research studies that examine the efficacy of treatment and moderators of treatment effectiveness. Our outcome studies often look exclusively at the impact of treatment on recidivism over a long period of time. This is of course very important and ultimately the goal of this type of treatment is to reduce recidivism and help people lead meaningful offense free lives.  

I have some other thoughts on measuring treatment effectiveness with this population.  For example, if people who have completed treatment do re-offend, is there evidence for escalation or de-escalation. I would hope that treatment would be associated with de-escalation. Recidivism is often treated as a binary outcome. Additionally, we know that from the general treatment literature that sustained change is much more difficult and certain things are easier to change than others (e.g., attitudes versus behaviour), but I think we have trouble applying this knowledge to treatment with this population. I would argue that meaningful markers of treatment success should also include change on things that are targeted in treatment (e.g., offense supportive attitudes), even if there is a small effect for treatment in terms of recidivism. For example, in treatment studies of depression we don't just evaluate success as never having another episode of depression, but also classify success as reduction in symptom severity and positive changes on functional outcomes. These are just a couple of my thoughts when I think about treatment with this population and I would be curious what other people think.