Sex Offender Treatment: Research Results Inconclusive About What Works to
Reduce Recidivism (Letter Report, 06/21/96, GAO/GGD-96-137).
Pursuant to a congressional request, GAO reviewed research results on
the effectiveness of sex offender treatment programs in reducing
recidivism.
GAO noted that: (1) all of the research studies reviewed provided
qualitative and quantitative summaries of sex offender treatment
programs; (2) nearly all of the studies identified limitations in
evaluating treatment effectiveness; (3) there was no consensus as to
which treatment reduces recidivism; (4) the cognitive-behavioral
treatment approach works well in treating child molesters and
exhibitionists, but treatment effectiveness depends on the type of
offender and treatment setting; (5) researchers did not engage in
comparison studies to measure recidivism rates because of the studies'
inconsistent measurements; (6) the research reports lacked sufficient
descriptive information on how program participants are selected and
recidivism measured; and (7) definitive conclusions could not be drawn
about deviant sexual behavior because certain methodological weaknesses
have underscored inferences.
--------------------------- Indexing Terms -----------------------------
REPORTNUM: GGD-96-137
TITLE: Sex Offender Treatment: Research Results Inconclusive About
What Works to Reduce Recidivism
DATE: 06/21/96
SUBJECT: Children
Sex crimes
Sexual abuse
Research reports
Recidivism
Offender rehabilitation
Criminals
Crimes or offenses
Comparative analysis
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Cover
================================================================ COVER
Report to the Chairman, Subcommittee on Crime, Committee on the
Judiciary, House of Representatives
June 1996
SEX OFFENDER TREATMENT - RESEARCH
RESULTS INCONCLUSIVE ABOUT WHAT
WORKS TO REDUCE RECIDIVISM
GAO/GGD-96-137
Sex Offender Treatment Research Results
(182021)
Abbreviations
=============================================================== ABBREV
Letter
=============================================================== LETTER
B-272097
June 21, 1996
The Honorable Bill McCollum
Chairman, Subcommittee on Crime
Committee on the Judiciary
House of Representatives
Dear Mr. Chairman:
This report responds to your request that we review and synthesize
the current state of research knowledge on ways to prevent sex crimes
against children. We subsequently agreed with your staff to cover
sex crimes against both children and adults and to issue two reports
to you. This report describes and synthesizes reviews of the
research literature on the effectiveness of treatment programs for
sex offenders. Specifically, we describe the reviews, report their
findings on the effectiveness of treatment in reducing recidivism,
and report their assessments of the supportability of conclusions
drawn from existing research studies.
The second report, which we plan to issue later this year, will
synthesize reviews of the research literature on education programs
designed to prevent sexual abuse. It will also review research
literature on the likelihood of child victims becoming adult
offenders and what may be done to prevent that.
BACKGROUND
------------------------------------------------------------ Letter :1
In 1993, the most recent year for which published Uniform Crime
Reporting data were available, there were 142,520 arrests in the
United States for forcible rape and other sexual offenses.\1 Public
alarm about sex crimes has prompted legislative activity at both the
state and federal levels. Since 1994, 49 states have enacted laws
requiring sex offenders to register their addresses with state or
local law enforcement officials, and 30 states have adopted
provisions for notifying citizens of the presence of a sex offender
in their community. In December 1995, Public Law 104-71, the Sex
Crimes Against Children Prevention Act of 1995, was passed. This act
increased penalties against those who sexually exploit children
either by engaging in certain conduct or via computer use, as well as
those who transport children with the intent to engage in criminal
sexual activity. In May 1996, the Violent Crime Control and Law
Enforcement Act of 1994 was amended to require the release of
relevant information to protect the public from sexually violent
offenders who reside in their communities. The act, Public Law
104-145, also known as "Megan's Law,"\2 requires community
notification of the presence of convicted sex offenders.
A 1994 survey by the Safer Society,\3 a resource and referral center
for sex offender assessment and treatment, indicated that there were
710 sex offender programs in the United States that treated adult
pedophiles, rapists, and other sexual offenders. This number
represented a 139-percent increase in the number of treatment
programs since 1986. Of these, 137 were residential treatment
programs (90 being prison-based), and 573 were outpatient or
community-based programs.
There are three general types of treatment approaches:
-- the organic, biological, or physical approach includes surgical
castration, hormonal/pharmacological treatment, and
psychosurgery;
-- the psychotherapeutic approach includes individual, group, and
familial counseling; and
-- the cognitive-behavioral approach covers a variety of cognitive
and skills training methods and includes behavior control
techniques.\4
Psychotherapeutic treatment was the primary approach to treating sex
offenders before the 1960s. Today, cognitive-behavioral approaches
predominate. According to the Safer Society's 1994 survey, 77
percent of sex offender programs used the cognitive-behavioral
approach, 9 percent used the psychotherapeutic approach, and 14
percent used other treatment models. No program reported using the
organic model alone as the basis for treatment.
Conducting rigorous research on the effectiveness of sex offender
treatment is difficult for methodological and ethical reasons.
Methodological obstacles include difficulty in selecting a sample of
offenders for treatment who are representative of all sex offenders,
obtaining adequate comparison or control groups against which to
compare offenders receiving treatment, determining how to deal with
offenders who withdraw or are terminated from treatment, and
determining what criteria to use for judging the success or failure
of treatment and information sources to use in making this
determination.\5
According to Furby, Blackshaw, and Weinrott (1989), conditions are
not often conducive to doing rigorous sex offender treatment
research. Rather than designing study samples and data collection
procedures to meet the information needs of their studies, evaluators
are often forced by short time frames and inadequate funding into
using samples and data sources that are readily available.
Ethical issues arise when researchers must decide which offenders
should be admitted into the treatment program. If treatment is
withheld from some eligible offenders, they may be precluded from
receiving the benefits of a potentially therapeutic intervention. If
treatment is provided to all offenders, then the treatment's efficacy
cannot be well-tested empirically, and scarce resources may be
expended on an ineffective program. Comparing alternative treatment
conditions is one way to resolve the ethical dilemma.
--------------------
\1 Excludes prostitution.
\2 Megan Kanka was a child who was raped and killed in 1994,
allegedly by a twice-convicted sex offender who lived on her street.
\3 Robert E. Freeman-Longo et al., 1994 Nationwide Survey of
Treatment Programs and Models (Brandon, Vt.: Safer Society, 1994).
\4 See glossary for a further description of treatment approaches.
\5 Janice K. Marques et al., "Effects of Cognitive-Behavioral
Treatment on Sex Offender Recidivism: Preliminary Results of a
Longitudinal Study," Criminal Justice and Behavior, Vol. XXI, No. 1
(1994), 28-54.
RESULTS IN BRIEF
------------------------------------------------------------ Letter :2
We identified 22 reviews that provided qualitative and quantitative
summaries of research on sex offender treatment. The reviews
discussed the studies in terms of treatment effectiveness and
methodological adequacy.
There was no consensus among the reviews about what treatment works
to reduce the recidivism of sex offenders. The cognitive-behavioral
approach was most often reported to be promising, particularly with
child molesters and exhibitionists. However, because of
methodological limitations inherent in the studies, a quantitative
estimate of the impact of cognitive-behavioral treatment on
recidivism was not attempted in these reviews. Psychotherapy was
generally viewed as not being effective except, in certain cases,
when administered in combination with another treatment approach.
Most research reviews identified methodological problems with sex
offender research as a key impediment to determining the
effectiveness of treatment programs. As a result, little is certain
about whether, and to what extent, treatments work with certain types
of offenders, in certain settings, or under certain conditions.
Nearly all of the reviews identified study design weaknesses, two of
which were most recurrent. First, the reviewers found that
comparison groups (against which to compare treated groups) were
often absent. This made it difficult to judge whether recidivism
results were attributable to the treatment, to the method used for
selecting certain types of offenders for treatment, or to other
factors unrelated to treatment that could affect recidivism. Another
major methodological problem identified in the reviews was
inconsistent and inadequate follow-up periods. Meaningful
comparisons between study results are difficult to make when
offenders are tracked for different periods of time and no attempts
are made to statistically adjust for such time differences. Further,
if sex offenses are underreported, as research has demonstrated, a
short period of follow-up cannot provide the basis for an accurate
assessment of recidivism.
The other two limitations identified in the research reviews
pertained to recidivism measures and how research is reported. With
respect to those measures, weaknesses included inconsistent ways of
measuring recidivism and the fallibility of too few data sources as
the basis for making estimates of recidivism. With respect to the
reporting of research, weaknesses included insufficient descriptive
information to permit the integration and/or comparison of findings
across studies.
Research reviews that reported some promising areas of treatment
agreed with those that did not on the need for rigorous research to
clearly establish the efficacy of sex offender treatment.
SCOPE AND METHODOLOGY
------------------------------------------------------------ Letter :3
We collected, reviewed, and analyzed information from 22 research
reviews on sex offender treatment issued between 1977 and 1996.
These reviews were identified through a multistep process that
included contacting known experts in the sex offense research field,
conducting computerized searches of several online databases, and
screening hundreds of studies on sex offender treatment. We sent the
list of reviews to seven experts in the field to confirm the
comprehensiveness of our list of research reviews.\6
We used a data collection instrument to systematically collect
information on treatment settings and types, offender types,
recidivism measures, methodology issues, follow-up periods, and
conclusions reached from these reviews. (See app. I for a more
detailed description of our methodology.)
We sent a draft of this report to three of the experts previously
consulted to ensure that we had presented the information about the
reviews fairly and accurately.\7 Their comments were incorporated
where appropriate. We did not send a draft to any other agency or
organization because we did not obtain information from such
organizations for use in this study. We did our work between October
1995 and March 1996 in accordance with generally accepted government
auditing standards.
--------------------
\6 Appendix III contains the list of experts we used for this effort.
\7 Appendix III lists the experts who reviewed this report.
DESCRIPTION OF THE RESEARCH
REVIEWS
------------------------------------------------------------ Letter :4
The 22 research reviews covered about 550 studies on sex offenders.
Of these studies, 176 were cited in 2 or more reviews, and 26 were
cited in 5 or more reviews. Given the widely varying levels of
detail provided in the research reviews, we could not always
determine whether reference was being made to a study of sex offender
treatment or to other types of studies on sex offenders (e.g.,
recidivism studies on untreated offenders and studies attempting to
identify sex offender characteristics). Therefore, we could not
precisely determine the total number of studies on sex offender
treatment covered in these research reviews. We also did not
determine how many studies covered in the 22 research reviews were
duplicative in terms of researchers publishing multiple articles
based on the same set of data. At least 10 reviews were authored or
coauthored by individuals affiliated with a sex offender treatment
program. The earliest study included in a research review was
published in 1944, the most recent in 1996.
Almost all of the research reviews provided narrative assessments of
original research studies, with approximately one-half also providing
a tabular summary of at least some of the studies covered. Only one
review performed a meta-analysis, which is a statistical aggregation
of the results from multiple studies to derive an overall
quantitative estimate of the effectiveness of treatment.
Most research reviews did not restrict their coverage to a single
type of treatment, treatment setting, or offender type. Two focused
primarily on a specific treatment setting--one on prison-based
treatment programs and the other on hospital-based programs. Nine
focused primarily on cognitive-behavioral approaches, five on organic
treatment, and one on psychotherapeutic treatment methods. Half of
the reviews included studies on offenders who committed intrafamilial
crimes, while others were not always clear whether the offense was
intrafamilial or nonfamilial.
In assessing recidivism results, most research reviews considered
whether findings were based on official (e.g., parole violation,
rearrest, reconviction) or unofficial (e.g., self-report, report from
family members) indicators of outcome. When official data sources
were described in the research reviews, conviction for a new sex
crime was the single most frequently cited recidivism measure. In
many cases, however, the review did not specify whether the original
study used arrest and/or conviction for a sex or nonsex crime as the
recidivism measure. As indicated earlier, sometimes this was because
the original study itself was unclear about how recidivism was
measured.
RESEARCH REVIEWS VARIED IN
THEIR CONCLUSIONS ABOUT
TREATMENT EFFECTIVENESS
------------------------------------------------------------ Letter :5
Some of the research reviews concluded that treated offenders had
lower recidivism rates than untreated offenders. Others felt that
the studies undertaken were so flawed that no firm conclusions could
be drawn. Many reviewers seemed to be somewhere in between. They
tended to conclude that, while some recent treatment approaches
appeared promising, more rigorous research was needed to firmly
establish their effectiveness. These reviewers asserted that the
more rigorous research should employ larger and more representative
samples of treated and untreated offenders, with longer follow-up
periods and with better indicators of recidivism.
Eighteen of the 22 research reviews included some discussion of
cognitive-behavioral programs, and 12 of the 18 concluded that such
programs were at least somewhat effective. These types of programs
typically involved satiation, aversion conditioning, covert
sensitization, and relapse prevention techniques either used alone
or, more often, in combination with one another.\8
Reviewers who concluded that cognitive-behavioral programs were
effective often emphasized different components as being the source
of their efficacy and differed in terms of what types of offenders
they were most effective in treating. One reviewer, for example,
concluded that deviant sexual behavior could be reduced by techniques
involving covert sensitization, aversion therapy, and a combination
of the two.\9 Another set of reviewers concluded that comprehensive
cognitive/behavioral programs, particularly when administered to
exhibitionists and molesters, held the greatest promise for effective
sex offender treatment.\10
The National Research Council reported in 1994 that anger management
may be appropriate for dealing with violent individuals, but that "it
has not been demonstrated that, in fact, such techniques can alter a
long-term pattern of sexually aggressive behavior."\11
Seventeen of the 22 research reviews discussed organic treatments,
and 6 of the 17 concluded that there was some evidence of
effectiveness. However, there was no consensus even among these
reviewers about a particular drug being most effective, nor about the
duration of positive effects from such interventions.
Fifteen of the 22 research reviews discussed psychotherapeutic
approaches to treatment. None concluded that the various forms of
counseling that characterize this approach were sufficient by
themselves to substantially alter the behavior of sex offenders.
However, a number of reviewers indicated that psychotherapy was
useful in diminishing recidivism when used in conjunction with other
treatments.
Only two reviews attempted to quantify the overall benefit of
treatment programs. A 1990 report by the Canadian Solicitor General
stated: "A reasonable conclusion . . . is that treatment can be
effective in reducing recidivism from about 25% to 10-15%." The only
known and available meta-analysis, or statistical aggregation, of
treatment studies to date concluded that "the net effect of the
sexual offender treatment programs examined . . . is 8 fewer
sexual offenders per 100" (Hall, 1995). Both of these reviews
included a range of sex offender types, treatment settings, and
programs. They did not identify any particular subgroup of sex
offenders for whom treatment was more effective.
Most reviewers, even those who were quite positive about the promise
of sex offender treatment programs, felt that more work was needed
before firm conclusions could be reached. They cited the
methodological limitations of studies as the major obstacle to
drawing firm conclusions about treatment effectiveness. Even those
reviewers who appeared to be among the most positive and optimistic
(at least regarding cognitive/ behavioral programs) echoed the
general sentiment that "there are no conclusive data available from
completely methodologically sound research" (Marshall and Anderson,
unpublished).
--------------------
\8 See glossary for a description of these treatment methods.
\9 Grossman, 1985.
\10 W. L. Marshall and H. E. Barbaree, 1990.
\11 Albert J. Reiss and Jeffrey A. Roth, eds., Understanding
Violence (Washington, D.C.: National Academy Sciences, 1994), p.
113. This study was not one of the 22 reviews we synthesized for
this report because it was not a review of multiple research reports
on sex offender treatment.
RESEARCH REVIEWS IDENTIFIED
METHODOLOGICAL LIMITATIONS IN
EVALUATING TREATMENT
EFFECTIVENESS
------------------------------------------------------------ Letter :6
The research reviews found that conclusions about the effectiveness
of treatment programs were impeded by methodological weaknesses in
the implementation and reporting of the studies. The problems
identified may be grouped into three broad categories: (1)
limitations in the methodological design of studies, (2) limitations
in the recidivism measures used, and (3) limitations in how the
studies were reported.
LIMITATIONS IN STUDY DESIGN
---------------------------------------------------------- Letter :6.1
Nearly all of the reviews identified weaknesses in the study design
as a problem with sex offender treatment research. While numerous
design problems were identified, two were most recurrent. Of the 22
reviews, 15 were critical of the absence of comparison or control
groups, and 12 were critical of follow-up periods that were
inadequate in duration. In addition, 5 were critical of the
inconsistent duration of follow-up periods.
To meaningfully interpret recidivism results, it is important for an
effectiveness study to use a comparison group that is similar on key
characteristics to the treatment group. Using a comparison group
helps answer such questions as (1) what would recidivism rates have
been without treatment and (2) what factors, other than the treatment
program alone, may have affected recidivism? For example, such
studies may find that treatment volunteers, those with significant
community ties, and/or older offenders may have lower recidivism
rates, even without treatment, than other types of offenders.
Without a comparable no-treatment group of offenders against which to
benchmark the results of the treatment group, it is difficult to know
how much of an impact, if any, the treatment program had on
recidivism.
The reviews found that, in the absence of comparison groups,
researchers sometimes compared the recidivism rates obtained in their
study against those obtained in other studies. However, explanations
other than treatment and study characteristics could have accounted
for different recidivism rates in these studies. These include
differences in sex offense reporting rates, apprehension levels, and
prosecutorial policies across different jurisdictions and study
periods.
Research has shown that sex crimes are underreported and that the
longer the follow-up period, the more accurate the assessment of
recidivism. One reviewer noted that "Recidivism rates are most
meaningful if they cover at least a five-year period,
postincarceration" (Becker, 1994), while another suggested that
"studies that follow up offenders for periods of as short as 5 years
or less may be producing substantial underestimates of true rates of
recidivism" (Finkelhor, 1986). Although we cannot be precise about
the average length of follow-up because the research reviews did not
report it in a systematic fashion, it appears that many of the
studies covered in the reviews involved follow-up periods of less
than 5 years.
Not only can follow-up periods be too short to accurately measure
recidivism rates, reviewers also found it difficult to compare the
outcomes of different studies because the studies varied in the
amount of time they tracked offenders after treatment and no
statistical analyses were performed to account for the differences.
Studies reported recidivism rates after 3 months, 1 year, 4 years, 15
years, etc. Follow-up periods even varied within a single study.
Offenders were reportedly at risk for periods ranging from 1 month to
20 years in a single study. While a short follow-up period may not
invalidate comparisons between similar treatment and control groups,
the recidivism rate obtained for both groups is likely to be an
underestimate of the true recidivism rate, because offenders are more
likely to be reported and apprehended for their sex crimes in the
long run than in the short run.
Many of the reviews identified other weaknesses in the research
design of sex offender treatment studies. These weaknesses included
selection bias (e.g., program participants were selected because they
volunteered, so study results may not have been generalizable to
nonvolunteers), the use of small study samples, and failure to
consider attrition from treatment in determining how outcome data
were analyzed.
An ongoing study of institutionalized sex offenders in California was
cited by several research reviews and experts in the field as
employing a research design that attempts to control for many of the
methodological problems besetting other studies.\12 (The design and
preliminary findings from this evaluation are described in app. II.)
--------------------
\12 W. L. Marshall and W. D. Pithers, "A Reconsideration of
Treatment Outcome with Sex Offenders," Criminal Justice and Behavior,
Vol. XXI, No. 1 (March 1994), p. 20.
Vernon L. Quinsey et al., "Assessing Treatment Efficacy in Outcome
Studies of Sex Offenders, "Journal of Interpersonal Violence, Vol.
VIII, No. 4 (December, 1993), p. 514.
LIMITATIONS IN RECIDIVISM
MEASURES USED
---------------------------------------------------------- Letter :6.2
The validity of conclusions about treatment effectiveness is greatly
affected by which data sources are used to measure outcome. Given
that research has indicated that sex offenses are underreported, that
a single data source is likely to be incomplete, and that some data
sources are less reliable than others, the fewer and less reliable
the data sources on which recidivism measures are based, the greater
the likelihood that recidivism rates will be underestimated.
Nearly three-fourths of the research reviews pointed out the problem
of studies relying on too few data sources to measure recidivism.
The reviews criticized studies that relied solely on either official
records or offender self-reports to determine whether program
participants had reoffended. They stated that both official records
and self-reports are likely to contain measurement error. For
example, both arrest and conviction records are likely to yield
underestimates of recidivism if sex offenses are underreported.
Self-report recidivism information may be unreliable. Such
limitations in data sources would not affect the scientific validity
of comparing the recidivism rates of treated and untreated offenders
since both groups would be affected equally. However, these
limitations could affect the accuracy of the recidivism estimates.
Consequently, it is advisable to use multiple data sources to
overcome the weakness of each single data source.
The operational definition of recidivism also has a significant
bearing on the results obtained from outcome studies. In some cases,
recidivism was defined as a rearrest or conviction for a sex offense;
in others, it was defined as rearrest or conviction for any offense.
In still other cases, recidivism was defined only as a rearrest, or
only as a reconviction, with the nature of the crime unspecified.
There seemed to be little consensus among reviewers about what an
optimal indicator of recidivism would be. As a result, it was
difficult to determine whether, and by how much, sex offender
treatment reduced recidivism.
LIMITATIONS IN HOW RESEARCH
WAS REPORTED
---------------------------------------------------------- Letter :6.3
Nearly half of the reviews indicated some type of limitation in how
sex offender treatment studies were reported. The most frequently
indicated limitations included inadequate descriptions of the
treatment programs, failure to report the criteria used to select
study participants, and inadequate descriptions of recidivism
measures. In the absence of such information, it is exceedingly
difficult to synthesize the state of knowledge of sex offender
treatment research. For example, without knowing the contents of a
program or how program participants were selected for it, the ability
to replicate the study and determine whether results are
generalizable is diminished. Without knowing precisely how
recidivism was measured in a study renders comparisons between it and
other studies meaningless.
CONCLUSIONS
------------------------------------------------------------ Letter :7
A substantial number of studies have been done on sex offender
treatment effectiveness, many of which were assessed in the research
reviews described and synthesized in this report. The most
optimistic reviews concluded that some treatment programs showed
promise for reducing deviant sexual behavior. However, nearly all
reported that definitive conclusions could not be drawn because
methodological weaknesses in the research made inferences about what
works uncertain. There was consensus that to demonstrate the
effectiveness of sex offender treatment more and better research
would be required.
---------------------------------------------------------- Letter :7.1
Copies of this report will be made available to others upon request.
The major contributors to this report are listed in appendix IV.
Please call me at (202) 512-8777 if you have any questions.
Sincerely yours,
Laurie E. Ekstrand
Associate Director, Administration
of Justice Issues
SCOPE AND METHODOLOGY
=========================================================== Appendix I
We collected, reviewed, and analyzed information from available
published and unpublished reviews of research on sex offender
treatment. Identifying the relevant literature involved a multistep
process. Initially, we identified experts in the sex offense
research field by contacting the Department of Justice's Office of
Juvenile Justice and Delinquency Prevention and Office of Victim
Assistance, the National Institute of Mental Health's Violence and
Traumatic Stress Branch, the American Psychological Association, the
Association of Treatment of Sex Abusers, Canada's Ministry of Health,
directors of research at various sex assault centers, and selected
academicians. These contacts helped identify experts in the field,
who in turn helped identify other experts. We also conducted
computerized searches of several online databases, including ERIC
(the Education Resources Information Center), NCJRS (the National
Criminal Justice Reference Service), PsycINFO, Dissertation
Abstracts, and the National Clearinghouse on Child Abuse.
We screened hundreds of studies on sex offender treatment to
determine their relevance to our work. This process revealed that a
number of reviews of the research literature had been written. Thus,
because of the level of effort involved in identifying and analyzing
the large number of original research studies on sex offender
treatment and our identification of a sufficient number of reviews of
the research literature, we decided to base our synthesis on the
research reviews.
A limitation of basing our work on the reviews is that we did not
assess the original studies, but rather relied on the descriptions
and assessments provided by the authors of the reviews. The reviews
did not always cite the specific information, such as the types of
offenders treated or whether comparison groups were used, on all
studies they covered. Sometimes, this was because full descriptions
of the research were not provided in the original studies themselves.
We sent the list of reviews to seven experts in the field to confirm
the comprehensiveness of our list of research reviews.\13
Also, as a final check, we conducted a second search of computerized
online databases in March 1996 to ensure that no new reviews had been
published since our original search in October 1995.
We identified 26 research reviews on sex offender treatment issued
between 1977 and 1996. We included 22 of these 26 reviews in our
analysis. We were unable to obtain two reviews. These two were
published more that 15 years ago and were unavailable through
inter-library loan services. Two other reviews were similar to a
third review written by the same author. Of the three reviews by
this author, we selected the review with the most recent publication
date for our analysis. Of the 22 reviews, 10 had been published
since 1990, and one had been submitted for publication but was not
yet published.
We developed a data collection instrument to systematically capture
information on treatment settings, treatment types, offender types,
recidivism measures, methodology issues, follow-up periods, and
conclusions reached. Each research review was read and coded by a
social scientist with specialized doctoral training in evaluation
research methodology. A second social scientist then read the
research reviews and verified the accuracy of the coding of every
item on every completed instrument.
We sent a draft copy of our report to three of the seven experts who
reviewed the comprehensiveness of our list of research reviews.
Appendix III lists these experts. They generally agreed that we
presented information on the research reviews fairly and accurately,
and made technical suggestions that we incorporated into the report
as appropriate. We did not send a draft to any other agency or
organization because we did not obtain information from such
organizations for use in this study.
We did our work between October 1995 and March 1996 in accordance
with generally accepted government auditing standards.
--------------------
\13 Appendix III contains the list of experts we used for this
effort.
CALIFORNIA'S SEXUAL OFFENDER
TREATMENT AND EVALUATION PROJECT:
A TREATMENT PROGRAM WITH A
RIGOROUS EVALUATION DESIGN
========================================================== Appendix II
One sex offender treatment study was cited in several reviews as
incorporating many of the methodological features needed for a sound
assessment of treatment effectiveness.\14 The study, "Sexual Offender
Treatment and Evaluation Project," was mandated and funded in 1981 by
the California legislature. The mandate required that a California
state hospital program be established in accordance with the features
of experimental design so that sex offender treatment could be
appropriately evaluated. In 1985, the California Department of
Mental Health developed a treatment program for sex offenders and
established a long-term, scientific study to evaluate the program.
The California study is a longitudinal effort to evaluate treatment
for institutionalized sex offenders. The study includes three
groups: a volunteer treatment group (offenders who volunteered for
and received treatment), a volunteer control group (offenders who
volunteered for treatment but did not receive it), and a nonvolunteer
control group (offenders who refused treatment). Only offenders with
convictions for rape or child molestation were eligible. Volunteers
were paired and matched in terms of age, criminal history, and type
of offense. One member of each pair was randomly assigned to the
treatment group, and the other remained in the control group.
Offenders matched on the above characteristics who did not volunteer
were later selected for the nonvolunteer control group.
A comprehensive cognitive-behavioral treatment approach primarily
employing relapse prevention was used. Other treatment components
included group seminars on sex education, human sexuality, relaxation
training, stress and anger management, social skills, and substance
abuse and behavior therapy to alter deviant sexual arousal.
Pre-treatment and post-treatment measures were analyzed to assess
whether participants achieved treatment goals. Members of the
treatment group received treatment for 2 years.
Offenders completing the treatment program participated in an
outpatient program for 1 year after release. Both official and
unofficial data are used to determine recidivism. Official data
include records from the federal and state Departments of Justice,
the state Department of Corrections, and parole offices. A new
arrest for either a sex crime or a violent nonsex crime constitutes a
reoffense in this study. Unofficial data include confidential
self-reports about the commission of offenses undetected by the
criminal justice system. The study keeps records and follows up on
participants who drop out of the treatment program before completion.
To date, preliminary results of the evaluation study have not
revealed a statistically significant treatment effect. Overall,
offenders completing the treatment program and the volunteer control
group had approximately the same recidivism rate for new sex crimes.
The nonvolunteer group had a somewhat higher recidivism rate, but it
was not statistically different from the other two groups. For
violent nonsex crimes, the treatment group had a lower recidivism
rate than either control group, but the differences were not
statistically significant. The researchers emphasized the
preliminary nature of these results and the fact that final results
were about 5 years away.
Treatment under this sex offender program ended in 1995. However,
follow-up of participants will continue until the year 2000. Upon
completion of the study, it is anticipated that all participants will
have been followed up after release from the institution for a
minimum of 5 years and a maximum of 14 years.
--------------------
\14 Janice K. Marques et. al. (1994). Also see Janice. K.
Marques, "How to Answer the Question, 'Does Sex Offender Treatment
Work?'" (September 1995). Paper presented at the International
Expert Conference on Sex Offenders, Utrecht, the Netherlands.
EXPERTS CONSULTED
========================================================= Appendix III
The following experts reviewed our listing of research reviews to
help ensure that our coverage of the literature was comprehensive.
Those with asterisks next to their name also reviewed and commented
on the draft report. The objective of the review was to ensure that
we were presenting information fairly and accurately.
Dr. Margaret Alexander
Clinical Director/Sex Offender Treatment Program
Oshkosh Correctional Institution
Oskosh, Wisconsin
Dr. Judith Becker*
Department of Psychology
University of Arizona
Tucson, Arizona
Dr. Lucy Berliner
Director of Research, Harbor View Sexual Assault Center
University of Washington
Seattle, Washington
Dr. John M. W. Bradford
Director, Forensic Service
Royal Ottawa Hospital
Ottawa, Canada
Dr. David Finkelhor
Family Research Lab
University of New Hampshire
Durham, New Hampshire
Dr. William Marshall*
Department of Psychology
Queen's University
Kingston, Canada
Dr. Vernon L. Quinsey*
Professor of Psychology and Psychiatry
Queen's University
Kingston, Canada
MAJOR CONTRIBUTORS TO THIS REPORT
========================================================== Appendix IV
GENERAL GOVERNMENT DIVISION,
WASHINGTON, D.C.
Evi L. Rezmovic, Assistant Director, Administration of Justice
Issues
David Alexander, Evaluator-in-Charge
Douglas Sloane, Supervisory Social Science Analyst
Barry Seltser, Supervisory Social Science Analyst
GLOSSARY OF TREATMENT APPROACHES
============================================================ Chapter 0
AVERSION THERAPY
-------------------------------------------------------- Chapter 0:0.1
Treatment in which visual or auditory depictions of deviant behavior
or arousal, or fantasies of deviant sexual stimuli and behavior, are
linked with and/or immediately followed by a highly physically
aversive stimulus. The aversive stimuli, which can be administered
by either a therapist or the offender, usually consists of foul
smells (e.g., ammonia capsules) or mild electric shocks.
COGNITIVE-BEHAVIORAL
TREATMENT
-------------------------------------------------------- Chapter 0:0.2
Treatment based on the assumption that sexual crimes are attributable
to the interaction of a variety of historical, socioeconomic,
cognitive, behavioral, physiological, and social variables. These
treatments seek to change offenders' distorted sexual cognitions and
perceptions, reduce deviant sexual arousal, and increase arousal to
appropriate behaviors or partners. The broad purpose of this type of
treatment is to get offenders to understand and take responsibility
for their actions, to become motivated for treatment, and to learn
skills to help control their deviant behaviors. Cognitive-behavioral
treatment approaches cover a wide variety of treatment methods and
typically combine behavior control techniques with some type of
counseling or therapy. Behavior control techniques used include
aversion therapy, covert sensitization, relapse prevention, and
satiation.
COVERT SENSITIZATION
-------------------------------------------------------- Chapter 0:0.3
A form of aversion therapy that seeks to reduce deviant sexual
arousal by repeatedly pairing sexually aberrant fantasies with highly
aversive images that produce fear, anxiety, and distress. The intent
is to sensitize the offender to inappropriate stimuli. The therapy
is carried out using fantasies instead of through physical means.
HORMONAL/PHARMACOLOGICAL
TREATMENT
-------------------------------------------------------- Chapter 0:0.4
Treatment that has been called a form of "chemical castration."
Although the medications used in these treatments differ somewhat in
their pharmacology and work in different ways, they are intended to
reduce sexual activity by chemically reducing testosterone levels.
The most well-known drugs used with sex offenders are the hormonal
drug medroxyprogesterone MPA and the antiandrogen drug cyproterone
acetate CPA.
ORGANIC, BIOLOGICAL, OR
PHYSICAL TREATMENT
-------------------------------------------------------- Chapter 0:0.5
Treatments that have traditionally been used to reduce offenders' sex
drives. They include hormonal/pharmacological treatment,
psychosurgery, and surgical castration.
PSYCHOSURGERY
-------------------------------------------------------- Chapter 0:0.6
Surgical treatment that is intended to remove the part of the brain
(in the hypothalamus) believed to control sexual behavior.
PSYCHOTHERAPY
-------------------------------------------------------- Chapter 0:0.7
The primary emphasis of psychotherapy is on the client gaining an
understanding of the psychodynamics of sexual offending. Currently,
however, there is wide variation in the types of therapy provided,
which include individual, group, and family-based counseling.
RELAPSE PREVENTION
-------------------------------------------------------- Chapter 0:0.8
Treatment in which offenders are told that their offense is the
result of a chain of events involving various cognitions and
emotional states that trigger a sequence of behaviors ending in the
commission of a sex offense. Treatment seeks to reduce the risk of
reoffending by providing offenders with an understanding of their
problem and with skills so that the offense chain can be avoided or
stopped.
SATIATION
-------------------------------------------------------- Chapter 0:0.9
A procedure whereby an inappropriate response is eliminated by
repeatedly eliciting it until the desire for the stimulus is
abolished. In other words, the response is sought until it no longer
has reinforcing properties and can even become aversive.
SURGICAL CASTRATION
------------------------------------------------------- Chapter 0:0.10
A surgical treatment used widely in Europe that involves the removal
of the male sex glands. The intent of the treatment is to affect
sexual behavior by reducing testosterone levels. Testosterone is the
principal androgen, or male sex hormone, and is produced in the male
sex glands.
RESEARCH REVIEWS USED IN THE
SYNTHESIS
============================================================ Chapter 1
Barbaree, Howard E., and William L. Marshall. "Treatment of the
Adult Male Child Molester." In Child Sexual Abuse: Critical
Perspectives on Prevention, Intervention, and Treatment, eds. C.R.
Bagley and R.J. Thomlison, (Ontario, 1991), pp. 217-256.
Barker, Mary. "What Do We Know About the Effectiveness of
Cognitive-Behavioural Treatment for Sex Offenders?" Journal of Mental
Health, Vol. II (1993), pp. 97-103.
Becker, Judith V. "Offenders: Characteristics and Treatment."
Sexual Abuse of Children, Vol. IV, No. 2 (Summer/Fall 1994), pp.
176-197.
Becker, Judith V., and John A. Hunter, Jr. "Evaluation of Treatment
Outcome for Adult Perpetrators of Child Sexual Abuse." Criminal
Justice and Behavior, Vol. IXX, No. 1 (March 1992), pp. 74-92.
Blair, C. David, and Richard I. Lanyon. "Exhibitionism: Etiology
and Treatment." Psychological Bulletin, Vol. LXXXIX (1981), pp.
439-463.
Bradford, J.M.W. "Antiandrogen and Hormonal Treatment of Sex
Offenders." In Handbook of Sexual Assault: Issues, Theories, and
Treatment of the Offender, eds. William L. Marshall, D.R. Laws,
and Howard E. Barbaree (New York: Plenum Press, 1990), pp.
297-310.
Cooper, Alan J. "Progestogen in the Treatment of Male Sex Offenders:
A Review." Canadian Journal of Psychiatry, Vol. XXXI (1986), pp.
73-79.
Finkelhor, David. "Abusers-Special Topics." In A Sourcebook on Child
Sexual Abuse, ed. David Finkelhor (Beverly Hills: Sage Publication,
1986), pp. 119-142.
Furby, Lita, Mark R. Weinrott, and Lyn Blackshaw. "Sex Offender
Recidivism: A Review." Psychological Bulletin, Vol. CV, No. 1
(1989), pp. 3-30.
Grossman, Linda S. "Research Directions in the Evaluation and
Treatment of Sex Offenders: An Analysis." Behavioral Sciences and
the Law, Vol. III (1985), pp. 421-440.
Hall, Gordon C. Nagayama. "Sexual Offender Recidivism Revisited: A
Meta-Analysis of Recent Treatment Studies." Journal of Consulting and
Clinical Psychology, Vol. LXIII, No. 5 (October 1995), pp.
802-809.
Hall, Gordon C. Nagayama, Denise D. Shondrick, and Richard
Hirshman. "Conceptually-Derived Treatments for Sexual Aggressors."
Professional Psychology: Research and Practice, Vol. XXIV (1993),
pp. 62-69.
Kelly, Robert J. "Behavioral Reorientation of Pedophiliacs: Can It
Be Done?" Clinical Psychology Review, Vol. II (1982), pp. 387-408.
Kilmann, Peter R., et al. "The Treatment of Sexual Paraphilias: A
Review of Outcome Research." Journal of Sex Research, Vol. XVIII
(1982), pp. 193-252.
Lockhart, Lettie L., Benjamin E. Saunders, and Peggy Cleveland.
"Adult Male Sexual Offenders: An Overview of Treatment Techniques."
Journal of Social Work and Human Sexuality, Vol. VII, No. 2 (1988),
pp. 1-32.
Marshall, W.L., and Dana Anderson. "An Evaluation of the Benefits of
Relapse Prevention Programs With Sexual Offenders" (unpublished).
Marshall, W.L., and H. E. Barbaree. "Outcome of Comprehensive
Cognitive-Behavioral Treatment Programs." In Handbook of Sexual
Assault: Issues, Theories, and Treatment of the Offender, eds. W.L.
Marshall, D.R. Laws, and H.E. Barbaree (New York: Plenum Press,
1990), pp. 363-385.
Marshall, W.L., et al. "Treatment Outcome With Sex Offenders."
Clinical Psychology Review, Vol. XI (1991), pp.465-485.
Ortmann, Jorgen. "The Treatment of Sexual Offenders." International
Journal of Law and Psychiatry, Vol. III (1980), pp. 443-451.
Quinsey, Vernon L., and W. L. Marshall. "Procedures for Reducing
Inappropriate Sexual Arousal: An Evaluation Review." In The Sexual
Aggressor: Current Perspectives on Treatment, eds. J. G. Greer
and I. R. Stuart (New York: Van Nostrand Reinhold, 1983), pp.
267-289.
Quinsey, Vernon L. "The Assessment and Treatment of Child Molesters:
A Review." Canadian Psychological Review, Vol. XVIII, No. 3 (1977),
pp. 204-220.
The Management and Treatment of Sex Offenders: Report of the Working
Group Sex Offender Treatment Review, Solicitor General of Canada
(Ottawa: Minister of Supply and Services, 1990).
*** End of document. ***