Listed by Topics
of Sampling Design
The Drug Abuse Treatment Outcome Studies (DATOS) project was a collaborative
national research program for evaluating the effectiveness of community-based
drug treatment in the United States. The National Development and Research
Institute (NDRI) served as the Coordinating
Center as well as one of the four DATOS Research Centers. The other three
centers are located at the Institute of Behavioral Research at Texas Christian
University (TCU), the Drug Abuse
Research Center at the University of California at Los Angeles (UCLA),
and the Services Research Branch of the National Institute on Drug Abuse
(NIDA). As Coordinating Center,
NDRI was responsible for maintaining databases and documentation of DATOS
studies as well as for overseeing data collection for future follow-ups.
Each Research Center organized its studies around a central theme; NDRI
focused on treatment selection, access, and utilization, TCU examined
treatment engagement and retention, UCLA addressed addiction and treatment
careers, and NIDA specialized in applications and policy development.
Results from a series of core studies published
in the Psychology
of Addictive Behaviors (Simpson
& Curry, eds., 1997), Archives
of General Psychiatry (Simpson
et al, 1999), and Drug
and Alcohol Dependence (Simpson & Brown, eds., 1999) describe
some of the highlights and major findings from this project.
Summary of Sampling
A total of 96 treatment programs in
11 large U.S. cities were chosen to reflect typical community-based treatment
services available to the public (see Overview
of Sampling Plan). Geographic location and type of program as well
as the type of clients they served were considered in designing the sampling
plan. Participating programs were located in Chicago, Houston, Miami,
Minneapolis, Newark, New Orleans, New York, Phoenix, Pittsburgh, Portland,
and San Jose. The overall methodology used to compile the database used
in DATOS studies, including client samples and program characteristics,
used to meet research objectives is described by Flynn,
Craddock, Hubbard, Anderson, and Etheridge (1997).
- Intake Sample: A total of 10,010
clients entered the 96 treatment programs that participated in DATOS
during 1991-1993. Overall, this treatment sample was 66% male; 47% African
American; and 13% Hispanic, with a mean age of 33 years. However, these
and other client characteristics varied across modalities, reflecting
their different therapeutic and operational characteristics.
- Follow-up Sample: 4,229 of the
eligible clients who completed the two-stage intake interviews were
selected for follow-up (using a stratified random design). Altogether,
74% (n=3,147) were located, including 70% (n=2,966) who were successfully
interviewed, 1.5% (n=64) who were deceased, and 2.7% (n=117) who refused
to participate. Gender, ethnicity, and average age were not significantly
different between the intake and follow-up samples.
Repeated measures methodology was used, combining
detailed levels of measurement and multiple comparison groups. Data collection
forms included sets of standardized instruments recommended by clinical
experts, and many of the measures used were adapted from earlier large-scale
- Intake 1 and Intake 2 were conducted
by trained interviewers (approximately 1 week apart) and addressed
the following information domains.
- Demographic characteristics
- Employment status, work history, and
- Criminal justice status
- Living situation, and child custody
- Mental health, and psychiatric diagnosis
- Medical and health-related data
- Level of drug and alcohol use before
- Primary drug use and patterns of dependence
- HIV risk behaviors
- During-Treatment Interviews
were completed at 1 month after admission, and again at 3 and 6 months.
Questions were included about service delivery and client satisfaction.
- Follow-up Interviews were administered
at 12-months after treatment termination (although for long-term methadone
clients treated for more than 12 months in DATOS, the follow-up interview
had to be scheduled at 24 months after admission). It replicated much
of the Intake and focused on key behaviors during the year before the
follow-up interview. (An additional follow-up is planned for approximately
48 months posttreatment.)
- Treatment Process Questionnaires
were sent to counselors and program directors at 75 selected programs
approximately 8 months after during-treatment data were collected. Questions
were asked about program and treatment structure, philosophy, available
services, policy, staffing, treatment planning, and aftercare. Program
directors were asked about program organization and financing. Overall,
71 questionnaires (95%) were completed.
- Specially trained and supervised interviewers
were hired to carry out Intake and During-Treatment data collection
in order to assure that programs were not inconvenienced by the research.
Trained professional survey interviewers conducted follow-up surveys
in the community. Quality control procedures were in place for each
step of data management, data editing and entry, and document control.
- Clients were compensated $10 for each
Intake and During-Treatment interview, and $15 for a Follow-up interview.
- Outpatient Methadone Treatment
(OMT) programs administered the medication methadone to reduce
cravings for heroin, in addition to providing counseling and case management
services. Some provided long-term methadone maintenance for clients
and others used methadone to taper to abstinence, but all programs had
expected stays of 2 years or longer. Private for-profit methadone clinics,
nonprofit community-based programs, hospital-based outpatient clinics,
and county-managed programs were represented. There were 29 OMT programs
with 1,540 clients in the DATOS sample.
- Long-Term Residential (LTR)
programs offered drug-free treatment in a residential setting, with
planned stays ranging from 4 months to 2 years. LTR programs in DATOS
included traditional therapeutic communities, modified therapeutic communities,
and other programs requiring in-residence treatment; most expected clients
to stay at least 9 months. There were 21 LTR programs with 2,774 clients
in the DATOS sample.
- Outpatient Drug-Free (ODF)
programs are characterized by a wide range of therapeutic approaches
such as cognitive-behavioral, insight-oriented, supportive, and 12-step.
All planned for clients to stay in treatment for at least 3 months,
and most expected 6 months or longer. Therapeutic community managed
outpatient programs, nonprofit community programs, mental health and
short-term managed programs, and private for-profit programs were included.
There were 32 ODF programs with 2,574 clients in the DATOS sample.
- Short-Term Inpatient (STI)
programs generally kept clients in-residence for up to 30 days, with
a focus on medical stabilization, abstinence, and lifestyle changes.
They included free-standing nonprofit and for-profit short-term programs,
public and nonprofit hospital programs, and county-managed programs.
Due to changes in insurance coverage and a national trend toward "managed
care" during the time this project was being conducted, however,
planned duration of treatment became shorter over time. Most of the
STI programs studied have now closed or been converted to other types
of facilities. There were STI 14 programs with 3,122 clients in the
Simpson, D. D., & Curry,
S. J. (Eds.) (1997). Special Issue: Drug Abuse Treatment Outcome
Study (DATOS). Psychology of Addictive Behaviors, 11(4).
D. D., Joe, G. W., Fletcher, B. W., Hubbard, R. L., & Anglin, M.
D. (1999). A national evaluation of treatment outcomes for
cocaine dependence. Archives of General Psychiatry, 56,
Simpson, D. D. &
Brown, B. (Eds.,) (1999). Special issue: Treatment process and
outcome studies from DATOS. Drug and Alcohol Dependence,
Flynn, P. M.,
Craddock, S. G., Hubbard, R. L., Anderson, J., & Etheridge, R. M.
(1997). Methodological overview and research design for the Drug Abuse
Treatment Outcome Study (DATOS). Psychology of Addictive Behaviors,
11(4), 230-243. [Abstract]
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