Experimental Design
1. Study populations
1.a. Inclusion criteria
We will measure the impact of the intervention on individuals aged between 25 and 35 who were raised in an environment characterized by alcohol or drug abuse problems.
Nevertheless, for ethical- and implementation-related reasons, will be excluded from the study population individuals meeting any of the following criteria:
- Individuals who do not consent to participate in the study
- Individuals who are unable to wait one year to receive treatment
- Individuals who are not looking for a full course of therapy but rather a few counselling sessions
- Individuals who are found not to have sufficient psychological strain or functional impairment to be in need of treatment
- Individuals who have alcohol or drug consumption usage that is so problematic that they cannot benefit from therapeutic treatment until they have received help to reduce their substance abuse
- Individuals who take so much medicine that they cannot benefit from therapeutic counselling
- Individuals who are currently psychotic
TUBA estimates the share of clients meeting at least one of these criteria to be around 10%.
For both logistical and statistical reasons, the study will only be implemented in TUBA’s four largest centers (Aalborg, Aarhus, Copenhagen and Odense), which together represent 56% of TUBA’s clients.
Finally, while the current waiting time to benefit from this intervention exceeds a year in these four centers, it is important to note that for ethical reasons, we will only include in the study sample eligible individuals with an anticipated waiting time over a year (more on this below).
1.b. Selection process
All applicants will be screened following registration by TUBA’s therapists who will decide:
- whether or not they are eligible to benefit from the intervention
- whether or not they can be included in our study sample
While all eligible individuals meeting all our inclusion criteria will be included in the study population, the others may be eligible to receive treatment outside the project framework.
2. Trial design
Upon registration, eligible individuals will be randomly allocated to either a treatment or a control group in order to guarantee the comparability of the two groups prior to the intervention roll-out.
For both financial and logistical reasons, the interventions will be rolled out progressively over a period of 9 months. Four batches of eligible participants will be constituted on the basis of “first-come, first-enrolled in the study.” The first batch will be constituted of all eligible individuals currently on the waiting list with an anticipated waiting time over a year. Subsequent batches will be constituted of all eligible individuals who will have registered to benefit from TUBA’s intervention within a 3-month period (and with an anticipated waiting time over a year). It is estimated that the first batch will be constituted of around 150 individuals and that the subsequent ones will be constituted of around 70 individuals each.
As it is not possible for TUBA to deny eligible individuals treatment for an indefinite period of time, the RCT will follow a rotation design, according to which only the treatment start date will vary across individuals at random. While individuals in the treatment groups will immediately benefit from the intervention, those in the control groups will have to wait for a year.
Importantly, the workload arising from the implementation of the intervention will be shared by all therapists in the four study sites. In turn, this will ensure that the study results are representative of TUBA’s work and not merely of a few therapists.