Models of care

Prior to discussing specific treatment options, mention needs to be made of the various models that have been proposed to treat co-occurring conditions. Four approaches have been suggested (see Table 37):

• Sequential treatment.
• Parallel treatment.
• Integrated treatment.
• Stepped care.

There has been much discussion of models of care for clients with co-occurring conditions, but very little research is available to determine which models may be better suited for which conditions. AOD workers may need to make pragmatic decisions as to which model is most appropriate for individual clients.

It should be noted that there are several ways in which the term ‘integrated’ is used with regard to AOD and mental health. In these Guidelines, we use the term ‘integrated treatment’ to refer to the simultaneous treatment of a person’s AOD use and mental health by a single provider or service, which is distinct from the concept of ‘integrated services’ (combining different services such as mental health and AOD) and ‘integrated systems’ (combining service policies, funding, budgets or administrations) [111]. The idea of integrated treatment for two disorders has considerable intuitive appeal and presents a number of advantages over other treatment approaches. Integrated treatment by a single provider or service helps to ensure that there is a single point of contact (the client does not ‘fall through the gaps’), there are common objectives, treatment is internally consistent, the relationship between AOD use and mental health conditions may be explored, and communication problems between agencies do not interfere with treatment [658].

While applying an integrated approach to the treatment of co-occurring conditions is appealing, there has been very little research undertaken directly comparing this approach to parallel or sequential models [659, 660]. Many studies examining the efficacy of integrated treatments compare them to ‘treatment as usual’ or other forms of treatment for either the AOD use or the mental health condition alone. Although the findings from these studies are promising, these designs cannot establish the efficacy of integrated treatment relative to parallel or sequential treatment [659, 661–669]. Similarly, while there is intuitive appeal to applying a stepped-care approach to co-occurring conditions, few studies have examined stepped-care interventions for co-occurring conditions and these approaches have not been compared to other models. More research is needed to guide treatment approaches in this space.