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Drug Alcohol Depend. 2011 December 1; 119(1-2): 56–63.
PMCID: PMC3629561

Clinician and service user perceptions of implementing contingency management: A focus group study

Abstract

Background

Contingency management (CM), despite the evidence base for its effectiveness, remains controversial, with sub-optimal implementation. In 2007, UK guidelines recommended the use of CM in publicly funded services, but uptake has also been minimal. Previous surveys of service providers suggest differences in opinions about CM, but to date there has been no published involvement of service users in this debate.

Method

Focus group methodology was used to explore systematically the attitudes, concerns and opinions of staff and service users about the use of CM, in publicly funded substance misuse services, to identify the key areas that may be influential in terms of implementation and outcome. Data were analysed thematically using the constant comparative method.

Results

70 staff and service users participated in 9 focus groups. 15 themes of discussion around CM were identified, grouped into four categories: how CM was aligned to the philosophy of substance misuse services; the practicalities of implementation; wider ethical concerns; and how participants perceived the evidence for effectiveness.

Conclusions

Robust process evaluation in different treatment systems is needed to define the active components of CM for implementation. Involvement of service users in this process is essential and is likely to provide valuable insights into the mechanism of action of CM and its effectiveness and uptake within complex treatment systems.

Keywords: Qualitative research, Contingency management, Applied and professional ethics, Behaviour modification, Substance misuse

1. Introduction

Contingency management (CM) is the term for a range of behavioural interventions in which tangible positive rewards are provided to individuals contingent upon objective evidence of behavioural change. There is a well established evidence base (primarily from US treatment centres) for the effectiveness of CM as part of a treatment package for people with substance use disorders (Dutra et al., 2008; Plebani Lussier et al., 2006; Prendergast et al., 2006).

However, specific differences between UK and US health and welfare systems mean that there is likely to be significant differences in the cost-effectiveness of CM interventions depending on whether a service user, provider or societal perspective is taken. Within the UK, health and social care is financed through general taxation to provide universal coverage, which is free at the point of delivery to the patient. This means that the benefits of CM are most likely to be found at a societal perspective, as indeed has been the case with other substance misuse programme (Gossop et al., 2001). In the US, where most of the CM research has been undertaken (Dutra et al., 2008; Pilling et al., 2007) differences in incremental cost effectiveness ratios (ICERs) even between individual sites in multicentre research programmes suggest that treatment delivery factors and variability in patient groups may make a real difference to the cost-effectiveness of CM at an individual and provider level (Olmstead et al., 2007).

Surveys of treatment providers in the US (Benishek et al., 2010; Kirby et al., 2006; McGovern et al., 2004) and a qualitative study from Australia (Cameron and Ritter, 2007) show that a number of factors influence practitioner attitudes to CM, and their likelihood of adopting it as a treatment. These include practitioner understanding of the evidence base, the practicalities of implementing it, as well as the socio-demographic characteristics of the practitioners themselves, and how these might differ within teams, and between practitioners and management (Kirby et al., 2006). The effectiveness of a single behavioural intervention for any chronic medical condition including addictions is likely to be affected by multiple contextual factors including national health policies, funding priorities, individual and institutional views on the role of the state, and the responsibility of the individual in modifying behaviour. To date there have been no published studies from the UK of practitioners’ or service users’ understanding of and attitudes towards CM within the UK substance misuse services, which may further illuminate the processes involved in the uptake of complex and contentious interventions of this kind across different health systems.

In the UK, the national treatment guidelines on psychosocial interventions for drug misuse (National Institute for Health and Clinical Excellence, 2007) recommended the introduction of CM into UK drug treatment services, based on the international evidence, although recognising the paucity of evidence within the UK. Training of clinicians and improving public understanding of the benefits of using CM in substance misuse services were seen as important and necessary steps to be overcome for effective implementation to occur (Pilling et al., 2007). Other than a number of ‘demonstration sites’ that have not published their findings, there has been no systematic implementation of CM in the UK.

The aim of this study was to explore systematically the attitudes, concerns and opinions of staff and service users about the use of CM, as detailed by National Guidelines (Department of Health, 2007; National Institute for Health and Clinical Excellence, 2007), in publicly funded substance misuse services (see Table 1). As there is no previous published data in this area, qualitative methods (focus groups) (Kitzinger, 1995) were used to define key areas, and allow for the identification of factors and processes that may be influential in terms of implementation and outcome.

Table 1
Summary of the principles of Contingency Management from UK guidelines 2007.

2. Method

2.1. Participants and procedures

Focus groups were conducted to explore participant attitudes and opinions about the implementation of CM. Purposive sampling was used to include key stakeholders using and working in and with publicly-funded specialist substance misuse services. Staff and service users from specialist substance misuse services were recruited to one of nine focus groups.

Specialist addiction psychiatrists were identified through attendance at one of two Specialist Clinical Addiction Network (SCAN) conferences. An information sheet was sent out to delegates before each conference to invite them to take part in a focus group. For the recruitment of other staff, we approached four specialist substance misuse teams, two within East London (an area of high urban deprivation) and two within Hampshire, a mixed rural and urban area. Recruitment of staff was through the team manager. Service users were approached by staff and/or team managers working in specialist substance misuse services to participate in one of two focus groups, whilst a third group were recruited through their links with a voluntary service user advocacy group.

2.2. Data collection

Focus groups were conducted between May 2008 and 2009. Each group lasted approximately 1 h and consisted of between two and 12 people. All groups were conducted by a facilitator and co-facilitator, audio digitally recorded and transcribed verbatim. All followed the same procedure. After participants introduced themselves, the facilitator read a pre-written summary of the principles of CM as proposed by the NICE Guideline ‘Drug misuse: psychosocial interventions’ (National Institute for Health and Clinical Excellence, 2007). Participants were asked to discuss their initial thoughts on the guideline with each other for approximately 15 min, before being given three brief clinical vignettes to explore. Each vignette described a scenario for which recommendations were made in the NICE Guidelines (substitute prescribing for opiate dependence, cocaine misuse, completion of immunization programme for Hepatitis B). The vignettes are presented in Fig. 1. After each vignette was presented, the group were asked to discuss whether a client should be offered incentives in the given situation, and the reasoning behind their opinions.

Fig. 1
Case vignettes used to stimulate focus group discussion.

2.3. Data analysis

Data collection and analysis occurred simultaneously using analytic techniques of the constant comparative method (Glaser, 1992; Glaser and Strauss, 1967). All transcripts were read and corrected by the facilitator and co-facilitator of each group, and annotated with field notes taken by the co-facilitator during the group, to ensure that the context of what was said, and other social cues, (e.g., laughter, murmured agreement, etc.) was retained. Transcripts and the associated annotations were imported into the qualitative software package NVivo7 (QSR International Pty Ltd., 2006) to aid analysis. Three of the researchers (JS, AB, SP) read the transcripts and independently defined a preliminary coding scheme which was discussed in the research team. The final coding scheme was generated by an iterative process as further data were collected until saturation was reached. Data were coded by AB independently reading the transcripts and coding all material using NVivo7 (QSR International Pty Ltd., 2006) software, with continuous comparison and discussion where discrepancies arose. The research team discussed and analysed the link between the early dense codes and broader themes to ensure conceptual clarity and consistency across the themes and further recoding where required.

3. Results

3.1. Participants

A total of nine focus groups were carried out, consisting of: current service users (2 groups: N = 2, N = 6), ex service users (1 group: N = 6), specialist addiction psychiatrists (2 groups: N = 9, N = 11) and multidisciplinary staff teams working in publicly-funded specialist substance misuse services (4 groups: N = 9, N = 7, N = 10, N = 10). Overall, there were 70 participants, including: 14 current or ex-service users (patients), 20 addiction psychiatrists, and 36 staff working in multi disciplinary specialist substance misuse teams. The sample captured a range of experience of staff with the mean length of service being 10 years (varying from 10 months to 41 years). Service users had been using substance misuse services for an average of 14 years (ranging from three to 36 years). Participants were aged between 22 and 62 (mean age 45 years old) and 66% of the sample was male.

3.2. Main themes emerging from focus groups

Although the different groups varied substantially in their composition, which resulted in different levels of discourse, and focus around the subject, there was a high level of saturation across the groups in terms of the themes which emerged. In most areas there were substantially similar views expressed by the professional and service users; areas of disagreement or different emphasis are highlighted where these occurred. The final agreed coding scheme contained a total of 40 codes which were applied consistently across all the group transcripts. On review of the content of these codes, they could then be consolidated into 15 main themes, presented here under four broad categories (see Fig. 2), with illustrative examples given in Table 2.

Fig. 2
Focus group categories, emerging themes.
Table 2
Quotations from focus groups illustrating themes from Fig. 2.

3.3. Philosophy of substance misuses treatment and services (see Table 2.1 for examples)

All 9 of the groups spent some time discussing the role of CM and where it ‘fitted’ within current treatment principles. Concern was expressed from the professional groups that it reintroduced a more ‘paternalistic’ approach to treatment that had been moved away from in recent years in the UK. Discussion on the potential impact it might have on damaging any intrinsic motivation of the service user to engage with treatment was a particular feature from those who were now themselves ‘in recovery.’ There was also much debate about how the focus of many services is currently on ‘harm minimisation’ (e.g., needle exchange, immunisation, maintenance substitute prescribing, etc.) rather than on abstinence and recovery. Consequently, the aim of CM to produce drug free urine (see vignette 1, Fig. 2) did not sit comfortably with this.

Seven groups acknowledged the powerful function of simple behavioural measures in shaping and changing behaviour in everyone's life, as well as the importance of ‘rewarding’ people, especially those with so little that was positive and reinforcing in their lives. However, the counter view was also proposed, that relatively small monetary values might reinforce peoples’ sense of lack of worth, whereas rewarding them with a non-monetary incentive tailored specifically to them (e.g., access to training, etc.) might be more beneficial. It is of interest that the two groups of service users currently within the treatment system did not discuss this aspect of CM.

There were differences across the groups as to whether CM as defined in the guidelines represented a form of coercion or whether it was a treatment incentive. Practitioners were divided as to whether take home methadone treatment was one of a range of evidence based therapeutic options available to the clinician (see below), or something more politically driven. If the latter, it fitted their broader concerns about the nature of society (e.g., seeing CM as part of a politically driven policy and the role of the state in peoples lives) which are part of their identity as a citizen, rather than as a health practitioner, and are therefore firmly held and not easily amenable to change (see Section 3.5 below).

As with the other aspects concerning the theories and mechanisms around CM, its use as one of the several therapeutic options was not really discussed by those still in treatment, but was a common and recurring theme across all other groups, particularly the ex-service user group. There was a general consensus that (if there was evidence of effectiveness), the use of CM in principle might be a useful addition to the therapeutic armamentarium. This idea was most positively endorsed by those in the professional groups with greatest experience and training. However, there was a range of views expressed: from unequivocal benefit, through to a more cautious acceptance of it. Concerns were raised that in a system with limited resources it may be seen as a cost saving alternative, replacing established and more valued interventions (e.g., time with a member of staff) and therefore best kept as a ‘last resort’.

Much of the discussions of aspects of treatment delivery are common to other aspects of health care where incentives are used as part of treatment. They were framed within the concepts of health economics and medical ethics and included the following five themes: practicalities of implementation; the opportunity costs of the intervention; the possibility of CM acting as a perverse incentive; issues of equity; and the potential impact on the therapeutic relationship (see Fig. 2 and Table 2.1).

The practicalities and potential problems of implementation was a major theme across all but one focus group (service users) and included aspects that would be anticipated from any discussion about change management. However, concerns were also expressed that were more specific to implementing a behavioural intervention, where it is well recognised that the precise details are integral to the effectiveness of the implementation, and the possibility of unintended consequences. Regarding the implementation of CM within a publicly funded system, participants in four groups (3 professional groups and the ex-service user group) expressed concerns about the opportunity cost of such a change of focus. All nine groups expressed concerns about the feasibility of the level of urine testing (three times per week). However, whilst the professional teams viewed this as being resource heavy and had concerns about the potential opportunity costs of delivery (see Table 2.1), the service user groups felt strongly that such a regime acted as a disincentive that would outweigh any benefit from the financial incentive offered.

Concerns about the notion of equity of access to interventions within the treatment system, and that CM might act to incentivise non-engagement (i.e., act as a perverse incentive) were discussed in 6/9 groups. Concerns about equity were primarily expressed in the professional groups. Service user groups felt it more appropriate for CM to be offered on an individual basis depending on the needs of the service user at a particular time, rather than being mandated to particular groups and certain points in their treatment journey. They specifically felt that it may be more helpful as an initial incentive to encourage people to attend services for assessment rather than once they were already engaged with services as suggested in the guidelines.

Finally, within this category was a discussion around the potential for CM to have a negative impact on the therapeutic relationship, as time could be spent reviewing (and arguing about) urine samples rather than discussing the treatment needs of the service user. Some of the multi-disciplinary team members expressed the view that acting as a ‘broker’ within a CM system where the result of a test had pre conditioned consequences ‘cheapened’ the work that they did. There was no mention in any group that implementation of CM per se might enhance the therapeutic relationship.

3.4. Wider ‘ethical concerns’ (see Table 2.3 for examples)

This category encompasses the broader, often less focussed and more abstract discussion that the groups held around the general concepts of using public money, within a health system that offers universal coverage, to incentivise people to change their behaviour. Frequently raised concerns across the groups included: whether the use of CM for people in substance misuse services further stigmatised this patient group within the public mind? Who was the real beneficiary of this kind of intervention – the service users themselves or the public at large? Was this policy being driven by political motivation rather than the evidence base? These discussions articulated concerns of moral principle and personal belief, which were not evidence dependent, were not changeable within the group discussion or remediable by research or policy clarifications.

One specific aspect mentioned by all 9 groups was the use to which any financial incentive might be put. All recognised the possibility that it might be misused to buy further drugs, and the ex service user group specifically mentioned how giving people ‘extra’ money at a vulnerable point in their treatment pathway may do more harm than good. Whilst issues of autonomy were mentioned, small financial incentives were seen as being specifically targeted at the poorer in society. Whilst any incentive could have a monetary value if traded, a common theme across the groups was that non-monetary incentives targeted to the person's particular need (e.g., funding for electricity, public transport) may be more beneficial.

The public versus personal benefit of CM was felt to be particularly relevant in the scenario where service users were incentivised to complete the full vaccination course for Hepatitis B (see Fig. 1, vignette 3). This was viewed more as a single ‘harm minimisation’ exercise that offered long term protection to others, and therefore with a clear objective and fixed outcome, rather than an as part of a more complex treatment intervention in its own right. Overall, even where participants had expressed concerns over using CM as a means of achieving abstinence in the earlier vignettes, they felt much more comfortable with this more circumscribed intervention that offered a tangible and sustained positive outcome to both the drug user and the wider society.

3.5. Evidence of effectiveness (9 groups)

There were three main sub-themes that were brought up by participants around CM pertaining to the relative importance of effectiveness of CM as an intervention. These were as follows (see Table 2.4 for examples):

  • 1.
    A pragmatic approach that linked in with the discussions around having CM as part of a ‘tool kit’ of interventions. This could be summarised as ‘if it works, use it.’ This stance was primarily taken by the more experienced clinicians.
  • 2.
    A critique of whether the evidence base (which was understood by participants to be primarily from USA treatment centres) may not necessarily work by the same mechanism or to the same effect within the UK health and social care system and that caution was required in assuming direct transposition.
  • 3.
    A firmly held belief that even if there was evidence of effectiveness for an intervention, it did not mean that it was necessarily an acceptable addition to the treatment system. This was a theme from across the groups, generally held by a small number of people within each group, but expressed firmly and consistently, and not appearing amenable to change by the group process.

4. Discussion

The aims of this study were to explore systematically the attitudes, concerns and opinions of staff and service users about the use of CM in publicly funded substance misuse services and to identify the key areas that may be influential in terms of implementation and outcome. Below we summarise the findings and examine specifically what this study adds to the literature in terms of:

  • 1.
    How CM may fit within the context of substance misuse programmes.
  • 2.
    The concerns about implementation.
  • 3.
    Broader concerns that might be seen to represent individuals’ beliefs and concerns as a citizen rather than that as patient or healthcare provider.

The causes of addictions are well recognised to be a complex interaction of biological, social and psychological factors and from a health perspective can be considered within a chronic disease model (McLellan et al., 2000), requiring a collaborative approach between professional and patient if long-term, sustained positive outcomes are to be achieved. Many substance misuse services in developed countries work within a multi-disciplinary, community treatment model. Consequently, the way that new interventions are viewed by clinicians (in their role as individual citizen as well as practitioner), and the collective philosophy of a treatment service will have a substantial impact on the effectiveness and cost-effectiveness of their implementation and uptake (Benishek et al., 2010; Cameron and Ritter, 2007; Kirby et al., 2006; McGovern et al., 2004).

4.1. What are the key aspects underpinning the discussion about the role of CM in substance misuse treatment programmes?

This study highlighted the issues most consistently discussed about the use of CM by service users (both current and past) and health professionals. The 15 different themes are concerns that will need to be considered in any evaluation of effectiveness of CM implementation within different clinical settings, and across different health care systems.

4.1.1. Role of CM within the philosophy of substance misuse programmes

Whilst the evidence base from randomised controlled trials (RCTs) for the role of CM in substance misuse programmes is compelling (Dutra et al., 2008; National Institute for Health and Clinical Excellence, 2007; Pilling et al., 2007) the uptake into clinical practice has been less good (Kirby et al., 2006; Petry, 2006). The results of this study suggest that the overall aims of a treatment programme (e.g., whether the aim is for harm minimisation or abstinence) may be a significant factor in how a single intervention is viewed and the likelihood of its implementation. The methodology of an RCT, even of a complex intervention, specifically attempts to insulate the intervention under examination, from such contextual factors. This study suggests that it is a key concern for professionals that any single intervention is coherent with the broader goals of the service. In addition to this, these results add empirical data to suggestions from other authors (Petry, 2006; Pilling et al., 2007) that the wider societal and political values that practitioners and service users hold as citizens will have an impact on how new interventions are delivered and received within the healthcare system. Government policy and media coverage will also affect and be affected by societal trends at any particular time and have an impact on the perception and implementation of specific health policies (Reinhardt, 1990).

4.1.2. Practicalities and impact on service provision

Whilst some of the discussion of the impact that implementing CM might have within the treatment system could be viewed as an anticipated response to implementing changes in any service and therefore amenable to good change management processes, there are specific details about CM that may impact on its implementation and effectiveness. Our results support the findings of Kirby et al. (2006), that staff have concerns about service costs associated with the schedule of urine tests required, and the need to target more positive treatment outcomes (e.g., improved health and wellbeing) than simply aiming for drug free urines. Our results also suggest that staff and service users felt that the schedule of urine testing was unreasonable and impractical, but could be ‘altered’ to make them more acceptable, whilst the evidence base (Griffith et al., 2000) shows that the frequency of tests is a core component of effectiveness. This demonstrates one potential mechanism for how effect sizes in clinical trials may have a different impact once they are adopted into routine practice.

Who should be offered CM was another consistent concern. The general consensus across the professionals was that it should be available to all service users at a particular point in the treatment system, to fulfil the principles of horizontal equity (providing equal healthcare to those with equal need) (Culyer, 1995) and to stop a system of perverse incentives being set up (i.e., service users being rewarded for non-adherence to treatment). There was also a concern that CM might potentially damage the therapeutic relationship. These are common concerns described in the literature about the use of financial incentives to change health behaviour across a range of conditions (Burton et al., 2010; Marteau et al., 2009; Oliver, 2009; Priebe et al., 2010), but one for which there is currently limited empirical data. However, the service user groups in our sample did not express any such concerns; in fact, all three groups discussed the importance of tailoring a specific incentive (financial or otherwise) only to those who might benefit from it, suggesting an understanding and acceptance of vertical equity (i.e., treating differently those who have different needs) (Culyer, 1995), as a key factor in ensuring CM was most effective. This service user perspective has not, as far as we are aware, previously been discussed in the literature and may have important implications in terms of how CM systems are implemented in practice.

4.1.3. Broader concerns

There was much discussion within the professionals group about CM being considered as a politically driven initiative, which was extended to more general feelings of antipathy towards treatment guidelines. There is a substantial literature on the length of time that it takes to get new research adopted into practice (Benishek et al., 2010; McGovern et al., 2004). Although not all the groups were aware of the literature of the effectiveness of CM, there was a general assumption that a literature existed as the basis of a national guideline. However, as with other studies, practitioners were quick to cite that the research evidence did not reflect the complexity of the service users or clinical situation of routine practice and this affects the perception of its usefulness for clinical decision making (Miller, 1987; Greenhalgh et al., 2004; Kirby et al., 2006; Pilling et al., 2007).

4.2. Strengths and limitations

The study is limited by the relatively small number of participants who took part in the focus groups. Issues of generalisability have a different focus within qualitative work, in that a study of this kind seeks to raise awareness of the concepts and define the phenomena to be further refined and tested for prevalence using other methods (Craig et al., 2008). The smallest focus group only included two female service users (both working as prostitutes) but the relative privacy of this group allowed for an in-depth exploration of the issues that they may have been less happy to engage with in a larger group.

One of the strengths of this study is that the use of qualitative methods allows for a more in-depth and contextualised exploration of the factors which may influence the implementation and effectiveness of a complex intervention such as CM.

Previous studies have shown that there are differences in the attitudes of staff members to CM (Benishek et al., 2010; Kirby et al., 2006; McGovern et al., 2004; Petry, 2006) and this study highlights the complex interaction of professional attributes and personal beliefs that may underlie these attitudes. That many of the concerns about CM appear to be similar in this smaller number of UK practitioners to the larger US surveys (Benishek et al., 2010; McGovern et al., 2004) suggests the validity and generalisability of these results, and some common cross cultural themes that require more robust process evaluation in future RCTs. A final strength of this study is the inclusion of service users within the analysis, and the different emphasis that they bring to treatment decision making.

4.3. The role of process evaluation to help elucidate the core components of CM

There is a growing literature demonstrating the importance of including process evaluation as an essential part of clinical trials of complex interventions (Audrey et al., 2006; Craig et al., 2008; Hawe et al., 2004; Lewin et al., 2009). One suggestion is to standardise the process of the intervention rather than the components themselves (Hawe et al., 2004), thus intervention ‘integrity’ would be defined as the evidence of fit with the principles of the hypothesised change process (in this case CM) rather than trying to reproduce the ‘exact’ conditions in each site. In order to do this, the active ingredients of a complex intervention need to be defined, including delivery mechanisms (Craig et al., 2008). In psychological interventions the attitudes of both staff and patients towards the intervention and their perception of its place within the treatment system, are likely to be important active ingredients and need further elucidation.

4.4. Implications

CM has been shown to be an effective intervention in the treatment of substance misuse. However, it is controversial and uptake within treatment systems has not been as widespread as the evidence would warrant.

There is a need for robust process evaluation of CM in different treatment systems, to define the active components of the process and the mechanism by which they are working (Hawe et al., 2004). Involvement of service users and advocacy groups in this process is essential and is likely to provide valuable insights into the mechanism of action of CM as well as its effectiveness and uptake within complex treatment systems.

Role of funding source

The authors were funded by the Wellcome Trust (grant reference: 081433/Z/06/Z). The funding body had no further role in the study design, in the collection, analysis and interpretation of the data, in the writing of the report or in the decision to submit the article for publication. All researchers were independent from the funding body.

Ethical approval

The study was approved by East London and the City Research Ethics Committee 3 (07/H0705/81). The study was later extended to Hampshire Partnership NHS Trust services and ethical approval was given by Southampton and South West Hampshire Research Ethics Committee (A). Written informed consent was obtained from each participant in person before they took part in a focus group.

Contributors

Authors JS, SP and RA designed the study and wrote the protocol. Authors JS, SP and AB undertook the data collection and analysis, and author JS wrote the first draft of the manuscript. All authors contributed to and have approved the final manuscript.

Conflict of interest

No conflict declared.

Acknowledgements

We thank Ms. Stamatina Marougka who assisted in setting up and co-facilitating the focus groups and transcribing the data. We also thank all participants who took part in the focus groups as well as the Specialist Clinical Addiction Network (SCAN) and the service user advocacy group m.o.r.p.h for their kind assistance in participant recruitment.

All materials used in the conduction of the focus group are available from the authors on request.

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