Prison-based health and wellbeing interventions: evidence review and survey of provision

3. Findings - Effectiveness of interventions

Decision-making tools (classification of intervention effectiveness^[8] and an evidence of effectiveness decision tree)^[9] were used to inform how the evidence was synthesised for this review. These tools were developed for and initially implemented within the Scottish Government report What Works to Prevent Violence Against Women: A Summary of the Evidence. They have been adapted within this report to ensure a consistent and transparent approach to classifying the effectiveness of interventions to promote physical health and wellbeing in the prison population.

The decision tree leads to the following six categories of effectiveness, which have been colour-coded. Annex B provides definitions for each of these evidence classifications and Annex C shows the different paths (i.e., conclusions) which can be made about the evidence included in the review:

• Effective (Green)
• Promising (Amber)
• Mixed (Amber)
• No effect (Red)
• Negative effect/potentially harmful (Red)
• Inconclusive (Grey)^[10]

It should be noted that the inconclusive category is distinct from the no effect category as it indicates either there is insufficient evidence to make a judgement on the impact of an intervention (e.g. only pilot evaluations available) or indicates the need for further research and evidence before conclusions can be drawn on the effectiveness of an intervention.

When using the evidence of effectiveness decision tree the following aspects were considered when classifying the available evidence:

• The relevance of the evidence: must include outcomes related to health or wellbeing
• What the evidence says about the effectiveness of the intervention
• The strength of the available evidence (i.e., was a control group included in the study design?)

When considering the strength of the available evidence the following limitations were identified across the research literature:

• Heterogeneity of interventions
• Heterogeneity of measures used for emotional, physical and social outcomes
• Lack of control/comparison groups
• Small sample size
• Lack of follow-up evaluation
• Selection biases

As a result of the intervention classifications and limitations above, gaps in the literature are included in Section 6 of this report.

The physical health and wellbeing interventions reviewed fell into the effective, promising, mixed or inconclusive categories which are shown in Table 1 below. The examples provided in the table are interventions which have been evaluated in the UK. A brief description has been provided in the table to summarise why each intervention category has been awarded that particular classification.

Table 1: Table showing interventions classified by effectiveness

Effective

Yoga, mindfulness, and meditation interventions (e.g., 10 week Yoga course)

Effective: A number of high-quality evaluations (i.e., strong-moderate evidence which compared an intervention group to a control group) of this intervention category indicated that there were improvements in participants' physical health and wellbeing in the prison population.

Promising

Horticultural interventions (e.g., Greener on the Outside: For Prisons)

Promising: There was qualitative evidence which reported that horticultural interventions had positive effects on the physical health and wellbeing of the prison population. As there were no quantitative evidence, a conclusion as to whether the interventions were the reason for the positive effects on the physical health and wellbeing of the prison population cannot be made.

Art and creative interventions (e.g., Good Vibrations)

Promising: There was qualitative evidence which reported that art and creative interventions had positive effects on the wellbeing of the prison population. As there were no quantitative evidence, a conclusion as to whether the interventions were the reason for the positive effects on the physical health and wellbeing of the prison population cannot be made.

Mixed

Animal-based interventions (e.g., Paws for Progress)

Mixed: Qualitative evidence showed positive effects of animal-based interventions on the physical health and wellbeing of the prison population. Quantitative evidence, however, was mixed with some showing positive effects and others no effect.

Sports-based interventions (e.g.,2^nd Chance Academies)

Mixed: Qualitative evidence showed positive effects of sports-based interventions on the physical health and wellbeing of the prison population. Quantitative evidence, however, was mixed with some showing positive effects and others no effect.

Inconclusive

Peer-support interventions (e.g. Listener scheme)

Inconclusive: Limited eligible evidence for the effectiveness of peer-support interventions was found to be included in this review. Consequently, it is not possible to draw reliable conclusions on the effectiveness of these interventions.