Assessing the fidelity of a behavioural intervention involving academic detailing in general practice: a sub-study of the 'Implementing work-related Mental health guidelines in general PRacticE' (IMPRovE) trial.

Background: Assessing the fidelity of intervention components enables researchers to make informed judgements about the influence of those components on the observed outcome. The 'Implementing work-related Mental health guidelines in general PRacticE' (IMPRovE) trial is a hybrid III trial aiming to increase adherence to the 'Clinical Guidelines for the diagnosis and management of work-related mental health conditions in general practice'. IMPRovE is a multifaceted intervention, with one of the central components being academic detailing (AD). This study describes the fidelity to the protocol for the AD component of the IMPRovE intervention.

Method: All AD sessions for the trial were audio-recorded and a sample of 22% were randomly selected for fidelity assessment. Fidelity was assessed using a tailored proforma based on the Modified Conceptual Framework for fidelity assessment, measuring duration, coverage, frequency and content. A descriptive analysis was used to quantify fidelity to the protocol and a content analysis was used to elucidate qualitative aspects of fidelity.

Results: A total of eight AD sessions were included in the fidelity assessment. The average fidelity score was 89.2%, ranging from 80 to 100% across the eight sessions. The sessions were on average 47 min long and addressed all of the ten chapters in the guideline. Of the guideline chapters, 9 were frequently discussed. The least frequently discussed chapter related to management of comorbid conditions. Most general practitioner (GP) participants used the AD sessions to discuss challenges with managing secondary mental conditions. In line with the protocol, opinion leaders who delivered the AD sessions largely offered evidence-based strategies aligning with the clinical guideline recommendations.

Conclusions/implications: The IMPRovE AD intervention component was delivered to high fidelity. The sessions adhered to the intended duration, coverage, frequency, and content allowing participating GPs to comprehend the implementation of the guideline in their own practice. This study also demonstrates that the Modified Conceptual Fidelity Framework with a mixed methods approach can support the assessment of implementation fidelity of a behavioural intervention in general practice. The findings enhance the trustworthiness of reported outcomes from IMPRovE and show that assessing fidelity is amenable for AD and should be incorporated in other studies using AD.

Trial Registration: Australian New Zealand Clinical Trials Registry ACTRN 12620001163998, November 2020.