Testing a social mechanism of recovery high schools: Peer affiliation as a mediator of substance use outcomes.

Qualitative research is increasingly conducted with randomized controlled trials (RCTs) to provide insights into stakeholders’ perceptions and experiences, as well as contextual factors influencing the design and implementation of trials and interventions (). In a recently published methodological guidance on patient-focused drug development, the US Food and Drug Administration (FDA) highlighted the important benefits of using qualitative research during the process of intervention development and evaluation, which included, among others, identifying clinical outcomes that are important to patients and explaining low trial recruitment rates (). The increased attention that regulatory authorities are currently paying to these issues indicates that the criteria of efficient health technologies are moving away from solely focusing on evidence of effectiveness to considering the multiple stakeholders involved, their behaviors, and the complexity of the real world in which they live (). There have been extensive discussions about the potential uses of qualitative research with trials. These typically focus on how qualitative methods can contribute to the generation of evidence of effectiveness before, during, or after large-scale trials (). A 2013 mapping review conducted by O’Cathain et al. () identified twenty-two subcategories capturing the various ways that qualitative research can be used in conjunction with RCTs, including issues related to the intervention, the trial, outcomes, measures, and target conditions (). Their results yielded an empirical foundation for previous debates, corroborating the idea that qualitative research has, in practice, been used in very diverse ways. Yet, the extent to which the potential value of qualitative research is currently realized remains poorly understood, largely due to how the findings of RCTs and associated qualitative research are presented in published literature. It is often unclear what follow-up work has arisen as a result of the qualitative findings, making it difficult to assess whether qualitative research has indeed fulfilled its promise (). Since the use of qualitative methods in the context of RCTs has increased substantially over the last decade, it is worthwhile revisiting whether and how research practices may have shifted. This study maps the changing landscape a decade after O’Cathain et al.’s framework (), which was based on publications from 2008 to 2010 (;). Although an increasing number of qualitative studies have been conducted with clinical trials, their use remains uneven across different types of interventions. According to a systematic review of major trial registries, only around 5 percent of drug trials and 5 percent of device trials incorporated qualitative components (). Similarly, a mapping review focusing only on RCTs estimated that these two categories of qualitative studies accounted for 27 percent altogether (). The limited use of qualitative methods in the context of drug and device trials might be attributed to the perception that these interventions are highly standardized and less influenced by contextual variation. Yet, the complexity of drugs and devices may take different forms. For example, patients’ perceptions and experiences of drugs or devices might influence their adherence to long-term use (–). Similarly, health professionals’ views toward a drug or device can shape patients’ treatment choices (–), create hesitations around trial recruitment (), compromise protocol fidelity (), or even affect post-market surveillance (). This study sought to refine the understanding of when and where qualitative methods can be used in conjunction with RCTs involving drugs or devices, to assess the extent to which existing qualitative studies have fulfilled their intended contributions, and to empirically develop a set of guiding questions to assist the design of future qualitative research.