Intervention research: Appraising study designs, interpreting findings and creating research in clinical practice

Abstract

Speech-language pathologists (SLPs) are increasingly required to read, interpret and create evidence regarding the effectiveness of interventions. This requires a good understanding of the strengths and weaknesses of different intervention study designs. This paper aims to take readers through a range of designs commonly used in speech-language pathology, working from those with the least to most experimental control, with a particular focus on how the more robust designs avoid some of the limitations of weaker designs. It then discusses the factors other than research design which need to be considered when deciding whether or not to implement an intervention in clinical practice. The final section offers some tips and advice on carrying out research in clinical practice, with the hope that more SLPs will become actively involved in creating intervention research. Appraising, interpreting and creating intervention research3

Service delivery and intervention intensity for phonology‐based speech sound disorders

“…This involves clinicians documenting evidence about treatment—including service delivery, intensity, outcomes and modifications—from within their own clinical practice. Such evidence would capture the complexities of clinical caseloads within local contexts and be ‘highly clinically relevant’ (Ebbels : 218). This evidence would also inform SLTs about the effectiveness of their clinical practice for children with SSD, and could demonstrate that their intervention is having a positive outcome for the children on their caseload or lead to appropriate modifications.…”

“…). Such clinically relevant research, developed through partnerships between clinicians and researchers (Ebbels ), could support SLTs as they strive to deliver evidence‐based services to the children on their caseloads.…”

“…Investigations considering the local context would address concerns raised by SLTs that research evidence lacks clinical utility (Foster et al 2015). Such clinically relevant research, developed through partnerships between clinicians and researchers (Ebbels 2017), could support SLTs as they strive to deliver evidence-based services to the children on their caseloads.…”

“…The differences and the range of service delivery models, intervention approaches and intensities found in these two studies of the external and internal evidence bases raise challenges for clinicians and researchers aiming to determine the effectiveness of interventions within a real-world context (Brumbaugh and Smit 2013). This reinforces the need for the widespread creation and dissemination of practice-based evidence (Ebbels 2017, Lof 2011, in which intervention effectiveness can be determined within the realities of clinical practice. Future research needs to consider these realities while simultaneously aspiring to match the empirical recommendations regarding intervention intensity.…”

The effectiveness of semantic intervention for word-finding difficulties in college-aged students (16–19 years) with persistent Language Disorder

“…Thus, we could compare progress during the baseline term (where they received intervention targeting other areas of language), with progress during the term when they received word-finding intervention. This can help to control for effects such as maturation, practice and placebo effects and also regression to the mean (Ebbels, 2017).…”