Wheeze in preschool children is common and distressing, leading to impaired quality of life, repeated hospital admissions and family stress.1 2 In the UK, its prevalence in 2017 was 7.7%. Although overall prevalence declined between 2008 and 2018, wheeze attack rates increased significantly, with preschoolers experiencing the highest attack rates compared with older children.3 4

Currently, there are no clinical tests to guide treatment decisions in preschool wheeze; management relies on medical history and symptom reporting. Some children have underlying eosinophilic airway inflammation and respond well to inhaled corticosteroids (ICS), whereas others do not.5 Understanding the underlying airway pathology could enable better-targeted therapies and improve outcomes.5 The 2024 European Respiratory Society (ERS) Task Force suggested biomarkers like blood eosinophil count (BEC) and allergic sensitisation could help identify children more likely to respond to ICS.6 However, before biomarker-based strategies can be implemented, their acceptability to parents and feasibility in clinical practice must be assessed.

Sekhon et al outlined that acceptability depends on perceived effectiveness, burden, ethics, understanding and practicality.7 Few studies have explored the acceptability and feasibility of finger-prick blood sampling, skin-prick testing (SPT) and fractional exhaled nitric oxide (FeNO) tidal breathing (offline) testing in preschool children with wheeze.

This study uniquely combined parent and HCP perspectives on the acceptability and feasibility of finger-prick, SPT and FeNO tidal breathing (offline) testing in NHS primary care settings, thereby supporting future personalised treatment approaches for preschool wheeze and informing the design of a planned randomised controlled trial of preschool wheeze biomarker-based treatment.

The TAILOR study was a pragmatic, observational study on preschool wheeze (November 2021–December 2023). We examined whether BEC, allergic sensitisation and FeNO alone or in any combination were associated with future wheeze attacks and ICS treatment. Families were approached in NHS primary and secondary care settings and given 7 days to decide on participation after receiving study information. Informed consent was obtained before baseline testing, which included finger-prick BEC test, SPT for allergic sensitisation and FeNO offline testing. A second optional biomarker testing occurred 3–4 months following baseline. Children were followed up for 1 year to record wheeze attack occurrence. At the end of follow-up, a focus group (FG) or one-to-one interviews with one parent per family and HCPs was conducted to collect their views on the acceptability and feasibility of biomarker-guided ICS treatment.

Criterion sampling was used to recruit parents who had taken part in biomarker sampling within the TAILOR study. All parents were invited by AP via telephone to participate in FG or interviews. Convenience sampling was used to recruit HCPs (general practitioners (GPs) and nurses) working in NHS via email. Practices involved in identification and approach of eligible families in the main study were contacted by AP, while the Thames Valley and South Midlands National Institute for Health and Care Research (NIHR) network and the East Midlands Research Delivery Network (RDN) approached all practices in their network. Written informed consent was obtained from all participants.

Topic guides for FG and interviews were developed based on a literature review7–12; they were reviewed by the study team before use, but not formally piloted. Open-ended questions encouraged participants to share views freely. Topic guides’ core structure remained consistent, but discussions were iteratively adapted using earlier FG insights to explore broader relevance with later participants. Interviews and FG were conducted online via MS Teams by AP (male pharmacist, PhD candidate), with a second researcher present for notetaking. Sessions were audio-recorded, transcribed and pseudonymised by AP. Transcripts were not returned to participants for comments/corrections. No remuneration/voucher was provided for their participation.

Thematic analysis was performed within the NVivo V.14 software. Coding was conducted by AP and GL (female postdoctoral researcher, qualitative experience) to explore differences or similarities and ensure preconceptions did not unduly affect analyses. Analysis followed Braun and Clarke’s iterative process,13 actively seeking contrasting views to ensure a balanced interpretation. Themes were derived from the data. Pragmatism was used as the philosophical paradigm, while an inductive approach was used to develop inferences.14 Parent themes were derived from FG discussions, whereas HCP themes were drawn from one-to-one interviews and two FGs; individual interviews were often conducted to maximise participation given conflicting schedules.

To our knowledge, this is the first study to explore both parent and HCP perspectives on the acceptability and feasibility of finger-prick, skin-prick and FeNO tests. The findings showed these tests are acceptable and feasible under the following conditions: (1) there is evidence of their effectiveness, (2) empathetic interaction and clear communication between parents and HCPs is established and (3) there is evidence of their cost-effectiveness to support NHS funding.

Parents seek empathetic interactions, clear explanations and shared decision-making from HCPs, consistent with previous research highlighting the importance of reassurance and clearer communication.8 18–22

Our findings align with those of Wajid et al,18 who found that parents were frustrated by diagnostic uncertainty and favoured investigative tests to guide treatment pathways. However, our study additionally included the views of HCPs, providing a broader, implementation-focused perspective.

Most parents preferred SPT because it gave them an active role in helping their child. This finding aligns with Clement et al, who reported that parents’ interest in allergies is driven by their desire to improve their child’s condition and exclude allergies as the causing factor for their symptoms.10 However, SPT detects allergic sensitisation, not allergy, leading to misconception regarding causality. In contrast to parents, HCPs regarded SPT as less feasible due to the training required, time demands and the risk of adverse reactions, despite the extremely low incidence of anaphylaxis (one in 55 000 patients) reported in large studies.23

HCPs highlighted several practical considerations for implementation. Tight schedules and heavy workloads limit their ability to incorporate these tests into routine practice, making it essential to integrate testing into existing workflows without increasing burden. Successful implementation would require nurses or HCAs’ training on both technical (ie, biomarker tests) and communication skills (incorporating distraction-based techniques (ie, toys and cartoons)) to facilitate children’s cooperation. The success of these tests also depends on HCPs’ skills.24 Although not mentioned by HCPs, offering biomarker tests in community-based healthcare settings, such as community diagnostic centres (CDCs) or intermediate care clinics, could provide flexible appointment structures, relieve pressure on GP appointments and facilitate wider adoption.25

Health economics also affects feasibility. The costs of biomarker devices and consumables are significant barriers unless centrally funded. Negotiations with clinical commissioning groups are therefore essential to make these tests available across GP practices. El-Osta et al reported that the lack of NHS reimbursement for point-of-care (POC) tests deters primary care adoption due to high initial and ongoing costs.26 Comparable challenges were reported for the introduction of HbA1c POC tests in UK primary care, but funding routes were developed.27 28 Similar routes could support adoption of biomarker tests for preschool wheeze. Future cost-effectiveness analyses should consider device/consumables costs, staff training, workflow adjustments and long-term savings from reduced exacerbations and unscheduled healthcare visits. It should be noted that parents’ out-of-pocket expenses (eg, travel and subsistence), as well as willingness or ability to pay for biomarker tests outside NHS (eg, private testing or co-payment) were not assessed as we focused on NHS primary care costs. Future work should explore this, as out-of-pocket costs may affect acceptability.

In this study, HCPs mentioned that biomarker test adoption depends on proven ability to predict outcomes and guide treatment decisions, aligning with Ciardiello et al.29 They prefer quick, time-efficient tests, supported by guidelines and acceptable to patients.29 High costs and lack of evidence or guideline support for the biomarker tests would prohibit clinical practice implementation.29

Parents in this study emphasised transparency and children’s safety to consider participation in a future intervention study. They expressed concern about randomisation in the control group, fearing it may deprive their child of potential benefits, as previously identified.30 Building trust between parents and researchers, explaining randomisation, blinding and right to withdraw are critical to improve participation and prevent misconceptions and complaints during the study.31 32 Best practices, such as the use of multimedia consent tools, lay summaries and parent advisory groups could support informed decision-making and improve recruitment rates. Additionally, parents of children with poorly controlled wheeze are more likely to participate in studies, while those whose children’s condition is stable are less inclined to do so.21 Finally, HCPs highlighted the need for realistic recruitment targets and adequate funding for participating practices. These concerns should be explicitly addressed in trial design, by involving more practices with smaller recruitment targets and providing resources to offset additional workload.

The key strength of this study is that it captured the perspectives of both parents and HCPs regarding the three biomarker tests, helping to identify important barriers to implementing them in NHS primary care. While this study offered valuable insights, several limitations should be acknowledged. Although data saturation (ie, the collection of qualitative data until the addition of new data does not yield new themes33) was deemed achieved within parents’ FG, not inviting families who agreed to one-to-one interviews may be a limitation. These parents might have felt uncomfortable sharing personal experiences in group settings. The inclusion of parents with prior experience with biomarker tests enabled informed, pragmatic reflections on acceptability. However, this limits transferability to test-naïve populations. Participants also lacked ethnic diversity. Factors such as culture, health literacy and the presence or absence of previous biomarker testing could influence perspectives but were not explored. Future qualitative studies should consider deeper enquiry into these aspects of behaviour and belief, as well as broader recruitment strategies and purposive sampling strategies to support inclusion of children from diverse ethnic and demographic backgrounds to strengthen findings’ transferability. Purposive sampling was not used to enable all parents from this study to participate, while convenience sampling for HCPs was used due to the study’s time constraints, potentially leading to a less diverse sample. Additionally, HCPs lacked firsthand experience with the biomarker tests, making their feedback theoretical rather than practical. Although the sample was relatively homogeneous in professional roles, it was diverse in terms of gender, clinical experience and practice size, allowing collection of varied perspectives on biomarker testing implementation in primary care. Despite these limitations, the study provides important insights for future research and practice.