Parameter identifiability of fundamental pharmacodynamic models

Issues of parameter identifiability of routinely used pharmacodynamics models are considered in this paper. The structural identifiability of 16 commonly applied pharmacodynamic model structures was analyzed analytically, using the input-output approach. Both fixed-effects versions (non-population, no between-subject variability) and mixed-effects versions (population, including between-subject variability) of each model structure were analyzed. All models were found to be structurally globally identifiable under conditions of fixing either one of two particular parameters. Furthermore, an example was constructed to illustrate the importance of sufficient data quality and show that structural identifiability is a prerequisite, but not a guarantee, for successful parameter estimation and practical parameter identifiability. This analysis was performed by generating artificial data of varying quality to a structurally identifiable model with known true parameter values, followed by re-estimation of the parameter values. In addition, to show the benefit of including structural identifiability as part of model development, a case study was performed applying an unidentifiable model to real experimental data. This case study shows how performing such an analysis prior to parameter estimation can improve the parameter estimation process and model performance. Finally, an unidentifiable model was fitted to simulated data using multiple initial parameter values, resulting in highly different estimated uncertainties. This example shows that although the standard errors of the parameter estimates often indicate a structural identifiability issue, reasonably “good” standard errors may sometimes mask unidentifiability issues

Indigenous Wāhine Talking Critically in the Museum Space

As greater numbers of community groups experience social disconnect, museums need to find better methods of engagement in order to remain relevant. We know that museums are no longer neutral spaces; in fact, they have a role to play in activism, which means they can shift their mission to support local communities celebrate and protect their Indigenous heritage (Drubay and Singhal 2020; Message 2018; Shelton 2013). What follows is a meditation by researchers in Aotearoa New Zealand who engage with Pacific-Indigenous concepts and museum practice in unique ways. Our big idea is to see “Oceania through Indigenous eyes” (Lagi-Maama 2019: 291) and, in particular, the eyes of Nālani Wilson-Hokowhitu with mo‘okū‘auhau to Kalapana, Hawai‘i, and Moloka‘i Nui a Hina; Maree Mills with whakapapa to Tongariro, Taupō, and Ngāti Tūwharetoa; and Rachel Yates, who hails from Vaisala, Sāmoa. As a collective, their curatorial talano kaōrero/mo‘olelo/stories connect to current debates in the museum world where local problems need local solutions. In this instance, Wilson-Hokowhitu and Mills share the ideas that shaped their mahi at Waikato Museum Te Whare Taonga o Waikato in Hamilton, and Yates has just finished a COVID-19 project as Curator of Pacific Cultures at the Museum of New Zealand Te Papa Tongarewa in Wellington.</jats:p

A school-based intervention ('Girls Active') to increase physical activity levels among 11- to 14-year-old girls: cluster RCT

Background: Physical activity (PA) levels among adolescent girls in the UK are low. ‘Girls Active’, developed by the Youth Sport Trust (YST), has been designed to increase girls’ PA levels. Objective: To understand the effectiveness and cost-effectiveness of the Girls Active programme. Design: A two-arm cluster randomised controlled trial. Setting: State secondary schools in the Midlands, UK. Participants: Girls aged between 11 and 14 years. Intervention: Girls Active involves teachers reviewing PA, sport and physical education provision, culture and practices in their school; attending training; creating action plans; and effectively working with girls as peer leaders to influence decision-making and to promote PA to their peers. Support from a hub school and the YST is offered. Main outcome measures: The change in objectively measured moderate to vigorous intensity PA (MVPA) levels at 14 months. Secondary outcomes included changes in overall PA level (mean acceleration), light PA levels, sedentary time, body composition and psychosocial outcomes. Cost-effectiveness and process evaluation (qualitative and quantitative) data were collected. Results: Twenty schools and 1752 pupils were recruited; 1211 participants provided complete primary outcome data at 14 months. No difference was found in mean MVPA level between groups at 14 months [1.7 minutes/day, 95% confidence interval (CI) –0.8 to 4.3 minutes/day], but there was a small difference in mean MVPA level at 7 months (2.4 minutes/day, 95% CI 0.1 to 4.7 minutes/day). Significant differences between groups were found at 7 months, but not at 14 months, in some of the objective secondary outcomes: overall PA level represented by average acceleration (1.39 mg, 95% CI 0.1 to 2.2 mg), after-school sedentary time (–4.7 minutes/day, 95% CI –8.9 to –0.6 minutes/day), overall light PA level (5.7 minutes/day, 95% CI 1.0 to 10.5 minutes/day) and light PA level on school days (4.5 minutes/day, 95% CI 0.25 to 8.75 minutes/day). Minor, yet statistically significant, differences in psychosocial measures at 7 months were found in favour of control schools. Significant differences in self-esteem and identified motivation in favour of intervention schools were found at 7 and 14 months, respectively. Subgroup analyses showed a significant effect of the intervention for those schools with higher numbers of pupils at 14 months. Girls Active was well received by teachers, and they reported that implemented strategies and activities were having a positive impact in schools. Barriers to implementation progress included lack of time, competing priorities and the programme flexibility. Implementation costs ranged from £2054 (£23/pupil) to £8545 (£95/pupil) per school. No differences were found between groups for health-related quality-of-life scores or frequencies, or for costs associated with general practitioner, school nurse and school counsellor use. Conclusions: Girls Active may not have had an effect on the random 90 girls per school included in the evaluation. Although we included a diverse sample of schools, the results may not be generalisable to all schools. Girls Active was viewed positively but teachers did not implement as many aspects of the programme as they wanted. The intervention was unlikely to have a wide impact and did not have an impact on MVPA level at 14 months. Capitalising on the opportunities of a flexible programme like this, while also learning from the stated barriers to and challenges of long-term implementation that teachers face, is a priority for research and practice. Trial registration: Current Controlled Trials ISRCTN10688342. Funding: This project was funded by the National Institute for Health Research (NIHR) Public Health Research programme and will be published in full in Public Health Research; Vol. 7, No. 5. See the NIHR Journals Library website for further project information. The YST funded the intervention. This study was undertaken in collaboration with the Leicester Clinical Trials Unit, a UK Clinical Research Collaboration-registered clinical trials unit in receipt of NIHR Clinical Trials Unit support funding. Neither the YST nor the NIHR Clinical Trials Unit had any involvement in the Trial Steering Committee, data analysis, data interpretation, data collection or writing of the report. The University of Leicester authors are supported by the NIHR Leicester–Loughborough Biomedical Research Unit (2012–17), the NIHR Leicester Biomedical Research Centre (2017–22) and the Collaboration for Leadership in Applied Health Research and Care East Midlands. These funders had no involvement in the Trial Steering Committee, the data analysis, data interpretation, data collection or writing of the report

Effectiveness of the ‘Girls Active’ school-based physical activity programme:A cluster randomised controlled trial

Abstract Background Globally, adolescent girls’ physical activity (PA) levels are low. The ‘Girls Active’ secondary school-based programme, developed by the Youth Sport Trust, aims to increase PA in adolescent girls. This paper explores the effectiveness of the ‘Girls Active’ school-based PA programme. Methods A random sample of girls aged 11–14 from 20 secondary schools (Midlands, UK) participated in a two-arm cluster randomised controlled trial. Ten schools received Girls Active and 10 continued with usual practice. Measurements were taken at baseline, seven- and 14-month follow-up. Primary outcome: wrist-worn accelerometer measured moderate- to vigorous-intensity PA (MVPA). Secondary outcomes: overall PA, light PA, sedentary time, body composition, and psychosocial outcomes. Generalised estimating equations, adjusted for school cluster and potential confounders, were used and A priori subgroup analysis was undertaken. Micro-costing and cost-consequence analyses were conducted using bespoke collection methods on programme delivery information. Outcomes for the cost-consequence analysis were health related quality of life measured by the Child Health Utility-9D and service use. Results Overall, 1752 pupils participated, 1211 (69.1%) provided valid 14-month accelerometer data. No difference in MVPA (mins/day; 95% confidence intervals) was found at 14 months (1.7; -0.8 to 4.3), there was at seven months (2.4; 0.1 to 4.7). Subgroup analyses showed significant intervention effects on 14-month in larger schools (3.9; 1.39 to 6.09) and in White Europeans (3.1; 0.60 to 6.02) and in early maturers (5.1; 1.69 to 8.48) at seven months. The control group did better in smaller schools at 14-months (-4.38; -7.34 to -1.41). Significant group differences were found in 14-month identified motivation (-0.09; -0.18 to -0.01) and at seven months in: overall PA (1.39 mg/day; 0.1 to 2.2), after-school sedentary time (-4.7; -8.9 to -0.6), whole day (5.7; 1.0 to 10.5) and school day (4.5; 0.25 to 8.75) light PA, self-esteem. Small, statistically significant, differences in some psychosocial variables favoured control schools. Micro-costing demonstrated that delivering the programme resulted in a range of time and financial costs at each school. Cost-consequence analysis demonstrated no effect of the programme for health related quality of life or service use. Conclusions Compared with usual practice, ‘Girls Active’ did not affect 14-month MVPA. Trial registration ISRCTN1068834

Diagnostic delay is common for patients with axial spondyloarthritis: Results from the National Early Inflammatory Arthritis Audit

OBJECTIVES: Updated guidelines for patients with axial SpA (axSpA) have sought to reduce diagnostic delay by raising awareness among clinicians. We used the National Early Inflammatory Arthritis Audit (NEIAA) to describe baseline characteristics and time to diagnosis for newly referred patients with axSpA in England and Wales. METHODS: Analyses were performed on sociodemographic and clinical metrics, including time to referral and assessment, for axSpA patients (n = 784) recruited to the NEIAA between May 2018 and March 2020. Comparators were patients recruited to the NEIAA with RA (n = 9270) or mechanical back pain (MBP; n = 370) in the same period. RESULTS: Symptom duration prior to initial rheumatology assessment was longer in axSpA than RA patients (P 6 months, compared with 33.7% of RA patients and 76.0% of MBP patients. Following referral, the median time to initial rheumatology assessment was longer for axSpA than RA patients (36 vs 24 days; P < 0.001) and similar to MBP patients (39 days; P = 0.30). Of the subset of patients deemed eligible for early inflammatory arthritis pathway follow-up, fewer axSpA than RA patients had disease education provided (77.5% vs 97.8%) and RA patients reported a better understanding of their condition and treatment. CONCLUSION: Diagnostic delay in axSpA remains a major challenge despite improved disease understanding and updated referral guidelines. Disease education is provided to fewer axSpA than RA patients, highlighting the need for specialist clinics and support programmes for axSpA patients

Development of an educational package for the universal human papillomavirus (HPV) vaccination programme: a co-production study with young people and key informants.

BACKGROUND: The English schools-based human papillomavirus (HPV) vaccination programme is routinely offered to all young people aged 12-13 years, to prevent cancers affecting the cervix, vulva, vagina, penis, anus and mouth. Lower uptake among some population groups has been identified, in part, because of unmet information needs among young people. To address these unmet needs we report intervention planning and development processes to co-produce an educational package about the HPV vaccine. METHODS: We used co-production research methodologies and the 'person-based approach' involving the following iterative stages: (i) collating and analysing primary and secondary evidence, including HPV vaccine communication materials, interviews and workshops; (ii) developing guiding principles; (iii) undertaking a behavioural analysis informed by the Behaviour Change Wheel and the Behaviour Change Technique taxonomy; (iv) development of a preliminary logic model; (v) co-production of resources, and; (vi) refinement of resources informed by feedback from young people and key informants. RESULTS: We co-produced EDUCATE, a theory-based educational package, that is designed to be delivered to young people prior to being offered the HPV vaccine to support uptake. Young people and key informants identified the following key issues to include as content: (i) HPV-related information; (ii) how vaccines work; (iii) safety and side-effects of the HPV vaccine; (iii) eligibility for the HPV vaccination programme, and; (iv) preparation of young people to receive the HPV vaccine. A manual for professionals (e.g. immunisation nurses, school staff) delivering the intervention and a PowerPoint presentation, interspersed with five short films, were co-produced with young people and key informants. Following feedback, the content of the EDUCATE package was refined to increase acceptability, engagement, and persuasiveness to the target users. CONCLUSION: Engagement with young people and key informants was integral to the development of our rigorously developed, theory-based intervention to address young people's information needs about the HPV vaccination programme. The acceptability and persuasiveness of the package has been maximised by working closely with young people and key informants to develop the content. An implementation study to examine how the EDUCATE package is implemented in practice and the impact on uptake of the HPV vaccination programme is underway

Micro-costing and a cost-consequence analysis of the 'Girls Active' programme : a cluster randomised controlled trial

Physical inactivity has been identified as a leading risk factor for premature mortality globally, and adolescents, in particular, have low physical activity levels. Schools have been identified as a setting to tackle physical inactivity. Economic evidence of school-based physical activity programmes is limited, and the costs of these programmes are not always collected in full. This paper describes a micro-costing and cost-consequence analysis of the 'Girls Active' secondary school-based programme as part of a cluster randomised controlled trial (RCT). Micro-costing and cost-consequence analyses were conducted using bespoke cost diaries and questionnaires to collect programme delivery information. Outcomes for the cost-consequence analysis included health-related quality of life measured by the Child Health Utility-9D (CHU-9D), primary care General Practitioner (GP) and school-based (school nurse and school counsellor) service use as part of a cluster RCT of the 'Girls Active' programme. Overall, 1,752 secondary pupils were recruited and a complete case sample of 997 participants (Intervention n = 570, Control n = 427) was used for the cost-consequence analysis. The micro-costing analysis demonstrated that, depending upon how the programme was delivered, 'Girls Active' costs ranged from £1,054 (£2 per pupil, per school year) to £3,489 (£7 per pupil, per school year). The least costly option was to absorb 'Girls Active' strictly within curriculum hours. The analysis demonstrated no effect for the programme for the three main outcomes of interest (health-related quality of life, physical activity and service use).Micro-costing analyses demonstrated the costs of delivering the 'Girls Active' programme, addressing a gap in the United Kingdom (UK) literature regarding economic evidence from school-based physical activity programmes. This paper provides recommendations for those gathering cost and service use data in school settings to supplement validated and objective measures, furthering economic research in this field