A growing number of national diagnostic reference levels based on clinical indications (NDRL_ci) in CT have been implemented worldwide since the International Commission on Radiological Protection’s 2017 recommendation. This study aims to compare NDRL_ci practices, identify influencing factors and propose evidence-based recommendations for NDRL_ci development, based on the literature published between 1996 and 2025.

Systematic review.

A systematic literature search was conducted in PubMed, Web of Science and Scopus from 1996 to 24 august 2025. The Preferred Reporting Items for Systematic Reviews and Meta-Analysis framework was followed to report the study selection process in this review. Joanna Briggs Institute’s critical appraisal tools were used to evaluate the articles critically.

Adult patients undergoing CT scans for various clinical indications.

Clinical indication-based CT protocols with reported NDRL_ci values as CT dose index volume and dose length product (DLP).

The primary outcomes were NDRL_ci values reported for various clinical indications. The secondary outcomes were CT technology, protocol parameters and patient characteristics influencing NDRL_ci.

A total of 4146 articles were identified. 410 full texts were examined and 11 studies were included in the systematic review. 25 clinical indications across seven anatomical regions were identified across 11 included studies. The NDRL_ci for urinary stones and cerebrovascular accident had the highest number of references, while flank pain and occlusion had the lowest number. The highest NDRL_ci in DLP was found for total body CT in severe trauma (3830 mGy cm) and the lowest for sinusitis (70 mGy cm).

Several factors contribute to dose discrepancies for the same clinical indications in CT imaging, including kilovolt peak and milliampere-second, scan length, number of phases, patient size, reconstruction algorithm, CT scanner age and specifications, underscoring the need for standardised and optimised CT protocols. This review highlighted several challenges, which emphasise the importance of international organisations to standardise the development of NDRL_ci to improve comparability across countries.

CRD42024603574.

Frailty is a key predictor of adverse surgical outcomes in older adults, contributing to increased postoperative complications, prolonged hospitalisation and delayed recovery. Prehabilitation—targeting improvements in physical function before surgery—can mitigate these risks. However, traditional programmes often face low adherence due to logistical barriers. Integrating smart wearable devices into tele-supervised, home-based prehabilitation may enhance adherence, engagement and clinical outcomes.

This trial protocol describes the PREhabilitation of frail elderly PAtients undergoing majoR surgEry at HOME study with the objective to evaluate the effectiveness of a wearable-enhanced, tele-supervised prehabilitation programme (swSEP) versus standard care (unsupervised prehabilitation, uSEP) on improving preoperative functional capacity and postoperative outcomes in frail older adults undergoing major elective surgery.

This single-centre, prospective, randomised controlled trial will enrol 190 patients aged ≥65 years scheduled for major elective, non-cardiac surgery at Singapore General Hospital. Participants with frailty (Edmonton Frail Scale ≥6) will be randomised 1:1 to either the swSEP group (tele-supervised exercise with Fitbit Inspire 3 monitoring) or the uSEP group (standard physiotherapy education, exercise booklet and inspiratory muscle training if maximal inspiratory pressure 2O). The primary outcome is change in 6 min walk test distance from baseline to 1–3 days presurgery. Secondary outcomes include 30 s sit-to-stand test, handgrip strength, postoperative complications (per American College of Surgeons National Surgical Quality Improvement Program), hospital length of stay, readmissions, five-level version of the EuroQol five-dimensional questionnaire (EQ-5D-5L) and adherence. Data will be analysed using t-tests, analysis of covariance, logistic regression and Cox models, with stratification by baseline nutritional status.

Approved by the SingHealth Institutional Review Board (CIRB Ref: 2024/2242). Trial registered on ClinicalTrials.gov (NCT06633614). Results will be disseminated via peer-reviewed publications and academic conferences. Contact: irb@singhealth.com.sg

ClinicalTrials.gov Identifier: NCT06633614

Childhood obesity has surged globally, leading to various metabolic comorbidities and increased cardiovascular risks. Early intervention in lifestyle and feeding practices during infancy is crucial to mitigate these risks. This study evaluates the efficacy of a mobile web app-based intervention tool, named the Feeding, Lifestyle, Activity Goals (FLAGs) to promote healthier eating behaviours and lifestyle habits in infants from birth to 12 months.

This two-arm randomised controlled trial will enrol 220 caregiver-infant pairs per arm at KK Women’s and Children’s Hospital, Singapore, with recruitment expected from January to December 2025. Eligible participants include women at ≥34 weeks’ gestation or up to 3 days post delivery with pre-pregnancy overweight/obesity (body mass index (BMI) >23 kg/m²) and/or a diagnosis of diabetes. Caregiver-infant pairs will be randomised to the FLAGs intervention or control group. Over 12 months, both groups will receive standard infant care. The intervention group will undergo regular assessments via the FLAGs web app built-in assessment tool, assessing infant feeding practices, sedentary behaviour and physical activity. The intervention group will also receive FLAGs personalised guidance and weekly digital nudges. Maternal and infant data will be collected at baseline and at 12 months. Primary outcomes are infant BMI, weight-for-length and body composition at 12 months. Secondary outcomes include lifestyle behaviours and eating habits assessed through validated questionnaires when the infants are 1 year old. We will perform both intention-to-treat and per protocol analysis.

Ethical approval has been obtained from the SingHealth Centralised Institutional Review Board (Ref: 2024/3224). Written informed consent will be obtained from all participants. Study findings will be disseminated via peer-reviewed publications and academic conferences, with de-identified data available on reasonable request. This trial is registered on ClinicalTrials.gov (ID: NCT06457750).

NCT06457750.

Hospitalisation is one of the most stressful life events for older adults, particularly for those who are pre-frail or frail. Multi-component community-based interventions have the potential to address the complex needs of older adults post-acute care admission. While some available interventions have been developed with end-user engagement, fully involving older people who are pre-frail or frail in the design of interventions has been less common. Multi-component community-based interventions that address the needs of older adults and their care partners with potential implementation barriers informed by healthcare providers, community partners and health system decision makers are needed. This protocol paper describes the planned process of co-designing for older patients discharged into the community, a Post-Acute Care Intervention for Frailty using Information and Communication technology.

The development of a complex multi-component frailty intervention which meets older people’s needs involves several concurrent tasks and methodologies, each informed by co-design and conducted with consideration to eventual implementation. These tasks include: (1) establishing a Research Advisory Board, (2) assessing the feasibility and validity of using hospital administrative data to identify frail or pre-frail older adults and their needs, (3) conducting a needs assessment of patients returning to the community, (4) mapping community assets to identify existing programmes and services to help tailor the intervention, (5) co-designing a multicomponent frailty intervention, (6) selecting study outcome measures and (7) selecting and tailoring a digital health patient portal to support intervention delivery, data capture and communication.

Each task requiring ethics approval will be submitted to the Hamilton Integrated Research Ethics Board at McMaster University. Results will be disseminated through peer-reviewed journal articles, conferences and networks of relevant knowledge users who have the capacity to promote dissemination of the results. A toolkit will be developed to help researchers and healthcare providers replicate the methodology for other populations.