1.The diagnostic performance of nuchal translucency alone as a screening test for Down syndrome: A systematic review and meta-analysis
Ma. Sergia Fatima P. Sucaldito ; John Jefferson V. Besa ; Lia M. Palileo-villanueva
Acta Medica Philippina 2025;59(Early Access 2025):1-17
BACKGROUND
Down syndrome or trisomy 21, the most common chromosomal disorder, results from the presence of a third copy of chromosome 21 and manifests as mild to moderate intellectual disability, growth retardation, congenital heart defects, gastrointestinal abnormalities, and characteristic facial features. Several methods have been used to screen for Down syndrome in the prenatal period, such as ultrasound, biomarkers, cell-free DNA testing, and combinations of these tests. A positive result from one or more of these screening tests signals the need for confirmatory karyotyping to clinch the diagnosis. Ultrasound between 11 to 14 weeks of gestation can evaluate nuchal translucency (NT) to screen for Down syndrome. During the second trimester, a triple or quadruple test can also be performed alone or in addition to NT to quantify Down syndrome risk. In limited resource settings however, only the measurement of NT via ultrasound can be performed since biomarker tests are either unavailable or inaccessible. While the diagnostic performance of NT measurement alone has been investigated in several observational studies, there is no consensus on its performance as a sole test to screen for Down syndrome.
OBJECTIVETo determine the diagnostic performance of NT during prenatal first-trimester ultrasound as a screening test for Down syndrome.
METHODSWe performed a systematic search on the PubMed, ProQuest, and Cochrane Library databases for recent systematic reviews and meta-analyses that addressed the objective. The existing reviews found were then independently appraised by the two reviewers with the AMSTAR-2 checklist. To update the existing reviews, a systematic search was done in the same databases to identify additional primary diagnostic studies, which were appraised using the QUADAS-2 tool. Random-effects univariate meta-analysis and summary receiving operator curve (HSROC) analysis for the outcomes were performed using Review Manager version 5.4 and R version 4.2.2, respectively. Subgroup analysis was performed by stratifying the baseline risk of mothers for fetal anomaly as low- or high-risk. Highrisk mothers were defined as women with risk factors such as advanced age, positive serum screen, presence of other ultrasound anomalies, and history of previous fetus with anomaly.
RESULTSWe found 22 cohort studies (n=225,846) of women at low-risk for fetal anomaly. The pooled sensitivity was 67.8% (95% CI: 61.4%-73.6%, I2=70.4%) and specificity was 96.3% (95% CI: 95.5%-96.9%, I2=96.7%). For low-risk women, the overall certainty of evidence was low, due to different modes of verification and heterogeneity not completely explained by variability in baseline risk or cut-points. Seven studies (n=9,197) were on high-risk women. The pooled sensitivity was 62.2% (95% CI: 54.1%-69.7%, I2=38.8%) and specificity was 96.5% (95% CI: 93.6%-98.1%, I2=95.5%). For women at high-risk, the evidence was rated as moderate due to differential verification.
CONCLUSIONOur analysis showed that NT measured through first-trimester ultrasound is specific for Down syndrome but has low sensitivity. Despite this, it is a useful screening test for Down syndrome in low-resource settings where other strategies may not be available or accessible. Furthermore, interpretation of NT results must take into consideration its limited sensitivity as this may lead to missed cases.
Human ; Nuchal Translucency Measurement ; Down Syndrome ; Sensitivity And Specificity
2.The diagnostic performance of nuchal translucency alone as a screening test for Down syndrome: A systematic review and meta-analysis.
Ma. Sergia Fatima P. SUCALDITO ; John Jefferson V. BESA ; Lia M. PALILEO-VILLANUEVA
Acta Medica Philippina 2025;59(15):7-23
BACKGROUND
Down syndrome or trisomy 21, the most common chromosomal disorder, results from the presence of a third copy of chromosome 21 and manifests as mild to moderate intellectual disability, growth retardation, congenital heart defects, gastrointestinal abnormalities, and characteristic facial features. Several methods have been used to screen for Down syndrome in the prenatal period, such as ultrasound, biomarkers, cell-free DNA testing, and combinations of these tests. A positive result from one or more of these screening tests signals the need for confirmatory karyotyping to clinch the diagnosis. Ultrasound between 11 to 14 weeks of gestation can evaluate nuchal translucency (NT) to screen for Down syndrome. During the second trimester, a triple or quadruple test can also be performed alone or in addition to NT to quantify Down syndrome risk. In limited resource settings however, only the measurement of NT via ultrasound can be performed since biomarker tests are either unavailable or inaccessible. While the diagnostic performance of NT measurement alone has been investigated in several observational studies, there is no consensus on its performance as a sole test to screen for Down syndrome.
OBJECTIVETo determine the diagnostic performance of NT during prenatal first-trimester ultrasound as a screening test for Down syndrome.
METHODSWe performed a systematic search on the PubMed, ProQuest, and Cochrane Library databases for recent systematic reviews and meta-analyses that addressed the objective. The existing reviews found were then independently appraised by the two reviewers with the AMSTAR-2 checklist. To update the existing reviews, a systematic search was done in the same databases to identify additional primary diagnostic studies, which were appraised using the QUADAS-2 tool. Random-effects univariate meta-analysis and summary receiving operator curve (HSROC) analysis for the outcomes were performed using Review Manager version 5.4 and R version 4.2.2, respectively. Subgroup analysis was performed by stratifying the baseline risk of mothers for fetal anomaly as low- or high-risk. Highrisk mothers were defined as women with risk factors such as advanced age, positive serum screen, presence of other ultrasound anomalies, and history of previous fetus with anomaly.
RESULTSWe found 22 cohort studies (n=225,846) of women at low-risk for fetal anomaly. The pooled sensitivity was 67.8% (95% CI: 61.4%-73.6%, I2=70.4%) and specificity was 96.3% (95% CI: 95.5%-96.9%, I2=96.7%). For low-risk women, the overall certainty of evidence was low, due to different modes of verification and heterogeneity not completely explained by variability in baseline risk or cut-points. Seven studies (n=9,197) were on high-risk women. The pooled sensitivity was 62.2% (95% CI: 54.1%-69.7%, I2=38.8%) and specificity was 96.5% (95% CI: 93.6%-98.1%, I2=95.5%). For women at high-risk, the evidence was rated as moderate due to differential verification.
CONCLUSIONOur analysis showed that NT measured through first-trimester ultrasound is specific for Down syndrome but has low sensitivity. Despite this, it is a useful screening test for Down syndrome in low-resource settings where other strategies may not be available or accessible. Furthermore, interpretation of NT results must take into consideration its limited sensitivity as this may lead to missed cases.
Human ; Nuchal Translucency Measurement ; Down Syndrome ; Sensitivity And Specificity
3.Development of the modified Safety Attitude Questionnaire for the medical imaging department.
Ravi Chanthriga ETURAJULU ; Maw Pin TAN ; Mohd Idzwan ZAKARIA ; Karuthan CHINNA ; Kwan Hoong NG
Singapore medical journal 2025;66(1):33-40
INTRODUCTION:
Medical errors commonly occur in medical imaging departments. These errors are frequently influenced by patient safety culture. This study aimed to develop a suitable patient safety culture assessment tool for medical imaging departments.
METHODS:
Staff members of a teaching hospital medical imaging department were invited to complete the generic short version of the Safety Attitude Questionnaire (SAQ). Internal consistency and reliability were evaluated using Cronbach's α. Confirmatory factor analysis (CFA) was conducted to examine model fit. A cut-off of 60% was used to define the percentage positive responses (PPR). PPR values were compared between occupational groups.
RESULTS:
A total of 300 complete responses were received and the response rate was 75.4%. In reliability analysis, the Cronbach's α for the original 32-item SAQ was 0.941. Six subscales did not demonstrate good fit with CFA. A modified five-subscale, 22-item model (SAQ-MI) showed better fit (goodness-to-fit index ≥0.9, comparative fit index ≥ 0.9, Tucker-Lewis index ≥0.9 and root mean square error of approximation ≤0.08). The Cronbach's α for the 22 items was 0.921. The final five subscales were safety and teamwork climate, job satisfaction, stress recognition, perception of management and working condition, with PPR of 62%, 68%, 57%, 61% and 60%, respectively. Statistically significant differences in PPR were observed between radiographers, doctors and others occupational groups.
CONCLUSION
The modified five-factor, 22-item SAQ-MI is a suitable tool for the evaluation of patient safety culture in a medical imaging department. Differences in patient safety culture exist between occupation groups, which will inform future intervention studies.
Humans
;
Surveys and Questionnaires
;
Patient Safety
;
Attitude of Health Personnel
;
Diagnostic Imaging
;
Reproducibility of Results
;
Male
;
Female
;
Adult
;
Job Satisfaction
;
Factor Analysis, Statistical
;
Middle Aged
;
Hospitals, Teaching
;
Safety Management
;
Organizational Culture
;
Medical Errors/prevention & control*
4.A machine learning approach for the diagnosis of obstructive sleep apnoea using oximetry, demographic and anthropometric data.
Zhou Hao LEONG ; Shaun Ray Han LOH ; Leong Chai LEOW ; Thun How ONG ; Song Tar TOH
Singapore medical journal 2025;66(4):195-201
INTRODUCTION:
Obstructive sleep apnoea (OSA) is a serious but underdiagnosed condition. Demand for the gold standard diagnostic polysomnogram (PSG) far exceeds its availability. More efficient diagnostic methods are needed, even in tertiary settings. Machine learning (ML) models have strengths in disease prediction and early diagnosis. We explored the use of ML with oximetry, demographic and anthropometric data to diagnose OSA.
METHODS:
A total of 2,996 patients were included for modelling and divided into test and training sets. Seven commonly used supervised learning algorithms were trained with the data. Sensitivity (recall), specificity, positive predictive value (PPV) (precision), negative predictive value, area under the receiver operating characteristic curve (AUC) and F1 measure were reported for each model.
RESULTS:
In the best performing four-class model (neural network model predicting no, mild, moderate or severe OSA), a prediction of moderate and/or severe disease had a combined PPV of 94%; one out of 335 patients had no OSA and 19 had mild OSA. In the best performing two-class model (logistic regression model predicting no-mild vs. moderate-severe OSA), the PPV for moderate-severe OSA was 92%; two out of 350 patients had no OSA and 26 had mild OSA.
CONCLUSION
Our study showed that the prediction of moderate-severe OSA in a tertiary setting with an ML approach is a viable option to facilitate early identification of OSA. Prospective studies with home-based oximeters and analysis of other oximetry variables are the next steps towards formal implementation.
Humans
;
Oximetry/methods*
;
Sleep Apnea, Obstructive/diagnosis*
;
Male
;
Female
;
Middle Aged
;
Machine Learning
;
Polysomnography
;
Adult
;
Anthropometry
;
ROC Curve
;
Aged
;
Algorithms
;
Predictive Value of Tests
;
Sensitivity and Specificity
;
Neural Networks, Computer
;
Demography
5.Health literacy and self-care among patients with chronic kidney disease in a primary care setting.
Han-Kwee HO ; Eileen Yi-Ling KOH ; Adina ABDULLAH ; Ngiap-Chuan TAN
Singapore medical journal 2025;66(6):307-313
INTRODUCTION:
The study objective was to determine the levels of self-care and health literacy (HL) and their associations among patients with chronic kidney disease (CKD).
METHODS:
This was a cross-sectional, questionnaire-based study conducted in a public primary care setting in Singapore. A total of 289 participants aged 21-80 years with hypertension were recruited. Self-care profiles were measured using the Hypertension Self-Care Profile (HTN-SCP; range 0-240, domain range 0-80). Health literacy was measured using the Short-Form Health Literacy Scale (HLS-SF12; range 0-50, limited literacy ≤33).
RESULTS:
The mean self-care score was 182.7 (standard deviation [SD] 23.2). The median HL score was 34.7 (interquartile range [IQR] 31.9-40.3), and 31.1% of participants had limited HL. Self-care was not associated with age, CKD status, household income and education, but was associated with gender and HL score. In the final regression model, lower HL scores (adjusted β = 1.03, 95% confidence interval [CI] 0.7 to 1.36, P < 0.001) and male gender (adjusted β = -5.29, 95% CI -10.56 to -0.03, P = 0.049) were associated with lower self-care scores. The HL scores were associated with self-care domains of self-efficacy (HL: β = 0.30, 95% CI 0.17 to 0.42, P < 0.001), motivation (HL: β = 0.40, 95% CI 0.26 to 0.53, P < 0.001) and behaviour (HL: β = 0.38, 95% CI 0.26 to 0.50, P < 0.001).
CONCLUSION
Thirty-one percent of the participants had limited HL. Self-care was not associated with age, race, CKD status, household income or education. Male gender and limited HL were associated with lower self-care. Self-care was associated with self-efficacy, motivation and behaviour. Future research could focus on more targeted approaches to improve self-care and HL among patients with CKD.
Humans
;
Male
;
Female
;
Health Literacy
;
Middle Aged
;
Self Care
;
Cross-Sectional Studies
;
Aged
;
Adult
;
Primary Health Care
;
Renal Insufficiency, Chronic/therapy*
;
Singapore
;
Surveys and Questionnaires
;
Aged, 80 and over
;
Young Adult
;
Hypertension/therapy*
6.Deploying artificial intelligence in the detection of adult appendicular and pelvic fractures in the Singapore emergency department after hours: efficacy, cost savings and non-monetary benefits.
John Jian Xian QUEK ; Oliver James NICKALLS ; Bak Siew Steven WONG ; Min On TAN
Singapore medical journal 2025;66(4):202-207
INTRODUCTION:
Radiology plays an integral role in fracture detection in the emergency department (ED). After hours, when there are fewer reporting radiologists, most radiographs are interpreted by ED physicians. A minority of these interpretations may miss diagnoses, which later require the callback of patients for further management. Artificial intelligence (AI) has been viewed as a potential solution to augment the shortage of radiologists after hours. We explored the efficacy of an AI solution in the detection of appendicular and pelvic fractures for adult radiographs performed after hours at a general hospital ED in Singapore, and estimated the potential monetary and non-monetary benefits.
METHODS:
One hundred and fifty anonymised abnormal radiographs were retrospectively collected and fed through an AI fracture detection solution. The radiographs were re-read by two radiologist reviewers and their consensus was established as the reference standard. Cases were stratified based on the concordance between the AI solution and the reviewers' findings. Discordant cases were further analysed based on the nature of the discrepancy into overcall and undercall subgroups. Statistical analysis was performed to evaluate the accuracy, sensitivity and inter-rater reliability of the AI solution.
RESULTS:
Ninety-two examinations were included in the final study radiograph set. The AI solution had a sensitivity of 98.9%, an accuracy of 85.9% and an almost perfect agreement with the reference standard.
CONCLUSION
An AI fracture detection solution has similar sensitivity to human radiologists in the detection of fractures on ED appendicular and pelvic radiographs. Its implementation offers significant potential measurable cost, manpower and time savings.
Humans
;
Singapore
;
Emergency Service, Hospital
;
Fractures, Bone/diagnostic imaging*
;
Artificial Intelligence
;
Retrospective Studies
;
Adult
;
Male
;
Female
;
Cost Savings
;
Middle Aged
;
Pelvic Bones/diagnostic imaging*
;
Reproducibility of Results
;
Aged
;
Sensitivity and Specificity
;
Radiography
7.Evidence gap between the systematic reviews and clinical concerns in acupuncture and moxibustion for frozen shoulder.
Zhen LUO ; Weijuan GANG ; Xiaoyi HU ; Huan CHEN ; Lu WANG ; Wencui XIU ; Tianyu MING ; Xianghong JING
Chinese Acupuncture & Moxibustion 2025;45(11):1673-1680
OBJECTIVE:
To reveal the gap between the evidence of systematic reviews (SRs) and clinical concerns by systematically summarizing the evidence on acupuncture and moxibustion for frozen shoulder and investigating the concerns and needs of clinicians in treatment with acupuncture and moxibustion for this disease.
METHODS:
The articles of SR and Meta-analysis on acupuncture and moxibustion for frozen shoulder were searched from CNKI, Wanfang, VIP, SinoMed, PubMed, EMbase and Cochrane Library, starting from the inception of each database up to December 31st, 2022. Two researchers screened the articles and extracted data independently. Using AMSTAR-2, the methodological quality of the included studies was evaluated. Based on systematic reviews and expert discussion, a questionnaire on clinical concerns of acupuncture and moxibustion for frozen shoulder was developed and distributed to clinicians. The discrepancies between the evidence and clinical concerns were compared from 5 dimensions, including population, interventions, control measures, outcome indicators and review time points.
RESULTS:
The evidence gaps existed between SRs and clinical concerns. In the existing studies, the needs of personalized treatment were not fully considered in terms of different syndromes/patterns of frozen shoulder and stages of illness, the outcome indicators were not employed properly, the time for outcome measurement was vague, the control groups were set up outside of standardization, and the methodological quality was lower.
CONCLUSION
It is suggested that future studies should improve the quality of methodology, lay more consideration to different patient groups, optimize outcome indicators and standardize the setting of control groups, so as to better meet the needs of patients and achieve the best match between evidence and clinicians' needs.
Humans
;
Acupuncture Therapy
;
Bursitis/therapy*
;
Evidence Gaps
;
Moxibustion
;
Systematic Reviews as Topic
;
Meta-Analysis as Topic
8.Health-related quality of life in Singapore: Population norms for the EQ-5D-5L and EORTC QLQ-C30.
Jaclyn TAN ; Mervyn Jr LIM ; Ravindran KANESVARAN ; Richard NORMAN ; Wen Yee CHAY ; Mohamad Farid Bin HARUNAL RASHID ; Mihir GANDHI ; Madeleine KING ; Nan LUO
Annals of the Academy of Medicine, Singapore 2025;54(3):147-159
INTRODUCTION:
Comparison of patient health-related quality of life (HRQOL) scores to a reference group is needed to quantify the HRQOL impact of disease or treatment. This study aimed to establish population norms for 2 HRQOL questionnaires-EuroQol 5-dimension 5-level questionnaire (EQ-5D-5L) and European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire-Core Question-naire 30 (EORTC QLQ-C30) according to age, sex and ethnicity-and to explore relationships between the EQ-5D-5L, EORTC QLQ-C30 and sociodemographic characteristics. We used a representative sample of adult Singapore residents aged 21 years and above.
METHOD:
This study used data collected from a cross-sectional household survey in which 600 adult Singaporeans completed questions on sociodemo-graphic characteristics-the EQ-5D-5L and the EORTC QLQ-C30. Multiple linear regression analyses were conducted to explore associations between sociodemographic characteristics, the EQ-5D-5L scores and the EORTC QLQ-C30 scores. Regression-based population norms were computed for each subgroup using a post-stratification method.
RESULTS:
In multiple linear regression analysis, age was significantly associated with EQ-5D-5L index and visual analogue scale (VAS) scores, while no sociodemographic characteristics were significantly associated with EORTC QLQ-C30 summary scores. The normative EQ-5D-5L index and VAS scores decreased in adults aged 65 years and above, and EQ-5D-5L index scores were slightly lower in females than males and in non-Chinese than Chinese. The normative EORTC QLQ-C30 summary scores were slightly higher in Chinese than in the non-Chinese group and in the 45-64 age group than other age groups.
CONCLUSION
This study provides population norms for the EQ-5D-5L and EORTC QLQ-C30 for the general adult population in Singapore. Future studies of patient populations in Singapore using EQ-5D-5L or QLQ-C30 can use these normative data to interpret the HRQOL data collected.
Humans
;
Quality of Life
;
Singapore
;
Male
;
Female
;
Middle Aged
;
Adult
;
Cross-Sectional Studies
;
Aged
;
Surveys and Questionnaires
;
Young Adult
;
Health Status
;
Age Factors
;
Linear Models
;
Aged, 80 and over
9.Machine learning to risk stratify chest pain patients with non-diagnostic electrocardiogram in an Asian emergency department.
Ziwei LIN ; Tar Choon AW ; Laurel JACKSON ; Cheryl Shumin KOW ; Gillian MURTAGH ; Siang Jin Terrance CHUA ; Arthur Mark RICHARDS ; Swee Han LIM
Annals of the Academy of Medicine, Singapore 2025;54(4):219-226
INTRODUCTION:
Elevated troponin, while essential for diagnosing myocardial infarction, can also be present in non-myocardial infarction conditions. The myocardial-ischaemic-injury-index (MI3) algorithm is a machine learning algorithm that considers age, sex and cardiac troponin I (TnI) results to risk-stratify patients for type 1 myocardial infarction.
METHOD:
Patients aged ≥25 years who presented to the emergency department (ED) of Singapore General Hospital with symptoms suggestive of acute coronary syndrome with no diagnostic 12-lead electrocardiogram (ECG) changes were included. Participants had serial ECGs and high-sensitivity troponin assays performed at 0, 2 and 7 hours. The primary outcome was the adjudicated diagnosis of type 1 myocardial infarction at 30 days. We compared the performance of MI3 in predicting the primary outcome with the European Society of Cardiology (ESC) 0/2-hour algorithm as well as the 99th percentile upper reference limit (URL) for TnI.
RESULTS:
There were 1351 patients included (66.7% male, mean age 56 years), 902 (66.8%) of whom had only 0-hour troponin results and 449 (33.2%) with serial (both 0 and 2-hour) troponin results available. MI3 ruled out type 1 myocardial infarction with a higher sensitivity (98.9, 95% confidence interval [CI] 93.4-99.9%) and similar negative predictive value (NPV) 99.8% (95% CI 98.6-100%) as compared to the ESC strategy. The 99th percentile cut-off strategy had the lowest sensitivity, specificity, positive predictive value and NPV.
CONCLUSION
The MI3 algorithm was accurate in risk stratifying ED patients for myocardial infarction. The 99th percentile URL cut-off was the least accurate in ruling in and out myocardial infarction compared to the other strategies.
Humans
;
Male
;
Female
;
Emergency Service, Hospital
;
Middle Aged
;
Electrocardiography
;
Machine Learning
;
Singapore
;
Chest Pain/blood*
;
Troponin I/blood*
;
Myocardial Infarction/blood*
;
Risk Assessment/methods*
;
Aged
;
Algorithms
;
Acute Coronary Syndrome/blood*
;
Adult
;
Sensitivity and Specificity
10.Development and validation of odour identification tests for olfactory assessment in Singapore.
Xinni XU ; Margaret Ru Xiang ZHANG ; Terese Huiying LOW ; Yew Kwang ONG
Annals of the Academy of Medicine, Singapore 2025;54(6):329-339
INTRODUCTION:
Odour recognition is influenced by culture. Odour identification tests need to be adapted to a population to accurately assess olfactory function. This study's objectives were to validate the Singapore version of the Sniffin' Sticks (SS-Sg) and a locally-developed odour recognition test (Scentsor) for Singapore.
METHOD:
This prospective study was performed in 3 otolaryngology outpatient clinics in 3 phases (1 May to 15 November 2024). Phase 1 was a survey evaluation of 93 odour descriptors to identify familiar odour descriptors to be used in the tests (n=414); Phase 2 evaluated and finalised SS-Sg and Scentsor to ensure test odours were recognised by ≥75% of healthy controls (n=130); and Phase 3 validated both tests on healthy controls (n=473) to obtain normative data, to determine test-retest reliability (n=50), and to assess the ability to distinguish patients with olfactory loss (n=67).
RESULTS:
In Phase 1, the unmodified SS blue and purple sets had 15/32 (46.9%) unfamiliar test odours and 25 unfamiliar distractors combined. In Phase 2, after modification, all odours in SS-Sg and Scentsor were correctly identified by ≥75% of controls. In Phase 3, normative data (age 21-83 years) was obtained. Both tests had good test-retest reliability (Pearson's correlation coefficient of 0.88 with<0.001 for SS-Sg; and at 0.90 with<0.001 for Scentsor). Both tests differentiated among normosmia, hyposmia and anosmia (SS-Sg scores: 12.6 [±2.4] versus [vs] 9.8 (±3.2) vs 6.0 [±2.3] respectively,<0.001; Scentsor scores: 14.3 [±1.8] vs 11.3 [±2.8] vs 5.8 [±3.4] respectively,<0.001).
CONCLUSION
SS-Sg and Scentsor have been validated to assess olfaction in Singapore.
Humans
;
Singapore
;
Male
;
Female
;
Odorants/analysis*
;
Middle Aged
;
Prospective Studies
;
Olfaction Disorders/diagnosis*
;
Adult
;
Reproducibility of Results
;
Aged
;
Smell/physiology*
;
Young Adult


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