Introduction: Accurate diagnosis of thyrotoxicosis, a condition resulting from excessive thyroid hormone activity, is essential for appropriate management. However, access to diagnostic tools such as thyrotropin receptor antibody (TRAb) assays and thyroid ultrasonography remains limited in resource-constrained settings, highlighting the need for cost-effective alternatives. Recent studies suggest that the free triiodothyronine to free thyroxine (FT3/FT4) ratio may serve as a potential biomarker for differentiating the causes of thyrotoxicosis. Methodology: This cross-sectional study evaluated the FT3/FT4 ratio in newly diagnosed thyrotoxicosis patients aged ≥18 years recruited from Hospital Tengku Ampuan Rahimah, Hospital Banting, Klinik Kesihatan Pelabuhan Klang, and Klinik Kesihatan Pandamaran between February and December 2025. All participants underwent thyroid function testing (FT3, FT4, and TSH) and autoantibody assessment (TRAb and anti-thyroid peroxidase [anti-TPO]). Diagnostic performance of the FT3/FT4 ratio for Graves’ disease was assessed using receiver operating characteristic (ROC) curve analysis. Results: Fifty-eight patients were included, of whom 58.6% were diagnosed with Graves’ disease. Patients with Graves’ disease had significantly higher FT3 levels (median 16.8 pmol/L; IQR 10.9–25.7) compared to those with non-Graves’ thyrotoxicosis (median 8.3 pmol/L; IQR 5.3–13.5; p <0.001), with similar trends observed for FT4 levels (p <0.001). However, the FT3/ FT4 ratio did not differ significantly between groups (p >0.05), with an overall ROC AUC of 0.572, indicating poor discriminatory ability. Subgroup analysis based on FT4 levels improved performance; at FT4 <30 pmol/L, the FT3/FT4 ratio demonstrated 75.0% sensitivity, 91.7% specificity, and 87.5% diagnostic accuracy at a cutoff of 0.3445 (AUC = 0.813; 95% CI: 0.570–1.000; p = 0.069). No significant association was observed between the FT3/FT4 ratio and TRAb or anti-TPO. Conclusion The FT3/FT4 ratio has limited overall diagnostic utility but may provide adjunctive value in selected biochemical contexts, particularly in settings with limited access to immunological testing.
Diagnosis, Differential ; Thyroxine ; Triiodothyronine ; Thyrotoxicosis ; Cross-Sectional Studies

UTILISATION OF THE WEB-BASED HOME ASSESSMENT TOOL AMONG PATIENTS WITH COVID-19 IN SELANGOR, MALAYSIA: AN OBSERVATIONAL STUDY Introduction: The COVID-19 pandemic has caused many countries to turn to web-based solutions. The Home Assessment Tool (HAT) is a web-based system using the MySejahtera application developed by the government. It serves as a communication platform for patients with COVID-19 to self-monitor their clinical symptoms and enables authorised healthcare personnel to access and manage collected data for clinical monitoring. Our study aimed to examine the utilisation of this internet-based tool among patients with COVID-19 in Selangor. Methods: This observational study analysed secondary data from the self-reported HAT within MySejahtera. It included all patients who were diagnosed with COVID-19 through molecular assays such as RT-PCR or RTK-Ag on 1–21 February 2021, aged ≥18 years and residing in Selangor. Patients who had documented their symptoms at least once in the HAT during the prescribed 10-day isolation period were classified as HAT users. Results: A total of 4438 patients were included, of whom 39.4% were HAT users, while 60.6% were non-HAT users. Logistic regression analysis revealed three significant factors associated with low utilisation of the HAT: absence of medical condition (odds ratio [OR]: 9.4; 95% confidence interval [CI]: 7.49–12.01), advanced age (OR: 1.35; 95% CI: 1.20–1.52) and non-Malaysian citizenship (OR: 3.4; 95% CI: 2.50–4.72). Conclusion: The utilisation of the HAT is low, which is associated with advanced age (≥65 years), absence of medical conditions and foreign nationality. It is imperative to develop inventive strategies tailored to address the unique needs of these particular demographics.