90 research outputs found
Coexistence of stationary Görtler and crossflow instabilities in boundary layers
No full textAuthor name used in this publication: 黃駿傑Author name used in this publication: 郝佳傲Author name used in this publication: 温志湧202502 bcchVersion of RecordRGCOthersNational Natural Science Foundation of ChinaPublishedVoR allowe
Leukotriene receptor antagonists and suicide: a self-controlled case series study
No full textAim/Objective: In March 2008 the suicide of a 15 year old boy captured media attention. The suicide was attributed to the
exposure of montelukast, a leukotriene receptor antagonist (LTRA) used to treat asthma and allergies. The presence of, unknown and
unmeasured confounders are limitations in observational studies, particularly in the study of suicide which has several risk factors.
The self-controlled case series (SCCS) method automatically controls for fi xed confounders.
Objectives: To investigate the association of suicide and LTRAs using the SCCS method in the UK.
Method: Electronic healthcare records of patients with a record of suicide attempt (including suicide and self -harm, poisoning-selfinfl
icted, injury–self infl icted, cause of overdose-deliberate) and exposure to LTRAs during the period of 1st January 1998 to 1st
January 2011 were extracted from the Health Improvement Network (THIN) database of anonymised records from contributing UK
general practices. A risk period of thirty days before and after exposure to LTRA and control periods within the observation time
of each patient were identifi ed. A Poisson analysis conditioned on the event was used to calculate the Incidence Rate Ratio (IRR).
Results: A total of 236 cases of fi rst attempts of suicide were identifi ed. The IRR for a risk period of 30 days after the start of
treatment with LTRA was 0.32 (95% CI 0.04-2.42; P=0.268).
Conclusion: Our study does not support the association between the use of LTRA and suicide attempts within the fi rst thirty days of
exposure to LTRA. Further studies with larger number of cases are needed
Coexistence of different mechanisms underlying the dynamics of supersonic turbulent flow over a compression ramp
No full textAuthor name used in this publication: 范建辉Author name used in this publication: 黄駿傑Author name used in this publication: 郝佳傲Author name used in this publication: 温志湧202409 bcchVersion of RecordRGCPublishedVoR allowe
A retrospective study of medical staff manpower and service demand in a Hong Kong Accident and Emergency Department
No full textMothers’ Preferences and Willingness to Pay for Human Papillomavirus Vaccination for Their Daughters: A Discrete Choice Experiment in Hong Kong
No full textObjectives: To determine the preference of mothers in Hong Kong and their willingness to pay (WTP) for human papillomavirus (HPV) vaccination for their daughters. Method: A discrete choice experiment survey with a two-alternative study design was developed. Data were collected from pediatric specialist outpatient clinics from 482 mothers with daughters aged between 8 and 17 years. Preferences of the four attributes of HPV vaccines (protection against cervical cancer, protection duration, side effects, and out-of-pocket costs) were evaluated. The marginal and overall WTP were estimated using multinomial logistic regression. A subgroup analysis was conducted to explore the impact of socioeconomic factors on mothers’ WTP. Results: Side effects, protection against cervical cancer, protection duration, and out-of-pocket cost determined the decision to receive or not receive the vaccine. All attributes had a statistically significant effect on the preference of and the WTP for the vaccine. Maximum WTP for ideal vaccines (i.e., 100% protection, lifetime protection duration, and 0% side effects) was HK1129). The estimated WTP for vaccines currently available was HK208), lower than the current market price. Among those who had a monthly household income of more than HK12,821), the WTP for vaccines currently offered was higher than the market price. Conclusions: This study provides new data on how features of the HPV vaccine are viewed and valued by mothers by determining their perception of ideal or improved and current vaccine technologies. These findings could contribute to future policies on the improvement of HPV vaccine and be useful for the immunization service in Hong Kong.postprin
Application of linear switched reluctance motors to precision position control
No full textAuthor name used in this publication: Norbert C. CheungVersion of RecordPublishedPublisher permissio
Normal range of osteoblastic activity in total hip arthroplasties on single-photon emission computed tomography bone scintigraphy
No full textAIM: Knowledge of the normal range of periprosthetic osteoblastic activity around total hip arthroplasties is required for rational diagnosis of complications. The aim of this study was to establish such a normal range for single-photon emission computed tomography (SPECT). Clinical utility of such a range is confident differentiation of normal from abnormal arthroplasties. METHODS: A total of 122 asymptomatic acetabular cups (age: 0-22 years) and 71 femoral stems (age: 0-20 years) were scanned with SPECT/CT. Two acetabular and three femoral activity ratios to normal reference bone were defined [acetabular axial (AA/RA), acetabular coronal (AC/RA), RA=reference acetabulum; femoral calcar (FC/RF), femoral mid-stem (FM/RF), femoral stem tip (FS/RF), RF=reference femur]. Upper cut-off of normal was defined as mean +3 SD (rounded). Two time breakpoints were analysed (12 and 24 months). RESULTS: The upper cut-off for the normal range was 1.0 for AA/RA, 1.5 for AC/RA and 2.2 for all thee of FC/RF, FM/RF and FS/RF. AA/RA, FM/RF and FS/RF showed no statistically significant temporal trends. AC/RA showed stabilization of activity after 12 months and FC/RF after 24 months. CONCLUSION: Measured activity ratios that fall within our normal range are likely to represent normal periprosthetic osteoblastic activity. Measured activity ratios that fall above the upper cut-offs of our normal range are likely to be abnormal. The cut-offs are robust in clinical practice and have utility in discriminating normal from abnormal stabilized arthroplasties where visual interpretation is ambiguous. Elevated AC/RA under 12 months and FC/RF under 24 months may represent normal periprosthetic activity and should be interpreted with caution.link_to_subscribed_fulltex
Advances in Epidemiological Methods and Utilisation of Large Databases: A Methodological Review of Observational Studies on Central Nervous System Drug Use in Pregnancy and Central Nervous System Outcomes in Children
No full textINTRODUCTION:
Studies have used various epidemiological approaches to study associations between central nervous system (CNS) drug use in pregnancy and CNS outcomes in children. Studies have generally focused on clinical adverse effects, whereas variations in methodologies have not received sufficient attention.
OBJECTIVE:
Our objective was to review the methodological characteristics of existing studies to identify any limitations and recommend further research.
METHODS:
A systematic literature search was conducted on observational studies listed in PubMed from 1 January 1946 to 21 September 2017. Following independent screening and data extraction, we conducted a review addressing the trends of relevant studies, differences between various data sources, and methods used to address bias and confounders; we also conducted statistical analyses.
RESULTS:
In total, 111 observational studies, 25 case-control studies, and 86 cohort studies were included in the review. Publications dating from 1978 to 2006 mainly focused on antiepileptic drugs, but research on antidepressants increased from 2007 onwards. Only one study focused on antipsychotic use during pregnancy. A total of 46 studies obtained data from an administrative database/registry, 20 from ad hoc disease registries, and 41 from ad hoc clinical samples. Most studies (58%) adjusted the confounding factors using general adjustment, whereas only a few studies used advanced methods such as sibling-matched models and propensity score methods; 42 articles used univariate analyses and 69 conducted multivariable regression analyses.
CONCLUSION:
Multiple factors, including different study designs and data sources, have led to inconsistent findings in associations between CNS drug use in pregnancy and CNS outcomes in children. Researchers should allow for study designs with clearly defined exposure periods, at the very least in trimesters, and use advanced confounding adjustment methodology to increase the accuracy of the findings.postprin
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