Zhang Melvyn

Dr. Zhang Melvyn

National Addictions Management Service
+1

Research Focus & Metrics

Academic Career Length

13Years (2014-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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20 June 2014 in BMC Psychiatry
Verified
Journal Article
Open access
PDF file
Roger HoRoger Ho
Roger Ho
Zhang MelvynZhang Melvyn
Zhang Melvyn
TTTammy Y Tsang
Tammy Y Tsang
ATAnastasia H Toh
Anastasia H Toh
FPFang Pan
Fang Pan
KMKwok-Kei Mak
Kwok-Kei Mak
This study evaluates the association between Internal Addiction (IA) and psychiatric co-morbidity in the literature. Meta-analyses were conducted on cross-sectional, case–control and cohort studies which examined the relationship between IA and psychiatric co-morbidity. Selected studies were extracted from major online databases. The inclusion criteria are as follows: 1) studies conducted on human subjects; 2) IA and psychiatric co-morbidity were assessed by standardised questionnaires; and 3) availability of adequate information to calculate the effect size. Random-effects models were used to calculate the aggregate prevalence and the pooled odds ratios (OR). Eight studies comprising 1641 patients suffering from IA and 11210 controls were included. Our analyses demonstrated a significant and positive association between IA and alcohol abuse (OR = 3.05, 95% CI = 2.14-4.37, z = 6.12, P < 0.001), attention deficit and hyperactivity (OR = 2.85, 95% CI = 2.15-3.77, z = 7.27, P < 0.001), depression (OR = 2.77, 95% CI = 2.04-3.75, z = 6.55, P < 0.001) and anxiety (OR = 2.70, 95% CI = 1.46-4.97, z = 3.18, P = 0.001). IA is significantly associated with alcohol abuse, attention deficit and hyperactivity, depression and anxiety.

12 April 2017 in Obesity Reviews
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Journal Article
Closed access
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YQYing‐Hui Quek
Ying‐Hui Quek
WTWilson Tam
Wilson Tam
Zhang MelvynZhang Melvyn
Zhang Melvyn
Roger HoRoger Ho
Roger Ho

28 August 2017 in Academic Psychiatry
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Journal Article
Closed access
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Zhang MelvynZhang Melvyn
Zhang Melvyn
RLRussell B. C. Lim
Russell B. C. Lim
CLCheng Lee
Cheng Lee
Roger HoRoger Ho
Roger Ho

21 February 2017 in Technology and Health Care
Verified
Journal Article
Closed access
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Zhang MelvynZhang Melvyn
Zhang Melvyn
Roger HoRoger Ho
Roger Ho

DCDoris Chia
Doris Chia
CNCharis Ng
Charis Ng
GKGomathinayagam Kandasami
Gomathinayagam Kandasami
MSMavis Y. L. Seow
Mavis Y. L. Seow
CCCarol Choo
Carol Choo
Zhang MelvynZhang Melvyn
Zhang Melvyn
This meta-analytic review aimed to examine the pooled prevalence rates of Internet addiction and gaming disorders in Southeast Asia. Several databases including PubMed, MEDLINE, PsycINFO, Web of Science, Embase, and Cochrane Central were searched and a total of 24 studies were included in this study. The selection of studies was conducted in accordance to the preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines. Two meta-analyses were conducted to examine data on Internet addiction and gaming disorders separately. A random-effects model was employed to derive the pooled prevalence rate. Mixed-effects meta-regression and subgroup analyses were performed to examine the moderators of the between-study heterogeneity. Publication bias was tested using the Egger’s regression test and funnel plot. Only seven out of the 11 Southeast Asian countries were represented in the literature. All except for two of the included studies were cross-sectional in nature. The findings revealed a pooled prevalence rate of 20.0% (95% confidence interval: 14.5%–27.0%) and 10.1% (95% confidence interval: 7.3%–13.8%) for Internet addiction and gaming disorders respectively. Mean age and study population were significant moderators of the between-study heterogeneity in the prevalence rates of gaming disorders such that samples involving older participants showed higher prevalence rate than those involving younger individuals. Country of study was found to be significant moderator of the between-heterogeneity for both Internet addiction and gaming disorders, however the findings should be interpreted with caution due to the small and unbalanced sample sizes. There was no significant publication bias. Such epidemiology research should be extended to the Southeast Asian countries that have not been studied or are under-studied. Given that the prevalence rates appear to be higher in Southeast Asia than in other world regions, future research should also explore the factors behind these inter-regional differences. Further longitudinal studies should also be conducted to examine the trajectories of such disorders.

6 January 2020 in Harm Reduction Journal
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Journal Article
Open access
PDF file
TLTuan Le
Tuan Le
TNTuan Anh Nguyen
Tuan Anh Nguyen
ADAnh Duc Dang
Anh Duc Dang
CNCuong Nguyen
Cuong Nguyen
HPHai Thanh Phan
Hai Thanh Phan
Zhang MelvynZhang Melvyn
Zhang Melvyn
Background: Methadone maintenance treatment (MMT) has been proven to be effective in treating opioid dependence. In Vietnam, MMT services are provided primarily by public clinics, with only one private MMT clinic established in recent years. Assessing the preferences of patients for different MMT models is important in evaluating the feasibility of these models. This study measured the preferences of drug users enrolling in public and private MMT clinics in Vietnam and examines the related factors of these preferences. Methods: A cross-sectional study was performed on 395 participants at 3 methadone clinics in Nam Dinh. Data about the preferences for MMT models and sociodemographic characteristics of participants were collected. Exploratory factor analysis was employed to explore the construct validity of the questionnaire. The chi-square test and Mann-Whitney test were used for analyzing demographic characteristics and preferences of participants. Multivariate logistic regression identified factors associated with participants’ preferences. Results: Half the participants received MMT treatment in a private facility (49.4%). Two preference dimensions were defined as “Availability and convenience of service” and “Competencies of clinic and health professionals”. Self-employed patients were more likely to consider these two dimensions when choosing MMT models. Only 9.9% of participants chose “Privacy” as one of the evaluation criteria for an MMT facility. Compared to public clinics, a statistically higher percentage of patients in the private clinic chose the attitudes of health workers as the reason for using MMT service (34.7% and 7.6% respectively). Mean score of satisfaction towards MMT services was 8.6 (SD = 1.0), and this score was statistically higher in a public facility, compared to the private facility (8.7 and 8.4 respectively). Conclusions: The study highlighted patterns of patient preferences towards MMT clinics. Compared to the public MMT model, the private MMT model may need to enhance their services to improve patient satisfaction.