Chris Smith

Prof. Chris Smith

London School of Hygiene and Tropical Medicine, London WC1E 7HT, UK
+1
orcid

Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

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

Representative Publications

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1 December 2015 in Reproductive Health
Verified
Journal Article
Open access
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CSChris Smith
Chris Smith
UVUk Vannak
Uk Vannak
LSLy Sokhey
Ly Sokhey
TNThoai D. Ngo
Thoai D. Ngo
JGJudy Gold
Judy Gold
CFCaroline Free
Caroline Free
The objective of this paper is to outline the formative research process used to develop the MOTIF mobile phone-based (mHealth) intervention to support post-abortion family planning in Cambodia. The formative research process involved literature reviews, interviews and focus group discussions with clients, and consultation with clinicians and organisations implementing mHealth activities in Cambodia. This process led to the development of a conceptual framework and the intervention. Key findings from the formative research included identification of the main reasons for non-use of contraception and patterns of mobile phone use in Cambodia. We drew on components of existing interventions and behaviour change theory to develop a conceptual framework. A multi-faceted voice-based intervention was designed to address health concerns and other key determinants of contraception use. Formative research was essential in order to develop an appropriate mHealth intervention to support post-abortion contraception in Cambodia. Each component of the formative research contributed to the final intervention design.

26 June 2015 in Cochrane Database of Systematic Reviews
Verified
Journal Article
Open access
CSChris Smith
Chris Smith
JGJudy Gold
Judy Gold
TNThoai D Ngo
Thoai D Ngo
CSColin Sumpter
Colin Sumpter
CFCaroline Free
Caroline Free
Contraception provides significant benefits for women's and children's health, yet an estimated 225 million women had an unmet need for modern contraceptive methods in 2014. Interventions delivered by mobile phone have been demonstrated to be effective in other health areas, but their effects on use of contraception have not been established. To assess the effects of mobile phone-based interventions for improving contraception use. We searched for randomised controlled trials (RCTs) of client-provider interventions delivered by mobile phone to improve contraception use compared with standard care or another intervention. We searched the electronic databases Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, EMBASE, Global Health, PsycINFO, POPLINE, Africa-Wide Information and Latin American Caribbean Health Sciences Literature (LILACS) from January 1993 to October 2014, as well as clinical trials registries, online mHealth resources and abstracts from key conferences. Randomised controlled trials of mobile phone-based interventions to improve any form of contraception use amongst users or potential users of contraception. Outcome measures included uptake of contraception, measures of adherence, pregnancy and abortion. Two review authors independently screened titles and abstracts of studies retrieved using the search strategy and extracted data from the included studies. We calculated the Mantel-Haenszel risk ratio (RR) for dichotomous outcomes and the mean difference (MD) for continuous outcomes, together with 95% confidence intervals (CIs). Differences in interventions and outcome measures did not permit us to undertake meta-analysis. Five RCTs met our inclusion criteria. Three trials aimed to improve adherence to a specific method of contraception amongst existing or new contraception users by comparing automated text message interventions versus standard care. Two trials aimed to improve both uptake and adherence, not limited to one method, in both users and non-users of contraception. No trials were at low risk of bias in all areas assessed.One trial in the USA reported improved self reported oral contraceptive (OC) continuation at six months from an intervention comprising a range of uni-directional and interactive text messages (RR 1.19, 95% CI 1.05 to 1.35). One trial in Cambodia reported increased self reported use of effective contraception at four months post abortion from an intervention comprising automated interactive voice messages and phone counsellor support (RR 1.39, 95% CI 1.17 to 1.66).One feasibility trial in the USA reported a lower mean number of days between scheduled and completed attendance for the first but not subsequent Depo-Provera appointments using clinic records from an intervention comprising reminders and healthy self management text messages (mean difference (MD) -8.60 days, 95% CI -16.74 to -0.46). Simple text message OC reminders had no effect on missed pills as assessed by electronic medication monitoring in a small trial in the USA (MD 0.5 missed pills, 95% CI -1.08 to 2.08). No effect on self reported contraception use was noted amongst isotretinoin users from an intervention that provided health information via two uni-directional text messages and mail (RR 1.26, 95% CI 0.84 to 1.89). One trial assessed potential adverse effects of the intervention and reported no evidence of road traffic accidents or domestic abuse. Our review provides limited evidence that interventions delivered by mobile phone can improve contraception use. Whilst evidence suggests that a series of interactive voice messages and counsellor support can improve post-abortion contraception, and that a mixture of uni-directional and interactive daily educational text messages can improve OC adherence, the cost-effectiveness and long-term effects of these interventions remain unknown. Further high-quality trials are required to robustly establish the effects of interventions delivered by mobile phone to improve contraception use.

2 May 2025 in Nature Reviews Disease Primers
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Journal Article
Closed access
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SRSenaka Rajapakse
Senaka Rajapakse
NFNarmada Fernando
Narmada Fernando
Anou DreyfusAnou Dreyfus
Anou Dreyfus
CSChris Smith
Chris Smith
CRChaturaka Rodrigo
Chaturaka Rodrigo

15 October 2015 in Bulletin of the World Health Organization
Verified
Journal Article
Open access
CSChris Smith
Chris Smith
TNThoai D Ngo
Thoai D Ngo
JGJudy Gold
Judy Gold
PEPhil Edwards
Phil Edwards
UVUk Vannak
Uk Vannak
CFCaroline Free
Caroline Free
To assess the effect of a mobile phone-based intervention (mHealth) on post-abortion contraception use by women in Cambodia. The Mobile Technology for Improved Family Planning (MOTIF) study involved women who sought safe abortion services at four Marie Stopes International clinics in Cambodia. We randomly allocated 249 women to a mobile phone-based intervention, which comprised six automated, interactive voice messages with counsellor phone support, as required, whereas 251 women were allocated to a control group receiving standard care. The primary outcome was the self-reported use of an effective contraceptive method, 4 and 12 months after an abortion. Data on effective contraceptive use were available for 431 (86%) participants at 4 months and 328 (66%) at 12 months. Significantly more women in the intervention than the control group reported effective contraception use at 4 months (64% versus 46%, respectively; relative risk, RR: 1.39; 95% confidence interval, CI: 1.17-1.66) but not at 12 months (50% versus 43%, respectively; RR: 1.16; 95% CI: 0.92-1.47). However, significantly more women in the intervention group reported using a long-acting contraceptive method at both follow-up times. There was no significant difference between the groups in repeat pregnancies or abortions at 4 or 12 months. Adding a mobile phone-based intervention to abortion care services in Cambodia had a short-term effect on the overall use of any effective contraception, while the use of long-acting contraceptive methods lasted throughout the study period.

1 September 2022 in Clinical Infectious Diseases
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Journal Article
Open access
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TATakeshi Arashiro
Takeshi Arashiro
YAYuzo Arima
Yuzo Arima
HMHirokazu Muraoka
Hirokazu Muraoka
ASAkihiro Sato
Akihiro Sato
KOKunihiro Oba
Kunihiro Oba
MSMotoi Suzuki
Motoi Suzuki
Background: Although several coronavirus disease 2019 (COVID-19) vaccines initially showed high efficacy, there have been concerns because of waning immunity and the emergence of variants with immune escape capacity. Methods: A test-negative design case-control study was conducted in 16 healthcare facilities in Japan during the Delta-dominant period (August-September 2021) and the Omicron-dominant period (January-March 2022). Vaccine effectiveness (VE) against symptomatic severe acute respiratory syndrome coronavirus 2 infection was calculated for 2 doses for the Delta-dominant period and 2 or 3 doses for the Omicron-dominant period compared with unvaccinated individuals. Results: The analysis included 5795 individuals with 2595 (44.8%) cases. Among vaccinees, 2242 (55.8%) received BNT162b2 and 1624 (40.4%) received messenger RNA (mRNA)-1273 at manufacturer-recommended intervals. During the Delta-dominant period, VE was 88% (95% confidence interval [CI], 82–93) 14 days to 3 months after dose 2 and 87% (95% CI, 38–97) 3 to 6 months after dose 2. During the Omicron-dominant period, VE was 56% (95% CI, 37–70) 14 days to 3 months since dose 2, 52% (95% CI, 40–62) 3 to 6 months after dose 2, 49% (95% CI, 34–61) 6+ months after dose 2, and 74% (95% CI, 62–83) 14+ days after dose 3. Restricting to individuals at high risk of severe COVID-19 and additional adjustment for preventive measures (ie, mask wearing/high-risk behaviors) yielded similar estimates, respectively. Conclusions: In Japan, where most are infection-naïve, and strict prevention measures are maintained regardless of vaccination status, 2-dose mRNA vaccines provided high protection against symptomatic infection during the Delta-dominant period and moderate protection during the Omicron-dominant period. Among individuals who received an mRNA booster dose, VE recovered to a high level.

14 April 2020 in Tropical Medicine and Health
Verified
Journal Article
Open access
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EEEdna M. Edrada
Edna M. Edrada
ELEdmundo B. Lopez
Edmundo B. Lopez
JVJose Benito Villarama
Jose Benito Villarama
EVEumelia P. Salva Villarama
Eumelia P. Salva Villarama
BDBren F. Dagoc
Bren F. Dagoc
RSRontgene M. Solante
Rontgene M. Solante
Background: The novel coronavirus (COVID-19) is responsible for more fatalities than the SARS coronavirus, despite being in the initial stage of a global pandemic. The first suspected case in the Philippines was investigated on January 22, 2020, and 633 suspected cases were reported as of March 1. We describe the clinical and epidemiological aspects of the first two confirmed COVID-19 cases in the Philippines, both admitted to the national infectious disease referral hospital in Manila.Case presentation: Both patients were previously healthy Chinese nationals on vacation in the Philippines travelling as a couple during January 2020. Patient 1, a 39-year-old female, had symptoms of cough and sore throat and was admitted to San Lazaro Hospital in Manila on January 25. Physical examination was unremarkable.Influenza B, human coronavirus 229E,Staphylococcus aureusandKlebsiella pneumoniaewere detected by PCR on initial nasopharyngeal/oropharyngeal (NPS/OPS) swabs. On January 30, SARS-CoV-2 viral RNA was reported to be detected by PCR on the initial swabs and she was identified as the first confirmed COVID-19 case in the Philippines. Her symptoms resolved, and she was discharged. Patient 2, a 44-year-old male, had symptoms of fever, cough, and chills.Influenza BandStreptococcus pneumoniaewere detected by PCR on initial NPS/OPS swabs. He was treated for community-acquired pneumonia with intravenous antibiotics, but his condition deteriorated and he required intubation. On January 31, SARS-CoV-2 viral RNA was reported to be detected by PCR on the initial swabs, and he was identified as the 2nd confirmed COVID-19 infection in the Philippines. On February 1, the patient’s condition deteriorated, and following a cardiac arrest, it was not possible to revive him. He was thus confirmed as the first COVID-19 death outside of China.Conclusions: This case report highlights several important clinical and public health issues. Despite both patients being young adults with no significant past medical history, they had very different clinical courses, illustrating how COVID-19 can present with a wide spectrum of disease. As of March 1, there have been three confirmed COVID-19 cases in the Philippines. Continued vigilance is required to identify new cases.