Methods Core Seminars

Upcoming seminars (2 events)

(First Event)

CAPS Methods Core Presents: How far will it be necessary to travel to eliminate HIV: the case of Malawi by Professor Sally Blower

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Professor Sally Blower

April 19 @ 12:00 pm – 1:00 pm PDT


Background: Malawi has a severe HIV epidemic: prevalence is 11%. Currently, treatment coverage is 67%; the governments’ goal is to reach UNAIDS’ target of 90% coverage by 2030 and eliminate HIV. The majority of the population live in rural communities at a low population density. We determine how long it will take all (i.e., diagnosed and undiagnosed) HIV-infected individuals in Malawi to travel to access treatment.

Methods: We construct a geographic accessibility map based on travel-time. To perform this analysis, we integrate three maps: a spatial map of the healthcare infrastructure, a density of infection (DoI) map, and a friction-surface map. We generated the DoI map by using geo-referenced HIV-testing data from ~16,000 individuals (15-49 years old) who participated in the 2015 Malawi Demographic and Health Survey, and demographic data from the WorldPop database. We generated the friction-surface map by overlaying a map of road and river networks with spatial data on land cover and topography. The friction-surface map shows the time it takes to travel across one grid of the map. Using the accessibility map, we calculated the functional relationship between the HIV epidemic and travel-time to access treatment.

Results: We find that, nation-wide, 90% of HIV-infected individuals can access treatment by traveling for ~80 minutes or less. However, healthcare in Malawi is decentralized into 28 healthcare districts; we find considerable inequities in access to treatment. In the most urban districts (Blantyre and Lilongwe) the travel-time for 90% of HIV-infected individuals is 35 minutes or less. In one of the most rural districts, Chitipa, travel-time is 160 minutes or less. Notably, we also find considerable differences among districts in the spatial distribution of their HIV epidemics: in the most urbanized districts the DoI is ~1,000 infected individuals/km2, in the most rural district there is only one infected individual/km2.

Conclusions: In order to reach UNAIDS’ target of 90% coverage, healthcare districts will need to address different challenges. Clinics in rural districts will need to employ strategies to minimize travel-times. Clinics in the most urbanized districts, due to their accessibility and the high DoI, may be overburdened in their ability to provide services.


Sally Blower, PhD, is a Professor in the David Geffen School of Medicine at the University of California at Los Angeles. She is a biomathematician and evolutionary biologist whose research focuses on developing models of transmission dynamics. She uses these models as health policy tools: to design epidemic control strategies for a variety of infectious diseases, to understand and predict the emergence of antibiotic and antiviral drug resistance, and to develop vaccination strategies. The main focus of her research is to develop the study of infectious diseases into a predictive science. Recently her work has focused on HIV, Syphilis, Genital Herpes, Smallpox, MRSA, Tuberculosis, Leprosy, Trachoma, and Influenza.

Please RSVP to Stuart Gaffney; also let him know if you are coming from outside Mission Hall and need to be put on the building security list. 

AmfAR Conference room MH-3700

550 16th Street (at 4th Street), 3nd Floor

Mission Bay, SF 94158


(Second Event)

This April, the Methods Core invites Sam Dilworth and Dee Chakravarty to present a discussion covering the survey software products Qualtrics and REDCap; these products are free to UCSF employees and could be the answer to your data collection needs!

In preparation for their seminar, they have crafted a brief online survey, where they hope to hear about your experiences with one or both of these products; it shouldn’t take more than 5 minutes to complete and your input is greatly appreciated!! The link to their short survey is here: short survey

Title:  To ‘Qualtrics’ or to ‘REDCap’? That is the question…

Presenters:  Samantha E. Dilworth, M.S. and Deepalika Chakravarty, M.S.

Center for AIDS Prevention Studies (CAPS)

Department of Medicine, UCSF

Date and Time: Friday, April 27, 2018, 11:00 am – 1:00 pm

Location: AmFAR Conference room, MH-3700 , 550 16th Street (at 4th Street), 3rd Floor, Mission Bay, SF 94158

Abstract:  As part of the MyResearch suite of applications, UCSF has made available two different online survey software packages: Qualtrics and Research Electronic Data Capture (REDCap). These applications are available to the UCSF Research Community and its collaborators at no extra cost. This talk will present an overview and comparison of these two applications by using examples of their real life implementation in research projects. Topics will include primary features, benefits, shortcomings, and IT-support options. The goal is to enable investigators and data analysis personnel to decide if one or both of these tools can be useful for their research studies. 


Sam Dilworth is a long-time CAPS statistician/data manager, having worked on a wide array of projects at CAPS and SFGH. Her adventures in HIV-prevention research run the gamut, from studies on a cohort of homeless women, to harm-reduction among meth-using MSM, to longitudinal research with gay couples. As a data manager, she has extensive experience with programming surveys, maintaining databases for, and producing analysis-ready datasets from multiple data collection/survey software packages, including Qualtrics, RedCAP, QDS, CASIC, and Survey Monkey. Her statistical qualifications afford her the benefit of knowing how best to capture the data in terms of how it is needed for data quality, precision, and analysis. She has consulted with and advised other researchers on survey software solutions; created protocols for survey testing, data collection, and data management; and is driven to find, master, and apply the best survey software available for the needs of the study.

Ms. Chakravarty is a biostatistician at CAPS experienced in survey programming, survey data management and statistical analyses of HIV related data from diverse populations. She has been the statistician and data manager on numerous longitudinal studies including multi-site HRSA-funded demonstration studies as well as NIMH-funded studies on gay couples. She has programmed and managed surveys for Computer Assisted Survey Instrument (CASI) administration using QDS, REDCap and Qualtrics. She has created databases to facilitate the day-to-day recruitment tracking and similar administrative aspects of longitudinal dyadic studies. She has also developed data collection and data management protocols, trained appropriate personnel and supervised data collection.

RSVP to Estie Hudes.


Materials from past seminars



  • February 6, 2018 – Ida Sim, MD, PhD (UCSF): Mobile apps and sensors to improve health and manage disease for populations and individuals interventions for marginalized populations
  • December 5, 2017 – Naihua Duan (Columbia University) and Richard Kravitz (UC Davis): ASA-sponsored webinar: “Small Data, N-of-1 Trials, and Personalized Medicine”
  • November 27, 2017 – Carl Latkin, PhD: Interactive workshop in developing and tailoring  social network instruments and social network behavior change interventions for marginalized population
  • April 20, 2017 – Bengt Muthen, Tihomir Asparouhov, and Ellen Hamaker:  ASA-sponsored webinar: Intensive Longitudinal Data Analysis Using Mplus
  • March 7, 2017 – David Benkeser, PhD:  Optimally Combining Outcomes To Improve Prediction
  • January 20, 2017 – Carl A. Latkin, PhD: Randomized clinical trials of social network approaches to HIV prevention and care: Lessons learned
  • May 17, 2016 —   John A. Schneider MD, MPH, PhD: Social Network Data Collection Approaches and Strategies for Introductory Analysis and Intervention PlanningVideo
  • May 3, 2016 — Tor Neilands, PhD, Kim Koester, MA & Troy Wood, MA: An Introduction to Survey Scale Development and Cognitive Interviewing
  • April 19-20, 2016 — Blair Johnson, PhD & Tania Huedo-Medina, PhD: Meta-Analysis workshop