Promoting the Participation of "Hard-to-Reach" Migrant Populations in Qualitative Public Health Research during the COVID-19 Pandemic in Chile.

The COVID-19 pandemic has further deepened socioeconomic and health inequities worldwide, especially among populations experiencing social vulnerability, such as international migrants. Sustained lockdowns and social distancing have raised challenges to conducting public health research with hard-to-reach populations. This study aims at exploring strategies to recruit "hard-to-reach" international migrants for qualitative public health research during the pandemic in Chile, based on the authors' experience. A retrospective qualitative evaluation process was carried out on the recruitment processes of three qualitative research projects focused on international migrants in Chile. All projects were implemented during the COVID-19 pandemic, demanding complementary and flexible strategies: (i) social media; (ii) snowball sampling; (iii) referrals from social workers and pro-migrant and migrant-led organizations; (iv) vaccination centers and healthcare centers; and (v) community-based recruitment. The strategies are qualitatively evaluated around seven emerging qualitative categories: (i) feasibility during lockdown periods; (ii) speed of recruitment; (iii) geographical coverage; (iv) sample diversity; (v) proportion of successful interviews; (vi) ethical considerations; and (vii) cost. Engaging hard-to-reach international migrants in public health research during the pandemic required constantly adapting recruitment strategies. Furthermore, relying on strategies that were not only Internet-based promoted the participation of populations with limited access to the Internet and low-digital literacy.

Respondent-driven sampling: Advantages and disadvantages from a sampling method. / Respondent-driven sampling: ventajas e inconvenientes de un método de muestreo.

This article summarizes the main elements, advantages, and disadvantages of Respondent-driven Sampling (RDS). Some criticisms regarding the feasibility of the inherent assumptions, their point estimators, and the obtained variances are pointed out. This article also comments on the problems observed in the quality of reports. Surveys using RDS should be methodologically sound as they are being applied to define priorities in health programs and develop national and international policies for financing service delivery, among other uses. However, there is considerable potential for bias related to implementation and analytical errors. There is limited empirical evidence on how representative the results obtained by RDS are, and the quest to improve the methodology is still in progress. Nevertheless, to have confidence in RDS results, we must verify that the social structure of the networks conforms to the assumptions required by the theory, that the sampling assumptions are reasonably fulfilled, and that the quality of the report is optimal, particularly for methodological and analytical items.

Este artículo resume algunas consideraciones, ventajas e inconvenientes de esta técnica de muestreo conocida como Respondent-driven Sampling (RDS). Se señalan algunas críticas que han aparecido en la literatura científica respecto a la viabilidad de los supuestos inherentes a esta técnica y, en consecuencia, respecto a los estimadores puntuales y de las varianzas así obtenidas. También, se comentan los problemas observados en la literatura acerca de la calidad de los reportes de este tipo de estudios. Las encuestas que utilizan RDS deben ser metodológicamente de buena calidad, pues están siendo aplicadas extensamente para definir prioridades de programas sanitarios, para desarrollar políticas nacionales e internacionales de financiamiento de prestación de servicios, entre otras aplicaciones. Sin embargo, existe un amplio potencial de sesgo al usar este método, muchos de los cuales están relacionados con la implementación y los errores analíticos. La evidencia empírica sobre cuán representativos son los resultados obtenidos mediante RDS es limitada, y la búsqueda para mejorar la metodología es un área de investigación aún en progreso. No obstante, para tener confianza en los resultados publicados debe verificarse que la estructura social de las redes estudiadas se ajusta a los supuestos requeridos por la teoría de RDS, que los supuestos del muestreo se cumplen razonablemente y que la calidad del reporte es óptima, en particular respecto a los ítems metodológicos y analíticos.

Factors associated with syphilis seroreactivity among polydrug users in Northeast Brazil: A cross-sectional study using Respondent Driven Sampling.

BACKGROUND: The burden of sexually transmitted infections (STIs), such as syphilis, is higher in low-income countries, with serious consequences and profound impact on sexual and reproductive health and human immunodeficiency virus (HIV) spread. Syphilis prevalence tend to be higher among people who misuse drugs than in the general population. OBJECTIVE: To assess syphilis and associated factors among polydrug users (PDU) in the city of Salvador, Northeast Brazil. METHODS: A cross-sectional study was conducted in 10 Brazilian cities between September and November 2009 using Respondent Driven Sampling (RDS). Participants answered an Audio Computer-Assisted Self Interview (ACASI) and were rapid tested for HIV and syphilis. We performed multivariable regression models for correlates of syphilis on Stata 10.0. Estimates were weighted by the inverse size of the individual social network size and homophily. RESULTS: Mean age was 29.3 years (range: 18-62), 74.0% were males, and 89.8% were non-white. Syphilis prevalence was 16.6%. Females (adjwOR:2.14; 95%CI:1.09-4.20), individuals over 29 years old (adjwOR:4.44; 95%CI:2.41-8.19), those who exchanged sex for money or drugs (adjwOR:3.51; 95%CI:1.84-6.71), "No/low" self-perceived risk of HIV infection (adjwOR:5.13; 95%CI:1.36-19.37), and having nine or less years of education (adjwOR:2.92; 95%CI:1.08-7.88) were associated with syphilis. CONCLUSION: One of the most pressing needs for syphilis prevention/control is the availability of rapid point-of-care diagnostic tests and treatment. Interventions should be tailored to PDU needs and their multiple burdens as shown in the present study, that may contribute to future studies aiming to better understand the relationships between drug use and syphilis.

Brief Client-Centered Motivational and Behavioral Intervention to Promote HPV Vaccination in a Hard-to-Reach Population: A Pilot Randomized Controlled Trial.

Objective To evaluate the impact of a client-centered behavioral intervention (Brief Negotiated Interviewing) on mothers' human papillomavirus (HPV) vaccine knowledge and vaccination initiation for their adolescent daughters. Methods We randomized mothers to intervention (n = 100) and control (n = 100) groups, and followed them over 12 months. Electronic medical records were reviewed to determine vaccination status. The primary outcome was receipt of the first vaccine. The secondary outcome was HPV vaccine knowledge among mothers. Results Brief Negotiated Interviewing intervention mothers demonstrated increased knowledge about HPV (pre/post mean score of 5 to 10 out of a possible 11; P < .001) and significantly higher mean knowledge scores (10 vs 6, P < .001) than control mothers. However, initiation and completion rates of the vaccine were not significantly different between groups. Conclusions Increasing HPV vaccine knowledge did not translate into increased vaccine uptake or completion of vaccination series. Future intervention must explore vaccine reminders to increase HPV vaccination rates.