Trading HIV for sheep: Risky sexual behavior and the response of female sex workers to Tabaski in Senegal.

We use a cohort of female sex workers (FSWs) in Senegal to show how large anticipated economic shocks lead to increased risky sexual behavior. Exploiting the exogenous timing of interviews, we study the effect of Tabaski, the most important Islamic festival celebrated in Senegal, in which most households purchase an expensive animal for sacrifice. Condom use, measured robustly via the list experiment, falls by between 27.3 percentage points (pp) (65.5%) and 43.1 pp (22.7%) in the 9 days before Tabaski, or a maximum of 49.5 pp (76%) in the 7 day period preceding Tabaski. The evidence suggests the economic pressures from Tabaski are key to driving the behavior change observed through the price premium for condomless sex. Those most exposed to the economic pressure from Tabaski were unlikely to be using condoms at all in the week before the festival. Our findings show that Tabaski leads to increased risky behaviors for FSWs, a key population at high risk of HIV infection, for at least 1 week every year and has implications for FSWs in all countries celebrating Tabaski or similar festivals. Because of the scale, frequency, and size of the behavioral response to shocks of this type, policy should be carefully designed to protect vulnerable women against anticipated shocks.

Can Self-affirmation Encourage HIV-Prevention? Evidence from Female Sex Workers in Senegal.

We test an intervention aiming to increase condom usage and HIV testing in a stigmatized population at high risk of contracting HIV: female sex workers (FSWs) in Senegal. Some sex work is legal in Senegal, and condoms and HIV tests are freely available to registered FSWs-but FSWs may be reluctant to get tested and use condoms, in part because doing so would entail acknowledging their risk of contracting HIV and potentially expose them to stigma. Drawing on self-affirmation theory, we hypothesized that reflecting on a source of personal pride would help participants acknowledge their risk of HIV, intend to use condoms more frequently, and take an HIV test. Prior research suggests that similar self-affirmation interventions can help people acknowledge their health risks and improve their health behavior, especially when paired with information about effectively managing their health (i.e., self-efficacy information). However, such interventions have primarily been tested in the United States and United Kingdom, and their generalizability outside of these contexts is unclear. Our high-powered experiment randomly assigned participants (N = 592 FSWs; N = 563 in the final analysis) to a self-affirmation condition or a control condition and measured their risk perceptions, whether they took condoms offered to them, and whether (after randomly receiving or not receiving self-efficacy information) they took an HIV test. We found no support for any of our hypotheses. We discuss several explanations for these null results based on the stigma attached to sex work and HIV, cross-cultural generalizability of self-affirmation interventions, and robustness of previous findings.

InterMob: a 24-month randomised controlled trial comparing the effectiveness of an intervention including behavioural change techniques and free transport versus an intervention including air pollution awareness-raising on car use reduction among regular car users living in Grenoble, France.

BACKGROUND: Frequent car use contributes to health and environmental issues such as air pollution, climate change and obesity. Active and sustainable mobility (bike, walk, public transport, car sharing) may address these issues. Different strategies have been implemented in past research, involving hard levers, aimed at modifying the economical or geographical context (e.g., free public transport), and soft levers, aimed at modifying psychological processes (e.g., personalised transport advice). However, few studies have combined both hard and soft levers. In addition, few have used robust methodologies (e.g., randomised controlled trials), followed behavioural changes in the long-term, and been anchored in behaviour change theories. InterMob aims to address these limits by implementing a 24-month randomised controlled trial including hard and soft levers. The objectives of InterMob are to a) evaluate the effectiveness of an experimental arm versus an active controlled arm, and b) identify the processes of mobility change. METHODS: Regular car users living in Grenoble (N = 300) will be recruited and randomised to one of the two arms. The experimental arm consists in a six-month intervention combining hard levers (free access to transport/bikes), and soft levers (e.g., personalised transport advice). The control arm consists in a six-month intervention aimed at raising awareness on air pollution and its health effects. Both arms will include eight evaluation weeks (spread out over 24 months) based on a GPS, an accelerometer, and a pollution sensor. Moreover, participants will complete mobility logbooks and surveys measuring psychological constructs, socio-economical, and socio-spatial characteristics. DISCUSSION: InterMob will assess the effectiveness of two interventions aimed at reducing car use within regular car users in the short-, mid- and long-term. Moreover, InterMob will allow to better understand the psychological processes of behaviour change, and the socio-economical and geographical conditions under which the intervention is efficient in reducing car use. Finally, the benefits of mobility change in terms of physical activity, quality of life, and exposure to pollution will be quantified. TRIAL REGISTRATION: ClinicalTrials.gov : NCT05096000 on 27/10/2021 (retrospectively registered).

Estimating misreporting in condom use and its determinants among sex workers: Evidence from the list randomisation method.

Social desirability bias, which is the tendency to underreport socially undesirable health behaviours, significantly distorts information on sensitive behaviours gained from self-reports. We applied the list randomisation method to indirectly elicit condom use among female sex workers and tested it among 651 female sex workers in Senegal, a country where sex workers face high social stigma and where the AIDS epidemic is mainly concentrated among this population. On the basis of our list randomisation, we found that the condom use rate in the last sexual intercourse with a client was 78%, which is significantly lower than the 97% obtained when asked directly in the survey. When estimating condom use among the subgroups, we found that female sex workers who are at a higher risk of infection are less likely to use condoms.

The effect of sex work regulation on health and well-being of sex workers: Evidence from Senegal.

Senegal is the only African country where sex work is legal and regulated by a health policy. Senegalese female sex workers (FSWs) are required to register with a health facility and to attend monthly routine health checks aimed at testing and treating sexually transmitted infections (STIs). Compliance to those routine visits is recorded on a registration card that must be carried by FSWs in order to avoid sanctions in case of police arrests. Although this policy was first introduced in 1969 to limit the spread of STIs, there is no evidence so far of its impact on FSWs' health and well-being. The paper aims to fill this gap by exploiting a unique data set of registered and unregistered Senegalese FSWs. Using propensity score matching, we find that registration has a positive effect on FSWs' health. However, we find that registration reduces FSWs' subjective well-being. This finding is explained by the fact that registered FSWs are found to engage in more sex acts, in riskier sex acts, have less social support from their peers, and are more likely to experience violence from clients and police officers. We prove that those results are robust to the violation of the conditional independence assumption, to misspecification of the propensity score model, and that covariate balance is achieved. The results suggest that more efforts should be deployed to reduce the stigma associated with registration and to address the poor well-being of FSWs, which is counterproductive to HIV prevention efforts.

Validation of a short-form questionnaire to check patients' adherence to antibiotic treatments in an outpatient setting.

Antimicrobial resistance challenge requests to be able to measure patient medication-adherence in outpatient setting, where more than 90% of antibiotics are prescribed. We take advantage of an original dataset where adherence to treatment has been measured through two alternative measurements: pills count and the Morisky scale. Considering the first measure as benchmark, we test the validity of each of the Morisky items and their composition in a synthetic scale. We show that the short-form version of the medication-adherence scale with three items has the best predictive properties in the domain of antibiotic treatments. Given its concision, this tool could even be used by clinicians to quickly assess patients' adherence and modify it in the course, when needed.

Determinants of road traffic crash fatalities across Indian States.

This article explores the determinants of road traffic crash fatalities in India. In addition to income, the analysis considers the sociodemographic population structure, motorization levels, road and health infrastructure and road rule enforcement as potential factors. An original panel data set covering 25 Indian states is analyzed using multivariate regression analysis. Time and state fixed-effects account for unobserved heterogeneity across states and time. The rising motorization, urbanization and accompanying increase in the share of vulnerable road users, that is, pedestrians and two-wheelers, are the major drivers of road traffic crash fatalities in India. Among vulnerable road users, women form a particularly high-risk group. Higher expenditure per police officer is associated with a lower fatality rate. The results suggest that India should focus, in particular, on road infrastructure investments that allow the separation of vulnerable from other road users on improved road rule enforcement and should pay special attention to vulnerable female road users.

Reforming the registration policy of female sex workers in Senegal? Evidence from a discrete choice experiment.

Evidence suggests that treating sexually transmitted infections (STIs) amongst female sex workers (FSWs) is a cost-effective strategy to reduce the spread of HIV/AIDS. Senegal is the only African country where sex work is regulated by a public health policy which aims to monitor and routinely treat STIs. The law requires FSWs to be at least 21 years old, register with a health centre and the police, carry an up-to-date registration booklet, attend monthly health check-ups, and test negative for STIs. Despite health and legal benefits of registration, 80% of FSWs in Senegal are not registered. Hence, the potential health benefits of the policy have not materialised. To understand why FSWs do not want to register and to define policy changes that would increase the registration rate of FSWs in Senegal, we designed and implemented a discrete choice experiment (DCE) completed by 241 registered and 273 non-registered FSWs. Participants made choices between a series of hypothetical but realistic registration policy changes. Conditional logit models were used to analyse the DCE data. The results highlighted that confidentiality at the health facility was an important element, registered and non-registered FWs were respectively 26.0 percentage points (pp) and 22.1 pp more likely to prefer a policy that guaranteed confidentiality at the health centre. Similarly, both groups preferred a policy where their health record was only held at the health centre and not with the police. Several interventions to increase FSW registration rate and improve their wellbeing may be implemented without modifying the law. For example, the introduction of psychosocial support in the registration policy package, replacing the registration booklet by a QR code, the use of electronic medical files and the integration of FSWs routine visits with maternal health appointments to increase confidentiality have the potential to encourage registration of FSWs.

From a drought to HIV: An analysis of the effect of droughts on transactional sex and sexually transmitted infections in Malawi.

Each year there are over 300 natural disasters globally with millions of victims that cost economic losses near USD$100 billion. In the context of climate change, an emerging literature linking extreme weather events to HIV infections suggests that efforts to control the HIV epidemic could be under threat. We used Demographic and Health Survey (DHS) data collected during the 2015-2016 harsh drought that affected several areas of Malawi to provide new evidence on the effect of an unanticipated economic shock on sexual behaviours of young women and men. We find that amongst women employed in agriculture, a six-months drought doubles their likelihood of engaging in transactional sex compared to women who were not affected by the drought and increases their likelihood of having a sexually transmitted infections (STI) by 48% in the past twelve months. Amongst men employed outside of agriculture, drought increases by 50% the likelihood of having a relationship with a woman engaged in transactional sex. These results suggest that women in agriculture experiencing economic shocks as a result of drought use transactional sex with unaffected men, i.e. men employed outside agriculture, as a coping mechanism, exposing themselves to the risk of contracting HIV. The effect was especially observed among non-educated women. A single drought in the last five years increases HIV prevalence in Malawi by around 15% amongst men and women. Overall, the results confirm that weather shocks are important drivers of risky sexual behaviours of young women relying on agriculture in Africa. Further research is needed to investigate the most adequate formal shock-coping strategies to be implemented in order to limit the negative consequences of natural disasters on HIV acquisition and transmission.

Risk aversion and HIV/AIDS: Evidence from Senegalese female sex workers.

HIV/AIDS is the second cause of mortality globally and there are 5000 new infections each day. Globally, sex workers are 13 times more at risk of HIV than the general population and in Senegal they have an HIV prevalence 16.5 times greater. Therefore, it is urgent to encourage behaviour change, which requires a better understanding of the reasons why sex workers engage in risky behaviours. We provide new evidence of the role of risk preferences on sexual behaviours, health behaviours and health outcomes of 600 female sex workers in Senegal in July and August 2017. We measure risk aversion of sex workers using an incentivised Gneezy and Potters task in addition to specific risk-taking scales in four domains (in general, finance, health and sex). Understanding of the experimental task was high despite low literacy level of participants. Using ordinary least squares, we find that risk aversion is an important predictor of sex workers' sexual behaviours. We find that sex workers with higher level of risk aversion have less sex acts with clients, have less clients at risk of HIV, are more likely to engage in protected sex acts and as a result earn less money per sex act. Furthermore, we find that sex workers exhibiting higher level of risk aversion are less likely to be infected with sexually transmitted infections. Results highlight that some associations between risk preferences and sexual and health behaviours are domain specific. To conclude, our results confirm the role of risk preferences in the spread of HIV/AIDS epidemic and suggest the importance of collecting information on self-reported risk aversion to identify individuals who are at a greater risk of HIV/AIDS. Finally, our results provide some rationale in using lottery-based financial incentives to prevent sexually transmitted infections and HIV/AIDS among high-risk populations.

Nothing but the truth: Consistency and efficiency of the list experiment method for the measurement of sensitive health behaviours.

RATIONALE: Social desirability bias, which is the tendency to under-report socially, undesirable health behaviours, significantly distorts information on sensitive behaviours, gained from self-reports and prevents accurate estimation of the prevalence of those, behaviours. We contribute to a growing body of literature that seeks to assess the performance of the list experiment method to improve estimation of these sensitive health behaviours. METHOD: We use a double-list experiment design in which respondents serve as the treatment group for one list and as the control group for the other list to estimate the prevalence of two sensitive health behaviours in different settings: condom use among 500 female sex workers in urban Senegal and physical intimate partner violence among 1700 partnered women in rural Burkina Faso. First, to assess whether the list experiment improves the accuracy of estimations of the prevalence of sensitive behaviours, we compare the prevalence rates estimated from self-reports with those elicited through the list experiment. Second, we test whether the prevalence rates of the sensitive behaviours obtained using the double-list design are similar, and we estimate the reduction in the standard errors obtained with this design. Finally, we compare the results obtained through another indirect elicitation method, the polling vote method. RESULTS: We show that the list experiment method reduces misreporting by 17 percentage points for condom use and 16-20 percentage points for intimate partner violence. Exploiting the double-list experiment design, we also demonstrate that the prevalence estimates obtained through the use of the two lists are identical in the full sample and across sub-groups and that the double-list design reduces the standard errors by approximately 40% compared to the standard errors in the simple list design. Finally, we show that the list experiment method leads to a higher estimation of the prevalence of sensitive behaviours than the polling vote method. CONCLUSION: The study suggests that list experiments are an effective method to improve estimation of the prevalence of sensitive health behaviours.

HIV infection risk and condom use among sex workers in Senegal: evidence from the list experiment method.

Social desirability bias, which is the tendency to under-report socially undesirable health behaviours, significantly distorts information on sensitive behaviours that is gained from self-reports. As a result, self-reported condom use among high-risk populations is thought to be systematically over-reported, and it is impossible to identify the determinants of condom use. The main objective of the article is to elicit unbiased information on condom use among female sex workers (FSWs) using the double list experiment method to analyse the role of HIV infection and exposure to HIV prevention methods in condom use. More specifically, the difference in levels of condom use between HIV-positive and HIV-negative FSWs is estimated. In addition, the role of FSWs' registration and participation in a pre-exposure prophylaxis (PrEP) demonstration project in condom use is considered. A list experiment was designed to elicit condom use information from 786 FSWs in Senegal who were surveyed in 2015 and 2017. Using the list experiment method, participants were randomly assigned to one of two groups (treatment or control) and were asked to report the number of statements they agreed with. Respondents assigned to the control group were presented with three non-sensitive items, whereas those allocated to the treatment group were presented with the same three statements plus the sensitive item (e.g. 'I used a condom during my last intercourse with a client'). Comparing the average number of sentences that were agreed with in both groups provides an estimation of the condom use rate in the treatment group and estimating such prevalence for several sub-groups allows the role of HIV infection risk in condom use to be identified. The percentage of FSWs using condoms in their last sexual intercourse with a client was 80% in 2015 and 78% in 2017, which was significantly lower than the 97% obtained in the face-to-face surveys in both waves. When estimating condom use among sub-groups with the list experiment method, we found that condom use among HIV-positive FSWs was only 34%, which was 47 percentage points lower than condom use among HIV-negative FSWs. We also found that registered FSWs are more likely to use condoms than clandestine FSWs. However, we did not find any difference in condom use between FSWs who were enrolled in the PrEP demonstration project and those who were not enrolled. Health policies should therefore aim to increase condom use among HIV-positive FSWs.

The expected and unexpected benefits of dispensing the exact number of pills.

BACKGROUND: From November 2014 to November 2015, an experiment in French community pharmacies replaced traditional pre-packed boxes by per-unit dispensing of pills in the exact numbers prescribed, for 14 antibiotics. METHODS: A cluster randomised control trial was carried out in 100 pharmacies. 75 pharmacies counted out the medication by units (experimental group), the other 25 providing the treatment in the existing pharmaceutical company boxes (control group). Data on patients under the two arms were compared to assess the environmental, economic and health effects of this change in drug dispensing. In particular, adherence was measured indirectly by comparing the number of pills left at the end of the prescribed treatment. RESULTS: Out of the 1185 patients included during 3 sessions of 4 consecutive weeks each, 907 patients experimented the personalized delivery and 278 were assigned to the control group, consistent with a 1/3 randomization-rate at the pharmacy level. 80% of eligible patients approved of the per-unit dispensing of their treatment. The initial packaging of the drugs did not match with the prescription in 60% of cases and per-unit dispensing reduced by 10% the number of pills supplied. 13.1% of patients declared that they threw away pills residuals instead of recycling-no differences between groups. Finally, per-unit dispensing appeared to improve adherence to antibiotic treatment (marginal effect 0.21, IC 95, 0.14-0.28). CONCLUSIONS: Supplying antibiotics per unit is not only beneficial in terms of a reduced number of pills to reimburse or for the environment (less pills wasted and non-recycled), but also has a positive and unexpected impact on adherence to treatment, and thus on both individual and public health.

Quantifying population preferences around vaccination against severe but rare diseases: A conjoint analysis among French university students, 2016.

BACKGROUND: Several concepts are available to explain vaccine decision making by individual and inter-individual factors, including risk perception, social conformism and altruism. However, only a few studies have quantified the weight of these determinants in vaccine acceptance. Using a conjoint analysis tool, we aimed at eliciting preferences in a student population regarding vaccination against a rare, severe and rapidly evolving hypothetical disease, similar to meningococcal serogroup C meningitis or measles. METHODS: During March-May 2016, we conducted an emailing survey among university students aged 18-24years (N=775) in Rennes, France. Participants were asked to decide for or against immediate vaccination in 24 hypothetical scenarios, containing various levels of four attributes: epidemic situation, adverse events, information on vaccination coverage, and potential for indirect protection. Data were analysed using random effect estimator logit models. RESULTS: Participants accepted on average 52% of scenarios and all attributes significantly impacted vaccination acceptance. The highest positive effects were seen with an epidemic situation (OR 3.81, 95%-CI 3.46-4.19), 90% coverage in the community (3.64, 3.15-4.20) and potential for disease elimination from the community (2.87, 2.53-3.26). Information on "insufficient coverage" was dissuasive (vs. none of friends vaccinated: 0.65, 0.56-0.75). Controversy had a significantly greater negative effect than a confirmed risk of severe adverse events (OR 0.05 vs. 0.22). In models including participant characteristics, preference weights were unchanged, while trust in health authorities and vaccination perceptions strongly influenced acceptance themselves. The greatest significant variation of preference weights between subgroups was observed with controversy among students using alternative medicine daily (OR 0.28) and among students relying on scientific vaccine information (OR 0.02). CONCLUSIONS: Among young adults, potential for indirect protection and factual information on coverage in the community and potential side effects positively impact theoretical vaccine acceptance. Conjoint analyses should be conducted to understand vaccine hesitancy in specific vaccination programs.