Community policing does not build citizen trust in police or reduce crime in the Global South.

Is it possible to reduce crime without exacerbating adversarial relationships between police and citizens? Community policing is a celebrated reform with that aim, which is now adopted on six continents. However, the evidence base is limited, studying reform components in isolation in a limited set of countries, and remaining largely silent on citizen-police trust. We designed six field experiments with Global South police agencies to study locally designed models of community policing using coordinated measures of crime and the attitudes and behaviors of citizens and police. In a preregistered meta-analysis, we found that these interventions led to mixed implementation, largely failed to improve citizen-police relations, and did not reduce crime. Societies may need to implement structural changes first for incremental police reforms such as community policing to succeed.

COVID-19 vaccine acceptance and hesitancy in low- and middle-income countries.

Widespread acceptance of COVID-19 vaccines is crucial for achieving sufficient immunization coverage to end the global pandemic, yet few studies have investigated COVID-19 vaccination attitudes in lower-income countries, where large-scale vaccination is just beginning. We analyze COVID-19 vaccine acceptance across 15 survey samples covering 10 low- and middle-income countries (LMICs) in Asia, Africa and South America, Russia (an upper-middle-income country) and the United States, including a total of 44,260 individuals. We find considerably higher willingness to take a COVID-19 vaccine in our LMIC samples (mean 80.3%; median 78%; range 30.1 percentage points) compared with the United States (mean 64.6%) and Russia (mean 30.4%). Vaccine acceptance in LMICs is primarily explained by an interest in personal protection against COVID-19, while concern about side effects is the most common reason for hesitancy. Health workers are the most trusted sources of guidance about COVID-19 vaccines. Evidence from this sample of LMICs suggests that prioritizing vaccine distribution to the Global South should yield high returns in advancing global immunization coverage. Vaccination campaigns should focus on translating the high levels of stated acceptance into actual uptake. Messages highlighting vaccine efficacy and safety, delivered by healthcare workers, could be effective for addressing any remaining hesitancy in the analyzed LMICs.

Role of global longitudinal strain in assessment of left ventricular systolic function in patients with heart failure with preserved ejection fraction.

OBJECTIVES: To detect systolic dysfunction in heart failure with preserved ejection fraction (HFpEF) patients by using global longitudinal strain (GLS). METHODS: This study included 46 heart failure patients: 24 with heart failure with reduced ejection fraction (HFrEF) and 22 with heart failure with preserved ejection fraction (HFpEF), and 20 patients with similar risk factor but no symptoms or signs of heart failure, matched for age and sex, as controls. All patients were screened by echocardiography. The ejection fraction of left ventricle was measured using Simpson's method and the GLS of the left ventricle was measured by using two-dimensional speckle tracking. RESULTS: Left ventricular ejection fraction (LVEF) was 61.90 ±â€¯2.94% in the controls, 60.45 ±â€¯7.4% in the HFpEF group (p = 0.421), and 32.75 ±â€¯8.45% in the HFrEF group (p = 0.001). The value of left ventricle (LV) GLS (controls =  -19.74 ±â€¯1.12%, HFpEF =  -15.03 ±â€¯2.03%, HFrEF =  -10.72 ±â€¯1.99%, p = 0.0001) was significantly impaired in the HFpEF group despite normal LVEF. CONCLUSION: There is significant left ventricular systolic impairment detected by GLS despite preserved LVEF.