Global cross-cultural validation of a brief measure for identifying potential suicide risk in 42 countries.

OBJECTIVES: This study aimed to examine the psychometric properties of the P4 suicide screener in a multinational sample. The primary goal was to evaluate the reliability and validity of the scale and investigate its convergent validity by analyzing its correlation with depression, anxiety, and substance use. STUDY DESIGN: The study design is a cross-sectional self-report study conducted across 42 countries. METHODS: A cross-sectional, self-report study was conducted in 42 countries, with a total of 82,243 participants included in the final data set. RESULTS: The study provides an overview of suicide ideation rates across 42 countries and confirms the structural validity of the P4 screener. The findings indicated that sexual and gender minority individuals exhibited higher rates of suicidal ideation. The P4 screener showed adequate reliability, convergence, and discriminant validity, and a cutoff score of 1 is recommended to identify individuals at risk of suicidal behavior. CONCLUSIONS: The study supports the reliability and validity of the P4 suicide screener across 42 diverse countries, highlighting the importance of using a cross-cultural suicide risk assessment to standardize the identification of high-risk individuals and tailoring culturally sensitive suicide prevention strategies.

Soil carbon storage responses to expanding pinyon-juniper populations in southern Utah.

Over the past several decades, the expansion and thickening of woodlands in the western United States has caused a range of ecological changes. Woody expansion often leads to increases in soil organic matter (SOM) pools with implications for both biogeochemical cycling and ecological responses to management strategies aimed at restoration of rangeland ecosystems. Here we directly measure C and N stocks and use simple non-steady-state models to quantify the dynamics of soil C accumulation under and around trees of varied ages in southern Utah woodlands. In the two pinyon-juniper forests of Grand Staircase Escalante National Monument studied here, we found approximately 3 kg C/m2 and approximately 0.12 kg N/m2 larger C and N stocks in soils under pinyon canopies compared to interspace sites. These apparent increases in soil C and N stocks under woody plant species were dominated by elevated SOM in the surface 10 cm of soil, particularly within non-mineral-associated organic fractions. The most significant accumulation of C was in the >850 microm fraction, which had an estimated C residence time of <20 yr. Rates of carbon accumulation following pinyon-juniper expansion appear to be dominated by changes in this fast-cycling surface soil fraction. In contrast, we found that after separating >850 microm organic matter from the remaining light fraction (LF), C had residence times of approximately 400 yr and mineral-associated (MA) soil C had residence times of approximately 600 yr. As a result, we calculate that input rates to the LF and MA pools to be 10 +/- 1 and 0.68 +/- 0.15 g m(-2) yr(-1) (mean +/- SE), respectively. These findings suggest that one consequence of management activities aimed at the reduction of pinyon-juniper biomass may be a relatively rapid loss of soil C and N pools associated with the >850 microm fraction. The temporal dynamics of the <850 microm pools suggest that carbon and nitrogen continue to accumulate in these fractions, albeit at very slow rates, and suggest that multidecadal storage of C following tree recruitment is limited to relatively small, subsurface fractions of the total soil C pool.